Cooperative Institute for Research in Environmental Sciences at the University of Colorado Boulder

AT786 - Practicum on Human Impacts on Weather and Climate - Spring 2005

Course Spring 2005: AT786- Practicum on Human Impacts on Weather and Climate

2 Credits, Location: Room 212B, ACRC, 10:00 - 11:40 Tuesdays, Classes Begin 1/18/05

Required Text

Human Impacts on Weather and Climate by William R. Cotton and Roger A. Pielke Sr.

Hardcover - 296 pages, 1995 
Academic Press; ISBN: 0521499291

View Table of Contents at

View Course Proposal


Messages to the Class

Hi Class,

Welcome to AT786. Our class on Tuesday will be unusual as we will start with a seminar at 9 am (if you can make it). Christopher Davey is defending his Ph.D. and he raises questions about the robustness and completeness of the surface temperature record that is the basis for so much of current climate policy. We will briefly meet than at 10 am (which is our normal start time), but will need to adjourn shortly thereafter as I need to complete Christopher's Ph.D. exam. However, we will set the framework of the class. Please e-mail if you can normally meet for 2 hours (10-noon) on Tuesdays. On Jan 25th, I will discuss "overlooked issues" in the climate change debate. To prepare for that talk please read paper #R-124 (View pdf) Pielke, R.A., 1991: Overlooked scientific issues in assessing hypothesized greenhouse gas warming. Environ. Software, 6, 100-107 also available on my website at /pubs/. The framework of the class will include discussion of each issue as we read about it. In addition, I will provide recommendations for papers for you to read on your selected class project and presentation. This project and presentation will be the criteria for your grade for the class. The book that we will refer to will be handed out over the next several weeks. We will also refer to the new National Academy of Sciences report "Radiative Forcing of Climate Change: Expanding the Concept and Addressing Uncertainties" available to download free from their website ( If you obtain that report, please read the Executive Summary by January 25th. See you on Tuesday!

Roger A. Pielke Sr. 

Hi Class, in addition to R-124, Dr. Pielke has assigned a newer paper on Overlooked Issues, paper #R-225 available at

R-225 Pielke, R.A. Sr., 2002: Overlooked issues in the U.S. National Climate and IPCC assessments. Climatic Change, 52, 1-11. (View pdf)

Thanks, dallas

Hi All,

I look forward to our first full class on Tuesday. Please send me your suggested climate metric that you would like to investigate. We have one so far (tropical cyclone frequency changes). As we discussed the goal of each investigation is to challenge conventional summaries of the IPCC and other climate trend conclusions to assess how robust they are. These presentations will further confirm their conclusions or refute them, or something in between. See you Tuesday. I will present my view on the topics I have published on to set the framework. Please plan on dialog among us on the issues, and how to further examine them. Roger

Hi All, FYI (we will forward new work relevant to our class as we receive them this semester. See below.


Date: Wed, 19 Jan 2005 12:25:39 +0100
From: BENISTON Martin <>
To: BENISTON Martin <>



You may be interested in the attached paper that has just appeared in the American journal "Geophysical Research Letters". View pdf In this paper, I show that if the high temperatures recorded during heat waves (such as 2003 with 8-10°C above the average values) receive high media attention, some winters in the Alps exhibit temperatures exceeding 16°C above their mean values; in other words, these events are "heat waves" in the coldest part of the year! The trends of anomalously warm periods during alpine winters have increased in the course of the 20th century, and since the 1970s, winters are those which exhibit the highest temperature anomalies compared to the other seasons of the year. I have in addition attempted to show the role of the "North Atlantic Oscillation" on the behavior of these "warm winter spells"; the North Atlantic Oscillation is perceptible particularly in winter and can strongly influence climate on both sides of the Atlantic. These strong "warm winter spells" can lead to significant impacts, such as early snow melt, winter time floods, problems for the ski industry, an early start to the vegetation cycle of alpine plant species, and so on.


This paper was written in the context of the Swiss "NCCR-Climate" and EU "PRUDENCE" projects, and these projects have been acknowledged. I will be presenting this paper at the forthcoming EGU General Assembly Meeting in Vienna (April 24-29, 2005) in the Session CL12 dedicated to "Extreme Climate Events: Modeling, Observations and Impacts".


Best regards, Martin Beniston

Prof. Martin Beniston, Director, Geography Unit, Department of Geosciences, University of Fribourg, Chemin du Musee 4, CH-1700 Fribourg, Switzerland, Martin.Beniston@Unifr.CH,

Hi All- Tomorrow I will present the talk We also need you to select your project for the class (those who are taking the class for credit). So far we have: 

1. Jana Heisler- changes in precipitation frequency and amounts
2. Phil Klotzbach- changes in tropical cyclone frequency and intensity
3. Toshi Matsui - aerosol indirect effect - does the global average (W/m2) matter for climate?

4. Jacob Jawson - regional land-use change, specifically Germany

Topics that would be really interesting to look at are
i) Arctic/Antarctic sea ice trends
ii) Northern Hemispheric snow cover trends
iii) green-out in the spring (NH and/SH) trends
iv) ocean heat content trends
v) surface land temperature trends
vi) tropospheric temperature trends
vii) tropospheric water vapor content trends
viii) surface enthalpy changes
others? Roger


For next Tuesday's class, I would like us to discuss the existing papers on the following subjects listed below under topics.
What I would like you to do is to search for papers on these subjects listed below (under each heading) and send to each member on our list above (as soon as possible, so that we have time to read them). This includes information from the most recent IPCC report. These papers will form the basis of our discussions. Start with topic #1; we will spend as much time on each subject as needed. For starting papers, I have listed several of my papers. However, you should find work by other authors in order to provide balance.

The week following we will go over the new NRC report (I expect to have copies to hand out to you on Tuesday).

In following weeks, we will go over the published work on other metrics; please let me know ones you have a specific interest in.

On the book that is listed on the web site (Human Impacts on Weather and Climate), I plan to provide you a copy by the third or fourth week of February, and will assign readings from there at that time. Roger P.


Subject: John Walsh interview

Hi All, Here is an interesting e-mail by one of the experts on Arctic sea ice.


Hi Class, Please add the following papers to the list we will discuss tomorrow:

1. Ellis, J. S. and T.H. VonderHaar, 1978: The annual variation in the global heat balance of the Earth. JGR. 83. No. C4. 1958-1962. Copies will be handed out.

2. Omstedt, A. and C. Nohr, 2004: Calculating the water and heat balances of the Baltic Sea using ocean modeling and available meterological, hydroliogical and ocean data. Tellus. 56A, 400-414. PDF

3. Beltrami, H. et al. 2000: Energy balance at the Earth's surface: heat flux history in eastern Canada. GRL, 27, 3385-3388. PDF

4. Beltrami, H., 2002: Climate from borehole data: energy fluxes and temperatures since 1500. GRL. 29, doi:10.1029/2002GL015702,2002. PDF

5. Beltrami, H. et al. 2002: Continental heat gain in the global climate system. GRL, 29, doi:10.1029/2002GL014310,2002. PDF

Also, look at the ocean monitoring data reported in

and associated links. Also, send to all of us any links you have found to look at this metric.

Please come to class ready to discuss the pros and cons of using heat as the climate metric, as well as what the data says of trends. Roger P.

See also the news stories

Hi All, Anyone want to address this issue? As we showed today, the SSTs over much of the Southern oceans appear to be cooler than the long term average, so how do the statements in this news release match with reality? Roger P.

Subject: Antarctic ice collapse

Hi Class, This paper on the rapid changes in landscape will be of interest in our discussion of its role on surface temperature trends.

Lepers, E., E.F. Lambin, A.C. Janetos, R. DeFries, F. Achard, N. Ramankutty, and R.J. Scholes, 2005: A synthesis of information on rapid land-cover change for the period 1981-2000. BioScience, 55, 115-124. PDF

Roger P.


Hi Class, You might find this collection of papers useful as resources for the range of perspectives of views on climate change. The author of the web site that is posting these papers has a defined (skeptical) view of the climate change debate, but he is inclusive in listing papers and views. The ones on data are relavant for our class. Roger P.

Hi Class, I am summarizing below my interpretation the the ocean heat budget data. I invite you to also submit a summary, if you chose. Dallas will post on our web site.

Ocean Heat Storage Changes

1. On the order of 90% of the multi-decadal radiative imbalance of the climate system is stored in the ocean.

2. The global average ocean heat storage has warmed over the last 50 years at a rate in the upper 750m that is about 0.6 Watts per meter squared over the period 1993-2003, when globally averaged. This rate of heating also occurred in the early 1970s.

3. The heating is dominated by ocean temperature increases spread uniformly through the water column (750m) centered on 40 degrees South latitude.

4. This spatial distribution of ocean heating needs to be accurately simulated in order to have confidence in climate simulation models, with respect to whether they can skillfully simulate climate change due to a radiative imbalance.

I plan to write similar brief summaries for our other metrics. We should discuss tomorrow, if you disagree with any of the conclusions listed above.

Roger P.

Hi, Roger and class,

With respect to its dominant heat content, I think we need the 3000m depth of heating content, as long as data available.

In comparison between Figure 1 and Figure 4 in Levitus et al. 2000, 750m-depth heating is quite fluctuated. This is like a situation that make a drought index with the deep soil moisture in stead of shallow soil moisture.

So, in my opinion, we need not only spatial but also vertical profile of heating to evaluate the model skill. I also think the ocean heat profile could be linked to abrupt change in global weather pattern.

Indeed, none of the current ocean model can reproduce the observed multi-year variability in ocean heat content, e.g., Figure 1 in Levitus et al. [2001], which showed just the smooth trend of heat content. Toshi

Thanks Toshi- The reason, as I understand, that they did not go deeper into the ocean in the Willis et al study was that the data at those levels were too sparse. However, you are correct that deeper information is needed. More comments from class? Roger

Hi Class, Yesterday's class was very informative with good discussion. My summary of the three metrics are:

1. Antarctic sea ice - there is no multidecadal trend (over the last several decades), but considerable interannual variations of the maximum areal coverage occur. Most of the sea ice disappears each summer.

2. Northern Hemisphere snow cover- The maximum extent and total area covered during the year shows no significant trend over the last decade or so. There has been an earlier spring melt-off, but there is no trend in the fall coverage.

3. Arctic sea ice- The area covered has decreased over the last decade but at a rate that is significantly slower than given in the ACIS study. The multi-year ice coverage shows no significant trend over recent years, although this data is harder to come by in real time. The current winter coverage (Feb 2005) is the lowest in the period of record. However, as recently as December, 2004, the anomaly was close to its long term (1979-2000) average. Arctic sea ice concentrations and areal coverage are particularly important climate change metrics to follow, as they are monitored effectively by satellites.

Please add your conclusions (under your name, as you would like). Roger P.

Hi All, This url (by my son) on cherrypicking might be of interest to you, and is relevant to our class.

Roger P. Sr.

Subject: Re: CIRA SEMINAR: Dr. Z. Johnny Luo, Tuesday, February 15, 10:00 AM. CIRA South Conference Room 

Hi All, I did not note the time of the seminar, however, it seems to fit with our class, so please attend it. We will convene immediately thereafter and start on tropospheric temperatures. Roger P.

Two new papers for your overview from Roger:

Raddatz, R.L., 2005: Moisture recycling on the Canadian Prairies for summer droughts and pluvials from 1997-2003. Agric. Forest Meteor., Special Issue, submitted. PDF 

Raddatz, R.L., 2005: Evidence for the influence of agriculture on weather and climate through the transformation and management of vegetation: Illustrated by examples from the Canadian Prairies. Agric. Forest Meteor., Special Issue, submitted. PDF

Hi All, Please remember to send me citations and urls of data of tropospheric temperature trends before class on Tuesday. We will start our discussion of this right after the seminar. Roger P.

Hi Class, Khishig has forwarded the link below for tropospheric temperature data (and there is other useful information on this site).

Roger P.

Some news story on this year and last year warmth.

2004 Was Fourth-Warmest Year Ever Recorded:

NASA: 2005 could be warmest year recorded:


Hi, class, I realized that some of you (non-atmos or non-radiation background) do not have much of an idea about how space-borne remote sensing can estimate the atmospheric/surface variables.

I have attached ECMWF's introductory courses.

Eyre, J.R., 2002: Inversion methods for satellite sounding data; April 1991. Meteorological Training Course Lecture Series, ECMWF. PDF

Rizzi, R., 2002: Principles of remote sensing of atmospheric parameters from space; February 1998. with updates by Saunders. Meteorological Training Course Lecture Series, ECMWF. PDF

Since our course reads alot of papers using remote sensing techniques, you can take a look, or brush up on your knowledge. Toshi

Hi Class, This web site was sent to me on a history of climate modeling (with one perspective). It will also make for a good discussion among us!

Please send us any web sites you find. Roger P.


Hi everyone. Here's an article discussing the Kyoto Protocol, which goes into effect today. The article is from CNN's webpage: Phil

Hi Class, To provide a background on tropospheric temperature measurements, Dallas is placing a report by Scott Church on our web site. It is a long discussion, but does provide an overview of satellite and radiosonde measurement techniques (and his interpretation of the results), which I can forward to you. There are numerous figures and we will discuss some of these on Tuesday. I am not assigning specific pages to read, but prefer you select those parts you are most interested in and be prepared to discuss with us in class (since it is quite a task to read all of the report!). The report provides different perspective on the issue of tropospheric (and surface) temperature trends. Roger P.

Church, Scott, 2005: Climate Change & Tropospheric Temperature Trends: Part I - What do we know today and where is it taking us? PDF 

Church, Scott, 2005: Climate Change & Tropospheric Temperature Trends: Part II - A Critical Examination of Skeptic Claims. PDF

Hi Class, We will be discussing the "hockystick" controversy later. This Science overview is useful to help frame the debate. Roger P. PDF 

Hi AT 786- We will discus Tuesday as to whether the ocean heat content results we discussed in class support the conclusions made in the news releases below.

Here is the actual press release.


Roger P.

Subject: And more news articles on the AAAS Press release (Harvard study)

Subject: and another new interview on the ocean heat budget claim (fwd)

Hi AT 786, Here is another paper, with some new quotes.

Roger P.

Hi AT 786 I am sharing with you the e-mail I have sent to the authors of the one study. I will also let you know what I learn back from them. Roger P.


---------- Forwarded message ----------
Date: Sat, 19 Feb 2005 16:45:24 -0700
From: "Roger A. Pielke, Sr." <>
Subject: News Article

Hi Loretta and Daniel, I read the news release given below

I wanted to alert you a research paper that we have published that raises doubt as to whether a significant change in the north-south tropospheric temperature gradient (as represented by the 200 mb winds through the thermal wind relation) has changed (at least through the periods of our studies). This paper is:

Pielke, R.A. Sr., T.N. Chase, T.G.F. Kittel, J. Knaff, and J. Eastman, 2001: Analysis of 200 mbar zonal wind for the period 1958-1997. J. Geophys. Res., 106, D21, 27287-27290.

We also have published work on whether there has been a trend in the area of the coldest temperatures at 500 mb in the Northern Hemisphere (this temperature is an effective metric of thermal gradients that can develop in the winter, as the 500 mb temperatures in the tropics are relatively invariant). We did not find a trend, and present evidence for an important feedback in the real climate system, that does not appear to be treated properly in current GCMs.

This research is reported in

Chase, T.N., B. Herman, R.A. Pielke Sr., X. Zeng, and M. Leuthold, 2002: A proposed mechanism for the regulation of minimum midtropospheric temperatures in the Arctic. J. Geophys. Res., 107(D14), 10.10291/2001JD001425.

Tsukernik, M., T.N. Chase, M.C. Serreze, R.G. Barry, R. Pielke Sr., B. Herman, and X. Zeng, 2004: On the regulation of minimum mid-tropospheric temperatures in the Arctic. Geophys. Res. Letts., 31, L06112, doi:10.1029/2003GL018831.

Also, while I assume you have used a newer version of the GISS model, we found that an earlier version could not replicate even the global averaged tropospheric temperature gradient.

Chase, T.N., R.A. Pielke Sr., B. Herman, and X. Zeng, 2004: Likelihood of rapidly increasing surface temperatures unaccompanied by strong warming in the free troposphere. Climate Res., 25, 185-190.

Since the current version of the model (I presume even today) does not have all of the first order climate forcings (as we concluded on Daniel's NRC Committee), their predictive results should be viewed with caution (however, I would like to see the specific study to learn more on it; please send).

With Best Regards, Roger

Roger A. Pielke Sr. Professor 970-491-8293

Subject: Re: Oceans - discernible human influence? (fwd)

Hi Class, I am receiving a large number of e-mails on this issue. I am forwarding you this particular one since it is the view of the New Yor Times and thus will have wide dissemination. I suggest you suscribe to these lists if you want to stay current with the internet debate.

Roger P.


---------- Forwarded message ----------
Date: Sun, 20 Feb 2005 10:08:47 -0500

Wanted to offer an observation about Tim Barnett at Scripps, who's come out with the new findings on human fingerprint in ocean heat buildup. Just five years ago, he counted himself among those arguing it was not possible to discern a signal of human influence. To my mind, that gives his statements now some significant weight.

Here's what Bill Stevens wrote in NYT back in 2000

February 29, 2000, Tuesday Late Edition - Final
Global Warming: The Contrarian View

Over the years, skeptics have tried to cast doubt on the idea of global warming by noting that measurements taken by earth satellites since 1979 have found little or no temperature rise in large parts of the upper atmosphere. The satellites' all-encompassing coverage yields more reliable results than temperature samplings showing a century-long warming trend at the earth's surface, they argued.

In January, a special study by the National Research Council, the research arm of the National Academy of Sciences, declared that the ''apparent disparity'' between the two sets of measurements over the 20-year history of the satellite measurements ''in no way invalidates the conclusion that surface temperature has been rising.'' The surface warming ''is undoubtedly real,'' the study panel said.

But the dissenters are a long way from conceding the debate, and they have seized on other aspects of the panel's report in an effort to bolster their case.

To be sure, according to interviews with some prominent skeptics, there is now wide agreement among them that the average surface temperature of the earth has indeed risen.

''I don't think we're arguing over whether there's any global warming,'' said Dr. William M. Gray, an atmospheric scientist at Colorado State University, known for his annual predictions of Atlantic hurricane activities as well as his staunch, longtime dissent on global climate change. ''The question is, 'What is the cause of it?' ''

On that issue, and on the remaining big question of how the climate might change in the future, skeptics continue to differ sharply with the dominant view among climate experts.

The dominant view is that the surface warming is at least partly attributable to emissions of heat-trapping waste industrial gases like carbon dioxide, a product of the burning of fossil fuels like coal, oil and natural gas. A United Nations scientific panel has predicted that unless these greenhouse gas emissions are reduced, the earth's average surface
temperature will rise by some 2 to 6 degrees Fahrenheit over the next century, with a best estimate of about 3.5 degrees, compared with a rise of 5 to 9 degrees since the depths of the last ice age 18,000 to 20,000 years ago. This warming, the panel said, would touch off widespread disruptions in climate and weather and cause the global sea level to rise and flood many places.

Dr. Gray and others challenge all of this. To them, the observed surface warming of about 1 degree over the last century -- with an especially sharp rise in the last quarter century -- is mostly or wholly natural, and there is no significant human influence on global climate. They also adhere firmly to their long-held opinion that any future warming will be inconsequential or modest at most, and that its effects will largely be beneficial.

In some ways, though, adversaries in the debate are not so far apart. For instance, some dissenters say that future warming caused by greenhouse gases will be near the low end of the range predicted by the United Nations scientific panel. And most adherents of the dominant view readily acknowledge that the size of the human contribution to global warming is not yet known.

The thrust-and-parry of the climate debate goes on nevertheless.

With the National Research Council panel's conclusion that the surface warming is real, ''one of the key arguments of the contrarians has evaporated,'' said Dr. Michael Oppenheimer, an atmospheric scientist with Environmental Defense, formerly the Environmental Defense Fund.

But those on the other side of the argument see things differently.

To them, the most important finding of the panel is its validation of satellite readings showing less warming, and maybe none, in parts of the upper atmosphere, said Dr. S. Fred Singer, an independent atmospheric scientist who is an outspoken dissenter.

For him and other climate dissenters, this disparity is key, in that it does not show up in computer models scientists use to predict future trends. The fact that these models apparently missed the difference in warming between the surface and the upper air, the skeptics say, casts doubt on their reliability over all.

Experts on all sides of the debate acknowledge that the climate models are imperfect, and even proponents of their use say their results should be interpreted cautiously.

A further problem is raised by the divergent temperatures at the surface and the upper air, said Dr. Richard S. Lindzen, an atmospheric scientist at the Massachusetts Institute of Technology, who is a foremost skeptic. ''Both are right,'' But, he said, increasing levels of greenhouse gases should warm the entire troposphere (the lower 6 to 10 miles of the atmosphere). That they have not, he said, suggests that ''what's happening at the surface is not related to the greenhouse effect.''

Skeptics also argue that the lower temperatures measured by the satellites are confirmed by instruments borne aloft by weather balloons. But over a longer period, going back 40 years, there is no discrepancy between surface readings and those obtained by the balloons, said Dr. John Michael Wallace, an atmospheric scientist at the University of Washington in Seattle, who was chairman of the research council study panel.

Although the climate debate has usually been portrayed as a polarized argument between believers and contrarians, there is actually a broad spectrum of views among scientists. And while the views of skeptics display some common themes, there are many degrees of dissent, many permutations and combinations of individual opinion. The views of some have changed materially over the years, while others have expressed essentially the same basic opinions all along.

One whose views have evolved is Dr. Wallace, who describes himself as ''more skeptical than most people'' but ''fairly open to arguments on both sides'' of the debate. He says the especially sharp surface warming trend of the 1990's has ''pulled me in a mainstream direction.'' While he once believed the warming observed in recent decades was just natural variation in climate, he said, he is now perhaps 80 percent sure that it has been induced by human activity -- ''but that's still a long way from being willing to stake my reputation on it.''

A decade ago, Dr. Wallace said, many skeptics questioned whether there even was a surface warming trend, in part because what now appears to be a century-long trend had been interrupted in the 1950's, 1960's and early 1970's, and it had not yet resumed all that markedly. But the surge in the 1980's and 1990's changed the picture substantially.

Today, Dr. Wallace said, few appear to doubt that the earth's surface has warmed. One prominent dissenter on the greenhouse question, Dr. Robert Balling, a climatologist at Arizona State University, says, ''the surface temperatures appear to be rising, no doubt,'' and other skeptics agree.

There also appears to be general agreement that atmospheric concentrations of greenhouse gases are rising. At 360 parts per million, up from 315 parts in the late 1950's, the concentration of carbon dioxide is nearly 30 percent higher than before the Industrial Revolution, and the highest in the last 420,000 years.

Mainstream scientists, citing recent studies, suggest that the relatively rapid warming of the last 25 years cannot be explained without the greenhouse effect. Over that period, according federal scientists, the average surface temperature rose at a rate equivalent to about 3.5 degrees per century -- substantially more than the rise for the last century as a whole, and about what is predicted by computer models for the 21st century.

But many skeptics, including Dr. Gray and Dr. Singer, maintain that the warming of the past 25 years can be explained by natural causes, most likely changes in the circulation of heat-bearing ocean waters. In fact, Dr. Gray says he expects that over the next few decades, the warming will end and there will be a resumption of the cooling of the 1950's and 1960's.

At bottom, people on all sides of the debate agree, the question of the warming's cause has not yet been definitively answered. In December, a group of 11 experts on the question looked at the status of the continuing quest to detect the greenhouse signal amid the ''noise'' of the climate's natural variability.

The lead author of the study was Dr. Tim P. Barnett, a climatologist at the Scripps Institution of Oceanography in La Jolla, Calif. Dr. Barnett, who has long worked on detecting the greenhouse signal, describes himself as a ''hard-nosed'' skeptic on that particular issue, even though he believes that global warming in the long run will be a serious problem.

The study by Dr. Barnett and others, published in The Bulletin of the American Meteorological Society, concluded that the ''most probable cause'' of the observed warming had been a combination of natural and human-made factors. But they said scientists had not yet been able to separate the greenhouse signal from the natural climate fluctuations. This state of affairs, they wrote, ''is not satisfactory.''

Two big questions complicate efforts to predict the course of the earth's climate over the next century: how sensitive is the climate system, inherently, to the warming effect of greenhouse gases? And how much will atmospheric levels of the gases rise over coming decades?

The mainstream view, based on computerized simulations of the climate system, is that a doubling of greenhouse gas concentrations would produce a warming of about 3 to 8 degrees. But Dr. Lindzen and Dr. Gray, pointing to what they consider the models' problems with the physics of the atmosphere, say they overestimate possible warming. It ''will be extremely little,'' Dr. Gray said. How little? Dr. Lindzen pegs it at about half a degree to a bit less than 2 degrees, if atmospheric carbon dioxide doubles.

Other factors in the climate system modify the response to heat-trapping gases, and the United Nations panel's analysis included these to arrive at its projection of a 2- to 6-degree rise in the average global surface temperature by 2100. One factor is various possible levels of future carbon dioxide emissions. Dr. Singer, saying that improving energy efficiency will have a big impact on emissions, predicts a warming of less than 1 degree by 2100.

Dr. Balling projects a warming just shy of 1 degree for the next 50 years, not out of line with the United Nations panel's lower boundary. Another skeptic, Dr. Patrick J. Michaels, a climatologist at the University of Virginia, similarly forecasts a greenhouse warming rise of 2.3 degrees over the next century. As is now the case, he says, the warming would be most pronounced in the winter, at night, and in sub-Arctic regions like Siberia and Alaska. A warming of that magnitude, he and others insist, could not be very harmful, and would in fact confer benefits like longer growing seasons and faster plant growth.

''It should be pretty clear,'' he said, that the warming so far ''didn't demonstrably dent health and welfare very much,'' and he said he saw no reason ''to expect a sudden turnaround in the same over the next 50 years.'' After that, he said, it is impossible to predict the shape of the world's energy system and, therefore, greenhouse gas emissions.

A warming in the low end of the range predicted by the United Nations panel may well materialize, said Dr. Oppenheimer, the environmentalist. But, he said, the high end may also materialize, in which case, mainstream scientists say, there would be serious, even catastrophic, consequences for human society. ''There is no compelling evidence to allow us to choose between the low end, or the high end, or the middle,'' Dr. Oppenheimer said.

If business continues as usual, the world is likely at some point to find out who is right.

Andrew C. Revkin, Environment Reporter, The New York Times
229 West 43d St. NY, NY 10036
Tel: 212-556-7326, Fax: 509-357-0965 (via, received as email)
Recent Arctic coverage:
Book on the Amazon, The Burning Season ( )

Subject: ocean heat budget and the new Barnett et al study (fwd)

Hi Class, FYI; we will discuss tomorrow. Please send out any information you have on this subject also. Roger


---------- Forwarded message ----------
Date: Mon, 21 Feb 2005 15:11:33 +0000
Subject: ocean heat budget and the new Barnett et al study

Hi Timo

Please send out to the mailing group regarding the Barnett et al study.
I am quite familiar with the earlier ocean heat budget study of Tim Barnett and, in fact, agree with him that the ocean is the component of the climate system where most of a radiative imbalance accumulates as Joules. I discussed this in Pielke Sr., R.A., 2003: Heat storage within the Earth system. Bull. Amer. Meteor. Soc., 84, 331-335. However, I have not seen his new research.

The new work that I have seen (Willis, J.K., D. Roemmich, and B. Cornuelle, 2004: Interannual variability in upper ocean heat content, temperature, and thermosteric expansion on global scales. J. Geophys. Res., 109, C12036, doi: 10.1029/2003JC002260. presents a challenge to the models that must be met as a necesary condition of any new modeling results to be accepted as skillful. As stated in the Willis et al paper

"Maps of yearly heat content anomaly show patterns of warming commensurate with ENSO variability in the tropics, but also show that a large part of the trend in global, oceanic heat content is caused by regional warming at midlatitudes in the Southern Hemisphere."

This heating

"...centered on 40S is spread more uniformly over the water column and warms steadily throughout the entire time series..."

This is for the period mid-1993 through mid-2003.

They further find that, with respect to the current rate of warming (as compared with the Levitus et al earlier data)

"....the warming rate in the early 1970s is comparable to the present rate.....With the present time series, it is therefore not possible to identify whether the recent increase in ocean warming is due to an acceleration of heat uptake by the ocean or is simply decadal variability".

These results rasise the following quesions:

1. Does the model replicate this concentration of heat in the southern latitude ocean?

2. Since a substantial portion of the recent heating is well below the surface, how did it get there?

3. Does this transfer of heat to below the sea surface (if this is what occurs) indicate a mechanism for the climate system to "sequester heat" in response to a radiative imbalance in the atmosphere?

3. What does the removal of this heat from direct contact with the atmopshere (i.e. through SSTs) indicate for tropospheric heating?

These are important science questions that the new Barnett et al study must address.


Subject: Re: Oceans - discernible human influence? (fwd)

Hi Class

Not to overwhlem you with papers, but here is another one. Roger P.

Hoffert, M.I., A.J. Callegari, and C.-T. Hsieh, 1980: The role of deep sea heat storage in the secular response to climatic forcing. J. Geophys. Res., 85, 6667-6679. PDF

Subject: re: Hockey Stick (fwd)

Hi AT 786, Here is another web site with comments on the hockey stick (which, as I mentioned we will discuss in a few weeks). Roger P.

Subject: MSNBC news release

Hi Class, Is is another one to discuss. I have not yet had a reply from the Harvard group. Roger P.

Subject: FYI: Scientists Advance In Detection And Attribution Of Climate Change

Hi Class, More..... Roger P.


---------- Forwarded message ----------
Date: Tue, 22 Feb 2005 07:52:31 -0600
From: Michael Schlesinger <>
To:, 'Douglas Hoyt' <>,
Scientists Advance In Detection And Attribution Of Climate Change
Date 2005/2/22 11:22:07 | Topic: Science and Energy News

Scientists Advance In Detection And Attribution Of Climate Change
WASHINGTON, D.C. - Access to the next generation of climate change experiments has helped scientists obtain more comprehensive estimates of the expected "signal" of human influences on climate.

Improved knowledge of this signal, and a better understanding of uncertainties in temperature observations, have helped to advance "detection and attribution" ("D&A") studies, which assist in unraveling the causes of recent climate change.

"The climate system is telling us an internally consistent story," said Ben Santer, an atmospheric scientist at Lawrence Livermore National Laboratory. "We've observed warming of the Earth's land surface and oceans, cooling of the stratosphere, an increase in height of the tropopause, retreat of Arctic sea ice, and widespread melting of glaciers. These changes are difficult to reconcile with purely natural causes."

Santer reports today on the identification of human influences on recent atmospheric temperature changes during a climate change session at the American Association for the Advancement of Science annual meeting in Washington, D.C. The title of the panel is "Detection and Attribution - Methods and Results - of Climate Trends in Temperature Sensors, Species and Glaciers."

Santer works in Livermore's Program for Climate Model Diagnosis and Intercomparison (PCMDI), and has compared new computer model simulations performed at several different research institutes to observational records of recent temperature change.

The climate models analyzed by Santer and colleagues included changes in both manmade forcings (well-mixed greenhouse gases, tropospheric and stratospheric ozone, and the scattering effects of sulfate aerosols) and natural external forcings (solar irradiance and volcanic aerosols).

Earlier Livermore research has determined that human-induced changes in ozone and well-mixed greenhouse gases are the primary drivers of recent changes in the height of the tropopause - the boundary between the turbulently mixed troposphere and the more stable stratosphere. Research with new model and observational datasets strengthens these findings.

"With new model experiments coming online, we're now in a much better position to estimate how climate changed in response to combined human and natural influences," Santer said.

PCMDI is archiving data from recently completed experiments performed with coupled ocean-atmosphere general circulation models that took place at more than a dozen research institutes worldwide. "This data will be a very valuable resource for the Laboratory and the whole community," Santer said. "We are sitting on a real scientific goldmine."

Founded in 1952, Lawrence Livermore National Laboratory has a mission to ensure national security and to apply science and technology to the important issues of our time. Lawrence Livermore National Laboratory is managed by the University of California for the U.S. Department of Energy's National Nuclear Security Administration.

This article comes from .: All American Patriots :

Subject: FYI: Maine moving to cool down climate change

Tuesday, February 22, 2005

Maine moving to cool down climate change

By JOHN RICHARDSON, Portland Press Herald Writer

Copyright © 2005 Blethen Maine Newspapers Inc.

The United States watched from the sidelines last week as 141 other countries began a global effort to reduce air pollution that may be heating up the planet.

But that doesn't mean Mainers won't be asked to do their part.

Maine lawmakers are considering a slew of proposals coming out of a state plan to reduce Maine's so-called greenhouse-gas pollution.

A first round of potential changes for Maine includes the sale of more fuel-efficient cars and energy-efficient appliances, requirements for more energy efficient construction and the use of more renewable power sources that don't pollute the air.

Maine is one of a growing number of states adopting policies and passing laws intended to slow climate change in the absence of federal action.

"The states are doing what they've always done, which is they take matters into their own hands," said Michael Stoddard of Environment Northeast, a
Portland-based advocacy group.

The Kyoto Protocol took effect Wednesday. The international agreement says participating countries must reduce emissions of carbon dioxide and other air pollutants to 5 percent less than 1990 levels by 2012.

It takes effect as scientists point to growing evidence of global warming, which they say is caused by carbon dioxide and other pollutants building up in the atmosphere. Carbon dioxide from power-plant smokestacks and car tailpipes can act as a blanket, or a greenhouse window, trapping heat, scientists say.

The Bush administration has refused to participate in the global agreement, saying it would cause too much harm to the nation's economy and does not include other key countries, particularly China and India. President Bush said last week that he believes the answer lies in new technology - such as a federally funded effort to build a clean coal-burning plant.

State agencies and legislatures, meanwhile, are starting to take action. Led by efforts in the Northeast and on the West Coast, more than half of the states now have formal action plans for fighting climate change.


Since 2001, Maine has been working with other Northeastern states toward regional pollution controls. The states are still working toward a Kyoto-like plan to cap emissions and allow power plants and other polluters to trade pollution credits, a system that creates a financial incentive to clean up. Details of the plan could be presented this spring.

Maine's Legislature has already committed to reducing greenhouse-gas emissions to 1990 levels by 2010, and 10 percent below that by 2020. The goal led to the release of a state action plan in December and the introduction of more than a dozen related bills this year.

Proposals include measures to fight sprawling development, a trend that leads to more automobile travel and pollution, and to promote forestry practices to maintain trees, which take carbon dioxide out of the atmosphere. Most proposals would increase energy efficiency and, as a result, reduce carbon-dioxide pollution.

"If we don't act in the next decade or two, it'll go to the point where we have put it out of our control," said state Rep. Ted Koffman, D-Bar Harbor, sponsor of a 2003 law that led to Maine's action plan. "We can make some difference and we have an obligation as citizens of the country to do our part."


While Maine is a relatively small contributor of carbon dioxide, advocates say the state has a lot at stake and may already be feeling the effects of rising global temperatures.

Coastal communities dealing with beach erosion could face rising sea levels, which accelerate the process and magnify the damage caused by storms, according to scientists. Fishermen and farmers could struggle with shifting seasons and new diseases. Rising temperatures are also seen as a threat to Maine's winter tourism industries such as skiing and snowmobiling, and the maple-syrup industry.

"These are very important industries to the state of Maine, economically and culturally," said Sue Jones of the Natural Resources Council of Maine. "In order to solve the problem of global warming, everyone has to do their share."

State Rep. Henry Joy, R-Crystal, said he thinks the state is making a mistake by trying to take on global warming, citing conflicting scientific research. Those warning about dramatic climate change are ignoring scientists who say rising temperatures are modest and not primarily caused by pollution, he said.

"That's fine if they want to do this with an idea of conserving energy, but they're not looking at the other side of it and what the costs would be for the regulated community," Joy said. "It's scare tactics to move forward an agenda."

Joy has introduced a climate-change bill of his own. His bill, which will be the subject of a public hearing in Augusta today, says that before adopting rules related to global warming, the state would have to determine the amount of global warming that would be prevented and the costs of the rules. That, Joy said, would show that the costs are not worth it.

Some of the individual proposals also face targeted opposition.


One prominent proposal would require that, by 2009, 10 percent of vehicles sold by Maine auto dealers be clean, efficient cars such as gas-electric hybrids or some new-generation gasoline cars. Maine's Board of Environmental Protection approved the rule last fall and Maine's Legislature is expected to make a final decision as soon as next month.

"Consumers in Maine can't get hybrids right now," Jones said.

Despite increases in production, dealerships such as Prime Toyota in Saco have about a six-month waiting list for people who want to buy the Toyota Prius, a gas-electric hybrid that gets more than 40 miles to the gallon and has a base price of about $21,400. The rule would also require the sale of more efficient gasoline cars.

Auto manufacturers and dealers hope to defeat the plan, or at least change it to provide more flexibility.

Because some cars would be given only partial credit, the rule would actually mean that 25 percent or more of Maine cars would be in the category of low emission vehicles, they say. And Mainers, who overwhelmingly prefer light trucks, aren't going to buy the more efficient vehicles, they say. That could leave unsold compact cars filling dealership lots and prevent deliveries of larger cars and trucks, said Tom Brown, director of the Maine Auto Dealers Association.

"If it passed, the manufacturers have said they would have to limit the availability of (other) product to Maine so they could meet the standards," Brown said.

Car makers also argue that new cars are already far cleaner than most cars on the road.

"There's no real air-quality benefit of this (proposal) any more," said Greg Dana of the Alliance of Auto Manufacturers, a national industry group based in Washington, D.C.

Thomas McInerney, a physician in Cape Elizabeth, said he thinks plenty of Mainers would buy more efficient cars because they want to make a difference, even a small one.

He bought a Prius last fall partly because of what he heard and read about climate change.

"Global warming is really a fossil-fuel issue. If you burn less, you contribute less. If you burn more, you contribute more," he said. "I think what I can do about it is just make any smart choices, as small as they are. It has to start somewhere."

Staff Writer John Richardson can be contacted at 791 - 6324 or at:

TO CLEAR THE AIR HERE ARE SOME of the proposals facing Maine's Legislature aimed in part at fighting pollution linked to global warming and climate change. Some proposals have not yet been presented in detail.

- A RESOLUTION to require that, by 2009, cleaner and more fuel-efficient cars represent at least 10 percent of the vehicles sold by Maine auto dealers. The cars would include gas-electric hybrids and certain gasoline-powered cars. The actual percentage could be higher because not all cars get full credit.

- A BILL TO REQUIRE that 18 common appliances, including torchiere lamps and exit signs, meet minimum energy efficiency standards.

- A BILL TO INCREASE the amount of renewable energy sources that supply power in Maine, thereby cutting power plant air pollution. The state now requires that 30 percent come from renewable sources.

- BILLS TO REQUIRE more energy efficiency standards in building codes.

- Bills to discourage sprawl-type development that leads to more energy use and a constant increase in the miles driven - and gasoline burned - by Maine residents.

- RESOLUTIONS TO ENCOURAGE forestry practices that conserve trees, which take carbon dioxide out of the atmosphere.

Subject: Prometheus

Please add this url to the ones you look at. It is updated each day during the workweek. It provides a science policy perspective to the use of dataand science for political reasons, among other issues.

Roger P.


Subject: FYI: Hot summer a sign of warming planet PREVIEW: Record heat reveals what rest of world will see in next 25 years

Hot summer a sign of warming planet
PREVIEW: Record heat reveals what rest of world will see in next 25 years.

By DOUG O'HARRA Anchorage Daily News

(Published: February 22, 2005)

For proof of climate change in the Arctic, look no further than Alaska's long, hot summer, according to one of the country's top climate scientists.

Last year Alaskans sweated through the warmest May, June, July and August of the century, with average temperatures almost 5 degrees Fahrenheit above normal. Such heat was largely driven by the warmest ocean temperatures ever measured in the Northern Hemisphere, matched globally by the fourth-warmest year on record.

Large swaths of the state saw sparse rainfall as a result but still got zapped thousands of times by lightning. That led to Alaska's worst fire season ever, with an estimated 6.5 million acres burned.

Throw in melting glaciers, disintegrating permafrost, diminishing sea ice, coastal erosion, changes in vegetation and wildlife, insect infestations, rising sea level, and increasing exposure to contaminants brought on air and sea currents, and Alaskans know firsthand about the potential damage and cost caused by the shifting climate.

"Climate is really warming now, and you Alaskans know that," said Robert Corell, chair of the Arctic Climate Impact Assessment for the international Arctic Council. "Because this really is the bellwether, the canary in the mine: What we see over the next decade here and in the Arctic, the rest of the world will see in the next 25 years."

Corell, a senior fellow with the American Meteorological Society, brought his climate-change message to Anchorage earlier this month, giving speeches, meeting with editors and students and business leaders, and participating in panel discussions at the Alaska Forum on the Environment.

His focus was an international study that outlined the devastating impact of warming climate and melting ice across the North. Commissioned by the Arctic Council, the study was the work of 300 scientists from 18 countries, with Corell serving as one of the lead coordinators. The public overview of the report, released in October, received international media coverage.

Among its 10 major findings: The Arctic will warm and change much faster than the rest of the world.

Corell said the detailed 1,200-page scientific version of the report is almost finished and will be released in a few months.

Dozens of the 150 sessions at the environment forum, including several involving Corell, touched on the impact of these warming temperatures on northern regions, as well as a related problem of contaminants reaching the Arctic through air and water currents, then entering the food chain.

Excessive greenhouse gas emissions by the United States -- blamed by many scientists as the major factor in global warming -- directly threaten the human rights of Arctic residents, said Sheila Watt-Cloutier, chair of the Inuit Circumpolar Conference, during a panel on contaminants and climate change. The group plans to petition the Inter-American Commission on Human Rights to hold hearings and investigate.

"The Arctic is the globe's barometer, and we are the planet's early warning system," she said. "I always say if you protect the Arctic, you protect the planet."

One unexpected consequence of Alaska's warmsummer interfered directly with summer foodgathering in the Interior, said another member of the panel, Craig Fleener, with the Council of Athabascan Tribal Governments. Parts of the Yukon Flats region saw only about a half-inch of rain -- and that caused rivers to fall to levels where they could not be navigated.

"The problem was that we could not get to places that we needed to go," Fleener said. "Thecommunity of Birch Creek was nearly landlocked."

In his own presentations, Corell said that analysis of air sampled from ice cores in Antarctica shows a close match between greenhouse gas concentrations and average global temperatures over the past 400,000 years. The difference between a full ice age and the sort of warm interglacial period now on Earthappears to be only about 10 degrees Fahrenheit, Corell said.

To get a sense of scale, he said, consider that supercomputer models predict parts of the globe could warm as much as 18 degrees before the end of the century.

"Things are going to get pretty warm up here," he said.

Similar studies of ice cores, tree rings and sediment show that global temperatures spiked beginning with rapid industrialization in the 1700s to 1800s, when greenhouse gases like carbon dioxide began to rise.

Such climate shifts are now changing the ecosystem faster than plants and animals can respond -- stressing trees in Alaska's Interior, triggering insect outbreaks like the spruce bark beetle in the Southcentral region, and threatening to push Arctic species like the polar bear toward extinction, climate scientists have warned.

They will also bring unwanted immigrants. West Nile virus, for instance, first showed up in the Lower 48 in 1999 but has since spread north into Canada along the same track as the most dramatic summer warming, Corell said.

Alaskans should not be surprised to see birds carrying the disease as soon as this summer, he said during a speech at the University of Alaska Anchorage.

"Things are happening really fast compared to anything we've seen in the ecosystem for a really long time, maybe 65 million years, since the last major extinction," he told the UAA audience.

Members of Congress and the Bush administration are now beginning to take the climate impact assessment seriously, Corell added. He met recently with Alaska Sen. Ted Stevens and provided him with copies.

But he argued that the time has come for individual people to start cutting emissions of greenhouse gases, regardless of actions by the U.S. government or major corporations.

In an interview, Corell said he's pushing the idea of a national "climate aware" campaign where people will reduce their energy consumption bit by bit -- putting up storm windows, deciding to walk instead of drive, lowering thermostats, and buying products from companies that also reduce emissions.

The scientist likened the campaign to the 1970s movement against pollution that led to a recycling ethic. The goal is to cut greenhouse gases produced in the United States by 10 percent over the next five to 10 years.

"We have to work together to bring down our energy requirements," Corell told the UAA audience. "If you did that, you will save that 10 percent of energy in some bill. So it's in your best interest anyway."

Daily News reporter Doug O'Harra can be reached at do'


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Copyright © 2005 The Anchorage Daily News (

Subject: MSU data

Based on the MSU data presentation today, I would be interested to hear what the consensus is on the data. Is the value that Phil suggested of +0.1 K per decade (with an error around +/- 30%) something that would be considered a middle-of-the-road best guess Thanks, Todd

Subject: Re: MSU data

Hi Todd, I am back from my meeting and will give an update on Tuesday. Roger P.

Subject: another discussion of the ocean heat budget issue (fwd)

This link was sent out and it provides a valuable summary of ocean-atmosperic coupling.

Dallas will add to our ocean heat budget list. Roger P.


Subject: Fw: levitus

Hi Class, Here is a new paper on ocean heat content. We will discuss Tuesday.

Roger P.

P.S. Please use their data to estimate the Earth's radiative imbalance

Subject: land-cover/land-use change data sets

Hi Class, We will be discussing land-use/land-cover data sets later this semester. Dallas will list under this topic on our web site --

Roger P.

Two new papers on ocean warming

Bengtsson, L., V.A. Semenov and O.M. Johannessen, 2004: The early twentieth-century warming in the Arctic - a possible mechanism. J. Climate, 17(20), 4045-4057. PDF

Johannessen, O.M., L. Bengtsson, M.W. Miles, S.I. Kuzmina, V.A. Semenov, G.V. Alekseev, A.P. Nagurnyi, V.F. Zakharov, L.P. Bobylev, L.H. Pettersson, K. Hasselmann, and H.P. Cattle, 2004: Arctic climate change: observed and modelled temperature and sea ice variability. Tellus , 56A, (4), 328-341. PDF

Subject: Fw: GRL paper (fwd)

Hi Class, Syd Levitus sent me this paper along with the figure (JPG of Figure). Roger P.

Boyer, T.P., S. Levitus, J.I. Antonov, R.A. Locarnini, and H.E. Garcia, 2005: Linear trends in salinity for the World Ocean, 1955-1998. Geophys. Res. Letts., 3, L01604, doi:10.1029/2004GL021791. PDF

Subject: Tuesday's class

Hi AT 786, Tomorrow we will continue to discuss the ocean heat content trends, based on the new information over the last week. We will also continue the tropospheric temperature trends, and introduce stratospheric trends. If we have time, we will begin the surface trend discussion. Please send Dallas any papers etc. to post for tomorrow. Roger P.

Subject: populating data sources for climate metrics

Hi AT 786, We have a good start on providing links to sources of current data for several of the climate metrics. Please spend some time searching the web
for more. Ones we need include permafrost data, glaciers, vegetation greenness, land cover/land cover change and plant/animal changes. We could
use more for tropospheric temperature and surface temperature changes, of course. Roger

Subject: class presentations

Hi Jana, Phil, Toshi, and Jacob- Please give us a brief update tomorrow on the status of obtaining the materials for your talk. Did I leave anyone off? Anyone else (siting in, audits) who would like to contribute a talk?

1. Jana Heisler- changes in precipitation frequency and amounts
2. Phil Klotzbach- changes in tropical cyclone frequency and intensity
3. Toshi Matsui - aerosol indirect effect - does the global average (W/m2) matter for climate?
4. Jacob Jawson - regional land use change, specifically Germany

Subject: Glacier webpage

Hi all. Here's a webpage that monitors three "benchmark" glaciers in the United States. These glaciers are as follows: Gulkana and Wolverine Glaciers in Alaska and South Cascade Glacier in Washington. The webpage provides summary graphs of mass balance, air temperature and stream runoff. Here's the link to the webpage:

Here's a webpage from the State of the Canadian Cryosphere site. It contains current snow cover and snow water equivalent conditions for North America:


Subject: Re: class presentations

Hi, all, This is the website of Remote Sensing Researh (RSS). This private company provides "free" satellite (microwave) data, including air temp, water vapor, SST. They have long-term anomalies data in text file, too. Toshi

Subject: Re: populating data sources for climate metrics

Hi All, These websites provide information on land cover, and vegetation greenness. Lixin

Subject: class talks

Hi Class

I am planning that the class presentations (the projects) will be given on Tuesday May 10th starting at 10am. We have four as of now. Plan for a 20 minute presentation with 10 minutes for discussion. This is exam week, so let me know if this time conflicts with any of you. There will be no class the week of May 2nd, and this May 10th time will be the replacement time. I am looking forward to what we find out in the studies. Roger P.

Subject: Re: ocean heat summary

Hi, all: As I said last class, my idea is ocean heat content and lower-tropospheric temperature trend does not agree well.

Let's discuss this issues from the ocean surface energy budget eq. Heat increase in ocean is represented as

dH = Rn(in) - Rn(out) (0)

, where Rn(in) is incoming energy, Rn(out) is outgoing energy
This can be further subdivided to
Rn(in) = SW + emiss1*boltsman*Tair^4 (1)
Rn(out) = A*SW + emiss2*boltsman*Tocean^4 + LH + SH (2)

Combined them...
Rn(in) - Rn(out) = (1-A)*SW + emiss1*boltsman*Tair^4 - emiss2*boltsman*Tocean^4 - LH - SH (3)

where A is ocean surface albedo, SW is downwelling shortwave radiation at ocean surface, emiss is emissivity, boltsman is stefan bolstman constant, Tair is air temperature right above the ocean surface, Tocean is ocean surface temperature, LH is surface latent heat flux, SH is surface sensible heat flux.
Equation 1 is actually simplified form.

Hypotheses of Green-house-gas (GHG) warming on ocean is that GHGs in the air additionally trap the outgoing thermal radiance. Then, increased lower-tropospheric temperature let ocean cooling process inefficient. E.g., Tair increase first, ASSUMING every other factor in (3) are constant. As a result, dH increases in (0).

Bob Stevenson argued that such dH can be quickly offset by the increased LH. So, there is no GHG effect ocean. It is just internal oscillation of ocean circulation.

I also found that there is no consistent anomaly trend between ocean heat content (Levitus 2005) and lower troposphere temperature (Christy et al. 2000. Actually, I need to look only over ocean in detail). There is negative or no trend of air temperature over tropics ! If this discrepancy are true(!?), it means that decadal variability of ocean heat content are controlled by other term, such as SW, LH+SH. SW can be strongly affected by the cloud cover, and Sun have long-term oscillation, too. If surface wind change, LH+SH also changes. You can add the continental river discharge in the eq. (1), too. Efficiency of hydrological cycle (evaporation->condensation->cloud->rainfall) also affect theses terms differently.

Again, initial GHG hypotheses (and linear trend + global W/m2) are too simple to describe decadal variability of ocean heat content. Actually, none of the climate model replicate decadal variability of ocean heat content well. No one can physically explain result in Levitus et al. 2005. (How about Barnett et al. ?) Toshi

Subject: ocean heat summary

Hi Class, Here is my take-away message on the ocean heat budget data:

1. The vast majority of a planetary radiative imbalance involves heat storage changes in the oceans.

2. Over the lass 50 years, the long term average change corresponds to a global radiative imbalance of about 0.3 W meter squared.

3. There is large inter-annual and interdecadal variations in the heat storage, however; the reasons for this have not been explained.

4. There are discrepancies in the ocean heat storage data analyses. The Willis et al data shows that most the heat storage during his period of study was concentrated in the Southern Hemisphere ocean centered at 40S. The Levitus et al data found most the heat storage changes were in the Atlantic Ocean. This difference could be associated with different time periods of analysis. If the time periods were different, but the data sampling spatially representative, however, it suggests a geographic temporal variability that is not understood at all.

5. The climate consequences of the storage of heat below the surface needs to be evaluated. Such "sequestering" of heat removes it from a direct short-term feedback into the atmosphere, such as through the evaporation of water from the sea surface.

Please add to/suggest revisions/etc. Roger P.

Subject: stratospheric temperature trend summary

Hi Class, My take-away message on the stratospheric temperature trends are:

1. There has been a cooling over the last several decades but it involves drops after major volcanic eruptions, while it is more-or-less level between events except that the level is lower afterwards. In the last few years, the global averaged temperatures in the stratosphere have been relatively constant.

2. The changes in stratospheric temperatures are, therefore, inadequately represented by linear trends.

Roger P.

Subject: Tuesday class

Hi Class, On Tuesday, we will discuss the url information sent out to us from class members. Please be prepared to lead that discussion for the ones you sent to us. I will also continue the surface temperature discussion. Roger P.

Subject: Re: ocean heat summary

Hi Toshi, Good summary. Please briefly present on Tuesday. Roger P.

P.S. No word back yet from Dr. Barnett.

Subject: NRC book

Hi Class, Thanks for a very good discussion today! Below, I have provided the link to the NRC book, which will now become our reference source (the book by Bill Cotton and I will still be made available to you, and we will discuss its focus in a few weeks). The NRC book (and the Cotton and Pielke book) are not comprehensive on the metrics we are discussing but do provide a framework for our class. We will discuss Chapter 1 on Tuesday March 22nd when we return from Spring break. Meanwhile, enjoy the time off from classes next week! Also, if you find any other glacier results, please pass them to us. The ones Phil found and presented today were very insightful. We will also continue discussing the surface temperature record.

National Research Council, 2005: Radiative forcing of climate change: Expanding the concept and addressing uncertainties. Committee on Radiative Forcing Effects on Climate Change, Climate Research Committee, Board on Atmospheric Sciences and Climate, Division on Earth and Life Studies, The National Academies Press, Washington, D.C.,

Dallas also has a copy available that you can borrow for photocopying purposes in Room 207 of the Atmos. Annex.

Roger P.


Subject: FYI: 'Hard evidence of climate changes' emerges in northeast US

This story was printed from
'Hard evidence of climate changes' emerges in northeast US
Published on 11-Mar-2005

The climate in the north-eastern parts of the USA has changed significantly, with those changes accelerating over the last 30 years, according to scientists. Using long-term data on temperature,precipitation, frost dates, snowfall, bloom dates and other annually measured occurrences, experts from Clean Air: Cool Planet (CAAP) and the Climate Change Research Centre at the University of New Hampshire (UNH) pinpointed changes to the region's climate in their report, Indicators of Climate Change in the Northeast.

"This report is probably the first to present a picture of how dramatic changes are occurring across a region of the US using a broad range of key indicators," executive director of CAAP Adam Markham stated.

"When data from all of these natural sources are viewed together, they are remarkably consistent, showing that warming is occurring and that it has been changing the climate in our region for some time."

New evidence for climate change uncovered by the report includes:

* A significant decrease in snowfall (up to 60 inches annually)
* A decrease of 16 days with snow on the ground over 30 years
* Lake ice-out dates earlier by nine days in northern and mountainous regions and 16 days in southern parts of the region
* An average advance in spring bloom dates of between four and eight days

Climate researcher from UNH Cameron Wake said that the data also clearly showed an accelerating pace of change over the last 30 years.

"The consistency of change across the region in a number of these indicators is particularly important, because this is what has not been shown before," he explained. "This is clearly the canary in the coal mine in terms of climate change for the north-east."

He added that most of the data had been collected by various government agencies for decades but that some had never before been analysed for trends and there had not been a previous effort to publish the trends together.

The first hard evidence of climate change occurring in the oceans was unveiled in a report by scientists in California last month (see related story), but this is the first time that proof has been shown on land in the US.

Dr Markham said that the straightforward presentation of the science in the report was important to its relevance.

"There is no speculation here," he stated. "This is hard evidence of real climate changes. The negative consequences of these changes will eventually be seen I impacts on air quality and the health of our region's people as well as on our agriculture, winter sports economy and our most precious ecosystems."

"Taken together, these indicators provide a clear case for action to cap and control the emissions of greenhouse gases."

By Jane Kettle
© Faversham House Group Ltd 2005. edie news articles may be copied or forwarded for individual use only. No other reproduction or distribution is permitted without prior written consent.

Subject: Wigley & Meehl et al. in Science for the IPCC

Hi Class, We will discuss tomorrow. Roger P.

  • Meehl, Gerald A., Warren M. Washington, William D. Collins, Julie M. Arblaster, Aixue Hu, Lawrence E. Buja, Warren G. Strand, Haiyan Teng, 2005: How Much More Global Warming and Sea Level Rise? Science, Vol. 307, No 5716, 1769-1772, March 18, 2005. PDF
  • Wigley, Tom M.L., 2005. The Climate Change Commitment. Science, Vol. 307, No 5716,1766-1769. PDF
  • Wigley, Tom M. L., and Sarah C. B. Raper, 2005. Extended scenarios for glacier melt due to anthropogenic forcing. Geophys. Res. Lett., 32, L05704, doi:10.1029/2004GL021238 PDF


Hi Class, FYI Roger P.

Gretchen Cook-Anderson
Headquarters, Washington March 23, 2005
(Phone: 202/358-0836)

Lynn Chandler
Goddard Space Flight Center, Greenbelt, Md.
(Phone: 301/286-2806)

RELEASE: 05-084


NASA continues to explore the impact of black carbon or soot on the Earth's climate. NASA uses satellite data and computer models that recreate the climate. New findings show soot may be contributing to changes happening near the North Pole, such as accelerating melting of sea ice and snow and changing atmospheric temperatures.

Dorothy Koch of Columbia University, New York, and NASA's Goddard Institute for Space Studies (GISS), New York, and James Hansen of NASA GISS are co-authors of the study that appeared in a recent issue of the Journal of Geophysical Research.

"This research offers additional evidence black carbon, generated through the process of incomplete combustion, may have a significant warming impact on the Arctic," Koch said. "Further, it means there may be immediate consequences for Arctic ecosystems, and potentially long-term implications on climate patterns for much of the globe," she added.

The Arctic is especially susceptible to the impact of human-generated particles and other pollution. In recent years the Arctic has significantly warmed, and sea-ice cover and glacial snow have diminished. Likely causes for these trends include changing weather patterns and the effects of pollution. Black carbon has been implicated as playing a role in melting ice and snow. When soot falls on ice, it darkens the surface and accelerates melting by increasing absorbed sunlight. Airborne soot also warms the air and affects weather patterns and clouds.

Koch and Hansen?s results suggest a possible mechanism behind the satellite- derived observations of Arctic climate change. They found the timing and location of Arctic warming and sea ice loss in the late 20th century are consistent with a significant contribution from man-made tiny particles of pollution, or aerosols.

Koch and Hansen used GISS' General Circulation Model (GCM) to investigate the origins of Arctic soot by isolating various source regions and types. The GCM employs a lot of different data gathered by NASA and other U.S. satellites to study many environmental factors such as ice cover and temperature.

The research found in the atmosphere over the Arctic, about one-third of the soot comes from South Asia, one-third from burning biomass or vegetation around the world, and the remainder from Russia, Europe and North America.

South Asia is estimated to have the largest industrial soot emissions in the world, and the meteorology in that region readily lofts pollution into the upper
atmosphere where it is transported to the North Pole. Meanwhile, the pollution from Europe and Russia travels closer to the surface.

This study demonstrates the GCMs accurately represent the long-range transport of pollutants, such as those from Southern Asia to the Arctic, that were observed from aircraft.

During the early 1980s the primary sources of Arctic particulate pollution are believed to have been from Russia and Europe. Those sources have decreased
substantially in the past two decades, but the computer simulations indicate increasing emissions from South Asia have made up for some of the reduced
Eurasian pollution. Koch and Hansen suggest Southern Asia also makes the greatest contribution to soot deposited on Greenland.

NASA sponsored efforts using satellite data and models to assess polar feedbacks constitute an important contribution to the U.S. Climate Change Science Program. By exploring processes in the Earth?s atmosphere, NASA scientists are seeking answers to how pollutants like soot are changing the climate of the world around us.

For more information and images related to this story on the Internet, visit:

For information about NASA and agency programs on the Web, visit:

Subject: One More Thing To Worry About? (fwd)

Hi Class, More information to digest. Roger P.



Nature 434, 435 (24 March 2005)

Consumer law is used to attack climate findings

Sir - Your News story "Salt sellers challenge US health agency using data-quality act" (Nature 433 671; 2005), suggests that a lawsuit filed by the Salt Institute represents "the first time that a petitioner has actually sued under the Data Quality Act". This is not the case, although the ruling that the Salt Institute is appealing was the first verdict given in a case brought under the federal Data Quality Act.

In August 2003 a conservative advocacy group, the Competitive Enterprise Institute, filed a suit claiming violations of the act against President George Bush and John Marburger, director of the White House Office of Science and Technology Policy (OSTP). The most important claim was that reports by the US National Assessment of the potential consequences of climate change (USNA) used results from two different global climate models to construct scenarios of future climate (see National Assessment Synthesis Team, Climate Change Impacts on the United States, Cambridge Univ. Press, Cambridge, 2000) -- which therefore violated the act because one of the two scenarios had to be in error.

In November 2003, just as the Department of Justice was preparing to file its response, the parties accepted a ruling of "dismissal with prejudice", meaning that the lawsuit could not be refiled. Although the Department of Justice did not release its brief, it had apparently made a strong argument against the absurd notion that projections of the future must be proven accurate in advance.

The OSTP nonetheless ordered that a notice be added to USNA web pages, indicating that the reports "were not subjected to OSTP's Information Quality Act Guidelines". This implies that the USNA report was not properly reviewed and would not meet the OSTP guidelines. This is misleading at best, as the report was subjected to a four-stage review that was more comprehensive than called for by the act. In addition, the OSTP guidelines did not exist or apply at the time that the USNA was released.

Attempts by the USNA's lead authors and contributors (including myself) to get this notice removed or modified have failed, leaving in place an unfair criticism of the assessment's widely accepted findings.

Michael C. MacCracken
Climate Institute, 1785 Massachusetts Avenue NW,
Washington DC 20036, USA

Subject: Re: Letter in Nature: MacCracken vs CEI, again (fwd)


Hi AT 786, FYI; please be preapred to discuss Tuesday also.

Roger P.


---------- Forwarded message ----------
Date: Thu, 24 Mar 2005 12:38:34 -0500
From: Mike MacCracken <>
To: Timo Hämeranta <>

Subject: Re: Letter in Nature: MacCracken vs CEI, again

Dear Timo--

Your analysis is flawed in so many ways it is hard to list them all, but to just start:

1. The guidelines being referred to were not in effect at the time the report was put out; therefore, the guidelines about the review process that they call for could not be followed--they did not exist at the time. One might as well say that the US Constitution was not subject to the Act.

2. In any case, the assessment report went through a more complete (i.e., 4-stage) review than the Act's guidelines call for--so the statement is really simply incorrect as well as inappropriate and applied after the fact.

3. The assessment report specifically says that the model "[s]cenarios are not specific predictions or forecasts." So, suing with the claim that they are not accurate predictions would seem to show that the report has not been read. I would hope, in fact, we could all agree that no scenarios of the future by anyone can be claimed to be accurate predictions in the sense that we evaluate data about the past--they are plausible projections of what could happen under a given set of circumstances (e.g., an emissions scenario). Some of us might develop scenarios using physically based models, and others by doing a trend analysis from the past and others in some other way--none of these approaches should be claimed to be anything but plausible projections of the future--they are not data. Recognizing this, the Act we are talking about is the Federal Data (DATA!!!!) Quality Act--it is about DATA--and data are from the past, not the future. The Act recognizes that future projections are not data--if it did not, there would be a lot of lawsuits being filed complaining that the president's budget projections (or Iraqio war projections) are not accurate, etc. So, the Act is not even applicable to the matter at issue.

4. The projections were for the change in temperature and precipitation over a century, not for a year by year change, so your comparison to what is happening this year or last is simply not applicable. The actual model results include natural variations that could take any year's climate up or down around the rising trend, but, of course, the chaotic behavior of the climate system on the short-term requires that such year by year fluctuations be treated as part of the noise--not the trend.

5. CEI's lawsuit was settled by "dismissal with prejudice", not withdrawal. Too bad the Department of Justice brief in response was not made publicly available--I would imagine it would rather have strongly refuted the CEI claims. By settling the case before the DOJ brief was released, the CEI has, in the absence of the countervailing arguments, been able to keep claiming their lawsuit raised valid issues--nice ploy, but it was dismissed with prejudice, meaning they cannot refile, so they should simply stop making a claim that they at least implicitly acknowledge would not have held up in court. And this applying of a caveat about the report was not part of the court record of the case--just because an administration friend of CEI threw them this inaccurate bone to help them feel better about losing does not make it so. [This same sort of thing happened with regard to the withdrawal of their first lawsuit about the assessment--the letter sent simply stated the obvious--an advisory committee report is not policy; DUH--and again, they settled just before the DOJ was going to file the rebuttal--nice ploy, in that it keeps from the public the response to the shortcomings in their arguments.]

6. As to the Climate Action Report 2002, it went through a full Federal Register and the revised version was then approved on a word by word basis by all of the agencies reviewing it (and I know because I handled all the various comments on this word and that word). With the CEI claim against the National Assessment dismissed with prejudice, the claim against the Climate Action Report is negated as well. Note, of course, that the US has not
withdrawn this submission from the UNFCCC, and in a Senate hearing in July 2002, CEQ director Connaughton responded (as I recall for, conveniently for
the Administration, I have not been able to find the published transcript of the hearing on the Web) to a question from Senator Kerry about the science described in the impacts chapter as it all being well-established (and I agree with him on that--that chapter focused only on what was well-established and not on various of the less well-established results). I do hope you have actually read that chapter (in fact, some of what CEI complained about was really from the 2001 report of the National Research Council done at the request of President Bush, and the NRC reports are often
indicated as the "gold standard' by the Administration--so CEI should be complaining to the NRC).

7. The CEI calls for the next National Assessment report to be subjected to the Federal Data Quality Act. Well, this Administration has not, as far as I
know, chosen to do an assessment (one might say they are in violation of the Global Change Research Act). One would think that if they feel the first
assessment was flawed, they would be sponsoring another one to replace it. But no, they are leaving it as the most complete set of materials on which to rely--so for the IPCC Fourth Assessment, as for the Third Assessment, the National Assessment will be the expert base of information. Everyone awaits
this Administration focusing on impacts and facing up to the changes actually occurring. In any case, whether the FDQA will be applicable will
depend on how preparation of the report is organized--if it is done the way the last one was, with a federal advisory committee, it is not obvious to me
(and I am not a lawyer) that the FDQA applies--read the Act and you tell me. If the FDQA does apply to advisory committee reports, then its application
ought to be to all advisory committee reports--and this has not been the case, as far as I know. If it is done by the agencies themselves, then
indeed, the FDQA should be applied if the other various conditions are met. [I should note that when you read the Act, while you do find a requirement
for review, there is not a requirement that anyone or agency pay attention to the review comments or explain why they do or do not make a change--not really as tough a review as independent peer-review by a journal, in my view.]

8. We all also await the next Climate Action Report, due later this year. I do hope it is subject to FDQA--I would not want this Administration to not pay attention to the facts of increasing emissions despite the US Senate-approved commitment to the UNFCCC provision calling for actions to return emissions to the 1990 level.

9. And as to the current temperature trend, just move up to Alaska and experience the changes occurring. Or, if you do not want to move there, at least read the book "The Whale and the Supercomputer" to get a sense of what is happening.

Best, Mike

From: Timo Hämeranta <>
Date: Thu, 24 Mar 2005 18:01:19 +0200
To: "Michael C. MacCracken" <>

Subject: Letter in Nature: MacCracken vs CEI, again

Dear Mike,

I notice that you in Nature today still lament that "In August 2003 a conservative advocacy group, the Competitive Enterprise Institute, filed a suit claiming violations of the act against President George Bush and John Marburger, director of the White House Office of Science and Technology Policy (OSTP). The most important claim was that reports by the US National Assessment of the potential consequences of climate change (USNA) used results from two different global climate models to construct scenarios of future climate (see National Assessment Synthesis Team, Climate Change Impacts on the United States, Cambridge Univ. Press, Cambridge, 2000) - which therefore violated the act because one of the two scenarios had to be in error.

Attempts by the USNA's lead authors and contributors (including myself) to get this notice removed or modified have failed, leaving in place an unfair criticism of the assessment's widely accepted findings." Ref: MacCracken, Michael C., 2005. Consumer law is used to attack climate findings. Nature Vol. 434, No 7032, p. 435, March 24, 2005PDF 

Well, CEI press release Nov 6, 2003 states that "The White House Office of Science and Technology Policy has publicly acknowledged that the National Assessment on Climate Change was not "subjected to OSTP's Information Quality Act guidelines." This acknowledgement now appears prominently on the document posted on the U. S. Global Change Research Program's web site ( With this admission, the Competitive Enterprise Institute has withdrawn its complaint in federal court that the National Assessment did not meet the minimal scientific standards required by the Federal Data Quality Act.

A subsequent product disseminated by the Environmental Protection Agency, Climate Action Report 2002, repeats many of the scientifically unsupportable assertions contained in the National Assessment and should now be subjected to FDQA guidelines, as should the next National Assessment due in October 2004.

CEI argued in its complaint that the National Assessment violates legal requirements of objectivity and utility by employing computer models proven unreliable and by revising past climate history to incorrectly portray 20th century climate as unusual.

"We are pleased to see that the federal government has now put the public on notice that the National Assessment is propaganda, not science," said Myron Ebell, Director of Global Warming Policy at CEI. "The next report must meet the minimal scientific standards required by the Federal Data Quality Act."


Well, dear Mike, it's human that for this incident you, the lead author, have painful memories for the rest of your life. But, scientifically, your protests are unjustified.

You have participated in Climatesceptics discussions for years, sent me the National Assessment Overview, and most importantly, you have all the time stressed that climate modellers do not make predictions, but only projections.

Projections are not predictions of what will happen, only results of the parameters put in models. And everything influencing and affecting climate is not parameterized, yet.

Current models are unable to predict anything.

Therefore the universal criticism which CEI presented was and still is fair and justified.

Btw, your National Assessment 2000 projected temperature increases in U.S., but reality has already proved the projections flawed.

From 1998 on the U.S. temperature has decreased, please see

NASA News release Feb 8, 2005 online

All the best, Timo

Subject: MacCracken on GW

Hi Class, More on this discussion. Roger P.


Date: Thu, 24 Mar 2005 20:05:15 +0200
From: Timo Hämeranta <>
To: 'Mike MacCracken' <>

Dear Mike, when I referred to the new results that from 1998 on U.S. temperature has cooled, you argue that "as to the current temperature trend, just move up to Alaska and experience the changes occurring".

Well, climate changes all the time, there's nothing 'unprecedented' or unusual in Alaska or elsewhere.

Current GCMs are unable to catch or project these local changes.

You have correctly stated that "We strongly agree that much more reliable regional climate simulations and analyses are needed. However, at present, as the News story makes clear, such simulations are more aspiration than reality."

Ref: MacCracken, Michael, Joel Smith and Anthony C. Janetos, 2004. Reliable regional climate model not yet on horizon. Nature Vol. 429, No 6993, p. 699,
June 17, 2004. PDF

Best, Timo


Timo Hämeranta, LL.M.
Moderator, Climatesceptics
Martinlaaksontie 42 B 9
01620 Vantaa
Finland, Member State of the European Union

Subject: Re: [Drought] Re: Interesting Streamflow Info - Are We Drying Out Nationally?

Hi All, Information on the current conditions in the northeast US (excerpted from an e-mail to the drought e-mail list), which to juxtapose with the
information from Cornell on earlier springs. Roger P.


---------- Forwarded message ----------
Date: Mon, 28 Mar 2005 11:28:49 -0500
From: Douglas Lecomte <>
To: Tom Pagano <>
Cc: Richard Heim <>,
Subject: Re: [Drought] Re: Interesting Streamflow Info - Are We Drying
Out Nationally?

Tom and others,

Actually, the shorter term trend is toward much wetter conditions, and hopefully our stock portfolios will recover as well.

I should point out that the low flows shown for the Northeast could be very misleading, as they are apparently due to the lateness of the winter season.
When the anomalous snowpack melts, you will see those flows rise quickly, and the current rain event may just do the trick. Driving down from the Berkshires a few days ago, I was struck by the amount of snowpack still left in the Hudson Valley and western MA this late in the season. Terrific news for ski resort operators, who had plans to go well into April even in the southern Berkshires, which is pretty unusual. The current rains, however, may literally put a damper on some of those plans, and certainly raises the risk of flooding. Croton Reservoir, BTW, north of NYC, still appeared to be frozen over.

Subject: class presentations

Hi Class, It is time to finalize the schedule for your talks. Please confirm with Dallas and I the day you would like to present. Any of our Tuesday's will work, of course, if you do not want to wait to present on Tuesday May 10th (340 pm-540 pm is the time alloted for our class in Exam week by the University, but we are changing to 10 am that day, unless any of you have a conflict with that time).

There will be no class May 3rd, so we should finalize class conclusions on the climate metrics on April 26th.

Roger P.

Read the Editorial Essay by James E. Hansen, 2005: A slippery slope: How much global warming constitutes "Dangerous anthropogenic interference?", Climatic Change, 68, 269-279. PDF

  • Tuesday, March 29, 2005

Lu, Lixin, 2005: Introduction to Vegetation Index Data Set (NDVI) Available from AVHRR, MODIS, and SPOT. View the Presentation PDF

Subject: Northeast United States Climate Report

Recently, Dr. Pielke sent us a link to a press release about a report entitled "Hard evidence of climate changes' emerges in northeast US". One of the claims in this press release was that there has been a significant decrease in snowfall in the northeast United States, which has accelerated over the past thirty years. I was pretty sure that this was not the case, so I did some research into the numbers. I have attached the email that I sent to Dr. Wake, the lead climate researcher on this project, to the bottom of this email. I thought I'd keep the class posted on this dialog.



Dear Dr. Wake,

Good afternoon. It was with great interest that I read the press release of your report entitled "Indicators of Climate Change in the Northeast". Having grown up in Plymouth, Massachusetts, I always try to keep up with the climate and weather in the New England area. In the press release that I viewed, it indicated that changes in climate in the northeast United States have accelerated over the past 30 years, including significant decreases in snowfall in the northeast United States.

I gathered seasonal snowfall data over the past thirty years from seven cities in the northeast United States (Philadelphia, New York City (Central Park), Providence, Boston, Burlington, Concord and Caribou). When I ran linear trends on their snowfall over the past thirty years (from the winter of 1973-1974 through the winter of 2002-2003), I did not find any significant decrease in snowfall. In fact, of the seven cities, four of them actually showed an increasing snowfall trend. Here are the linear trends per decade according to my calculations:

Boston: +2.0" per decade
Providence: +0.7" per decade
Concord: -0.8" per decade
Burlington: +2.2" per decade
Caribou: -1.4" per decade
New York City (Central Park): +0.7" per decade
Philadelphia: -1.7" per decade

I have attached the MS Excel spreadsheet that I used to make my calculations to this email. I am interested in any comments that you might have. Thank you very much for your time.


Phil Klotzbach
Research Associate
Colorado State University


Subject: Re: Northeast United States Climate Report

Thanks Phil! Hopefully you will receive a response quickly. You could also
send to Prof Dave Robinson at Rutgers who is a leading scientist on snow
cover trends.


Subject: surface temperature trends - my summary

Hi Class, Following is my take-away message on the surface temperature issue with respect to assessment of climate change:

1. surface temperature is a poor metric to apply to monitor "global warming" (or cooling). Ocean heat content changes are much more appropriate as that is where most of the heat is stored, and where radiative imbalance can be diagnosed most directly.

2. In using surface temperature trends, the spatial representativeness of the observing sites used to compute regional and global averages have not yet properly addressed all of the issue of data homogenization. This includes the influence on the trends of surface air absolute moisture changes (moist enthalpy) and of station siting (the microclimate exposure change over time).

3. The attribution of even spatially representative regional and global surface temperature changes has not adequately considered all important climate forcings and feedbacks, such as land-use/land-cover change and the multiple climate effects of aerosols.

4. The use by policymakers of a global-averaged surface temperature grossly misses the climate metrics that are much more important to society (such as long term atmospheric circulation changes; alterations in precipitation due to landscape and aerosol-induced microphysics changes).

5. The debate over the globally-averaged surface temperatures in the 1990s relative to the last 1000 years should be resolved using the same data
(i.e., proxy data) for the entire period of record. As stated under #4 this is not a very useful climate metric for the most important climate influences on society, but is still a scientific question that should be resolved.

Let me know if you have items to add to this list, or disagree with any of them.



Subject: discussion for tomorrow

Hi AT 786, Please come to class prepared to discuss if the IPCC and US National Assessment provide predictions or not. Roger P.


  • Tuesday, April 5, 2005

For class today

  1. Tables provided by Norm Wood, Colorado State University PDF
  2. Figures provided by Norm Wood, Atmospheric Science Dept, Colorado State University PDF
  3. Section 8.3.8: Assessment of the Relative Radiative Effect of Carbon Dioxide and Water Vapor from the 2nd edition of Human Impacts on Weather and Climate, in preparation PDF
  4. MacCracken, M., 2002: Do the uncertainty ranges in the IPCC and U.S. National Assessments account adequately for possibly overlooked climatic influences. Climatic Change, 52, 13-23. PDF
  • Wednesday, April 6, 2005

Check out the following papers and presentations suggested by Roger Pielke Sr. !


Subject: paper on long term surface temperature record

Hi Class

The new paper listed below adds to the discussion of the surface temperature record.

Roger P.


"Examination of large-scale millennial-long temperature reconstructions reveals a wide range of datasets and methods used for calibration. Proxy timeseries are commonly calibrated against overlapping instrumental records, representing different seasons, latitudinal fractions of the Northern Hemisphere, and including or excluding sea surface temperature data. Methodological differences include, using scaling or regression, the calibration time period, and smoothing data before calibration. We find that these various approaches alone can result in differences to the reconstructed temperature amplitude of about 0.5°C. This is on the order of variability displayed in the last IPCC report for temperature change over the past millennium. A more precise assessment of absolute reconstructed temperature amplitudes is necessary to help quantify the relative influences of various forcings in climate models."

Esper, Jan, D. Frank, Rob J.S. Wilson, R.J.S. and Keith Briffa. Effect of scaling and regression on reconstructed temperature amplitude for the past millennium. (Geophysical Research Letters, accepted January 2005)

Subject: for Tuesday's class

Hi Class, On Tuesday, we will continue to discuss the importance of land use/land cover change as a climate metric. I will discuss the linkage to local, regional and global climate, based on

Pielke Sr., R.A., 2001: Influence of the spatial distribution of vegetation and soils on the prediction of cumulus convective rainfall.
Rev. Geophys., 39, 151-177.

We also will look at the web sites


Tomorrow in class Phil will also present his analysis of the northeast snow data. Roger P.

Kirsten Koehler will discuss the following two papers in class tomorrow Tuesday, April 12. They are interesting papers on predictions of airborne dust in the future under 6 different scenarios and another on the influence of mineral dust on

1. Mahowald,.N.M., and C. Luo, 2003:A less dusty future? GRL vol 30 no. 17 PDF
2. Mahowald, N.M., and L.M. Kiehl, 2003: Mineral aerosol and cloud interactions. GRL vol 30 no. 9 PDF

Subject: solar influences on the troposphere

Hi Class, We have not discussed solar influences on the troposphere. Attached is a paper which presents any interesting view of this subject. PDF

Roger P.

Subject: more on the solar-weather research study

Hi Class, Here is another source for solar-weather studies.

Roger P.








Subject: greenness anomalies

Hi AT 786, Here is a very interesting vegetation greeness map. It is from - GIF


Subject: yesterday's class

Hi AT 786, Thank you for excellent presentations by Kirsten, Toshi and Phil. These were very informative! This coming Tuesday, Jana and Jacob have agreed to present. (Sheri - please let us know if you are ready also). I will also continue discussion of the recent url information that was sent to you. Roger P.


Subject: surface temperature trend paper and press release

Hi AT 786, Provided below is a paper on surface temperature trends as well as the AGU press release on this topic. We will discuss Tuesday.

Roger P.

Mann, Michael, Caspar Ammann, Kevin Trenberth, Raymond Bradley, Keith Briffa, Philip Jones, Tim Osborn, Tom Crowley, Malcolm Hughes, Michael Oppenheimer, Jonathan Overpeck, Scott Rutherford, and Tom Wigley, 2003. On Past Temperatures and Anomalous Late-20th Century Warmth. Eos, Vol. 84, No. 27, page 256, July 8, 2003 PDF

Press Release:


Hi AT 786

Here is another paper and news release to discuss. Roger P.


Kohfeld, Karen E. et al., 2005. Role of Marine Biology in Glacial-Interglacial CO2 Cycles. Science Vol. 308, No 5718, pp. 74-78, April 1, 2005 PDF

"It has been hypothesized that changes in the marine biological pump caused a major portion of the glacial reduction of atmospheric carbon dioxide by 80
to 100 parts per million through increased iron fertilization of marine plankton, increased ocean nutrient content or utilization, or shifts in dominant plankton types. We analyze sedimentary records of marine productivity at the peak and the middle of the last glacial cycle and show that neither changes in nutrient utilization in the Southern Ocean nor shifts in plankton dominance explain the CO2 drawdown. Iron fertilization and associated mechanisms can be responsible for no more than half the observed drawdown."

Supporting Online Material: <>


The following is from: <>

"Climate: The oceanic CO2 puzzle

By Dan Whipple

Boulder, CO, Apr. 11 (UPI) -- For years, climate scientists and oceanographers have been struggling to figure out the relationship of carbon dioxide in the oceans to the amount of CO2 in the atmosphere. There is a definite connection, but to date no one has been able to discover what it is.

The only thing for sure is concentrations of atmospheric carbon dioxide have fluctuated naturally by about 80 to 100 parts per million between glacial and interglacial periods during Earth's recent geological history. "The overall conclusion is that CO2 has changed in the past, and at glacial periods it was roughly 30 to 35 percent lower than it was in pre-industrial times," Karen Kohfeld, assistant professor of earth and environmental science at Queens College of the City University of New York, told UPI's Climate.

"This has occurred consistently over glacial periods, at least for the last 800,000 years," Kohfeld said. "Every 100,000 years, we have these time periods where CO2 drops. It drops for natural reasons." The question is: what are those so-called natural reasons? The explanation has eluded researchers for at least the past 20 years, Kohfeld said. One hypothesis suggests a chain of events that begins whenever iron content increases in the oceans. Increased iron fertilizes plankton growth, which enhances the water's ability to absorb CO2, pulling it out of the atmosphere and thereby leading to colder temperatures.

Some years ago, the late John Martin, an oceanographer with the Woods HoleOceanographic Institution, dramatized this hypothesis by saying, "Give me half a tanker of iron, and I will give you an ice age."

Scott Doney, an associate scientist at Woods Hole, told Climate of the attempts to explain the CO2 variability.

"I jokingly call this the Holy Grail of chemical oceanography," he said. "No one has found a single hypothesis to explain the CO2 drawdown."

Still, the biological activity connection carries some credence. Plankton and other ocean plants, just like land plants, ingest carbon from the atmosphere, then die and gradually drift to the bottom of the ocean where they -- and the carbon -- become trapped in sediment. The process removes CO2 from the atmosphere "at least on the time scale of ocean circulation," Kohfeld said. "If marine biology were much more active in the past during these glacial periods, maybe that's what caused CO2 to be lower."

The problem is that scientists using atmospheric computer models have attempted to draw down CO2 during glacial periods by changing the temperature of sea ice, but their calculations have not reproduced the numbers observed from the paleoclimate data.

Kohfeld's work, which was published in the April 1 issue of the journal Science, concluded that ocean biology can explain only about 40 percent of
ocean carbon uptake during glaciation.

Doney said Kohfeld's work presents a couple of scientifically interesting aspects. One has to do with her attempt to draw inferences from "a large number of ice cores. Lots of people have looked at individual cores (but Kohfeld is) trying to look at a whole collection of cores with the same method ... and rather than looking at only the height of the last glacial maximum, (she is) also looking at the period 80,000 to 100,000 years ago, when something had already happened to cause the (CO2) drawdown."

Based on other data, it appears CO2 levels actually trailed temperatures during interglacial periods, rather than leading them, according to paleoclimatologist Casper Amman of the National Center for Atmospheric Research in Boulder.

"We find that the change of CO2 in particular can explain about half of the climate change between glacial maximum and the Holocene (at the end of the
last Ice Age)," Amman told Climate.

Unlike the current climate situation, where CO2 buildup in the atmosphere is forcing changes in the climate, in the past the situation was probably reversed -- CO2 concentrations were determined by temperature changes. One possibility for the decline in CO2 beyond the uptake from biological processes are physical ones.

When ocean temperatures are colder, the water can absorb CO2 more efficiently, Amman said. "Even without any biology, the colder the ocean gets, the more it dissolves CO2."

Scientists think that during the glacial period the thermohaline circulation -- a global conveyor belt of ocean current that sinks warm water down and brings cold water to the surface -- somehow shut down. It probably did so in some other periods as well, such as the Younger Dryas, which occurred roughly 12,000 years ago.

Amman said recent thinking on this subject is that during the glacial maximums, the thermohaline might have been quite vigorous, though the locations of the cold-water upwellings may have changed. This would continue to bring fresh water to the surface to absorb CO2, while the water saturated with CO2 would be circulated to the deeper ocean.

Kohfeld's paper, he said, which argues that less than half of the CO2 change can be linked to biological activity, may encourage more research into the issue of physical mechanisms for CO2 uptake. Doney agreed.

"In terms of this science question, where we're headed is that there won't be one single mechanism that led to the entire drawdown of atmospheric CO2," Doney said. "A series of different mechanisms occurred at different times. It may have been changes in ocean physics 120,000 years ago, then dust and iron fertilization that led to a further drawdown."

In terms of relevance to current climate issues, Doney said: "There has been a lot of discussion of whether the CO2 problem will solve itself -- where there is some self-regulating mechanism. The resounding answer that's coming out of the research is that there is not any self-regulating systems that are going to clean things up over the next 200 years or so."

Even if there was some attempt to manipulate ocean CO2 absorption -- such as by dumping iron into the Southern Ocean, for example -- "this paper would
call into question the effectiveness of that action," Doney said. "This is another piece of evidence that says maybe the role of iron in the carbon cycle isn't as effective at storing carbon as we might hope."

Regarding Martin's quote about using a half-tanker of iron to jump-start an ice age, he said, "You might be able to draw down CO2, but John couldn't give you a new ice age." "

Subject: climate definitions (fwd)

Hi AT 786, This publication has interesting definitions. We will also discuss. Roger P.


Subject: Fw: Wild Solar radiation budgets: Surface vs. GCMs

Hi AT 786, We have not specfically discussed the skill of GCM "projections" to accurately model the surface, atmospheric and top of the atmosphere (TOA) fluxes. The attached paper provides a discussion of that skill.

The two citations below are also relevant to this discussion.

Kiehl, J.T., and Kevin E. Trenberth, 1997. Earth's Annual Global Mean Energy Budget. BAMS Vol. 78, No 2, 197-208. PDF

Potter, Gerald L., and Robert D. Cess, 2004. Testing the impact of clouds on the radiation budgets of 19 atmospheric general circulation models, J. Geophys. Res., 109, D02106, doi:10.1029/2003JD004018, January 27, 2004. PDF

Roger P.



Subject: Fw: radiation datasets (fwd)

Hi AT 786, Here are data sets on radiative fluxes. The trends are interesting. Roger P.


Hicke, Jeffrey A., 2005: NCEP and GISS solar radiation data sets available for ecosystem modeling: Description, differences, and impacts on net primary production Global Biogeochem. Cycles, Vol. 19, No. 2, GB2006

Subject: global glacier change

Hi AT 786, We have this general web site, but Dallas will add to specifically to our glacier trend section. Roger P.

Subject: more info on glacier trends

Hi AT 786, Dallas will add this information under glacier trends. Roger P.

Roger A. Pielke, Sr., Professor and State Climatologist
1371 Campus Delivery, Department Atmospheric Science,
Colorado State University, Fort Collins, CO 80523-1371,
Phone: 970-491-8293/Fax: 970-491-3314, Email:


Mark Dyurgerov kindly sent me the following comments and the figure below:


"Dear Timo Hämeranta,


Let me make one small comment to the answer of Hartwig Volz. In reality WE DO NOT HAVE "summary statistics on ice advance/shrinkage on a global basis?". Advance/shrinkage IS NOT THE SAME as glacier volume change you have referred to. World Glacier Monitoring Service (Zurich, Switzerland) have published 8 volumes in Fluctuations of Glaciers the most complete data sets for SEVERAL HUNDREDS OF GLACIERS world-wide front-advance/retreats over the previous century. There are some additional data available for other sources. The main problem is that these time series have not been compiled as the continuous time series for every particular glacier. It is difficult and time-consuming job and requires high-level professional to fulfill the task, which includes find all publications, archived data, estimate the accuracy, eliminate gross errors, digitize data and so on.


My another comment concerning mass balance data which you have referred to World Glacier Melt web site. In the January of this year, 2005, I have updated the results you have referred to. These updated results of glacier volume change (do not include Greenland and Antarctic ice sheets, but only mountain glaciers and subpolar ice caps) are posted at web site: To get easy access to these data go to: NSIDC - Data Products and Services - Glaciers/ice sheets - glacier mass balance and regime measurements and analysis, 1945-2003 - Access Data and open Supplement 2005 (also read me firs word file, just one paragraph). In Supplement 2005 there are 6 major tables with global glacier area, mass balance of all known glacier time series, also by systems, regions and global, the paper with explanation on how these data were received and calculated.


As the example on how these updated global glacier volume change looked like I have attached the figure.


Thank you for your job,



Mark Dyurgerov"





Dear Mark, once again, many thanks for your contribution.


Timo Hämeranta, LL.M., Moderator, Climatesceptics, Martinlaaksontie 42 B 9, 01620 Vantaa, Finland, Member State of the European Union


Moderator:, Private:

Subject: For Tuesday, April 26th class

Hi AT 786

On Tuesday we will discuss the Executive Summary, Chapter 7 and any other Chapters of the NRC report. We will also review the metrics we reviewed this semester. Jana, and tentatively, Sheri, will also be giving presentations Tuesday. Finally, let Dallas have the title of your class presentation that several of you will be giving during Exam week.

Roger P.

Subject: Alpine glaciers

Hi AT 786, Here is information on Alpine glaciers that was sent in an e-mail to Timo Hämeranta <> by Hartig Voltz for distribution. Dallas will place under the glacier section. Roger P.


Reproduced from an e-mail sent April 20 to Timo H. and his distribution list.

Date: Wed, 20 Apr 2005 08:38:11 +0200
From: "Volz, Dr. Hartwig" <>
To: Timo Hämeranta <>,

"Here is some information about glacier melting. If you are in search of anthropogenically induced catastrophes, you should read part 1 only. If you are interested in natural variation of climate, feel free to read part 2 in addition. Basically this is a summary of a publication by G. Patzelt, professor at the Institute of High Mountain Research (Institut für Hochgebirgsforschung), University of Innsbruck, Austria. The literature (in German): Rundgespraeche der Kommission fuer Oekologie, vol. 18, "Entwicklung der Umwelt seit der letzten Eiszeit", pp 119-125, Verlag Dr. Friedrich Pfeil, München, June 2000.

Part 1, glacier melting in the Alps

The Alps are located in the Central to Southern parts of Europe and up to 4808m high. Since 1850/55 Alpine glaciers have lost 50% of their area and 60% of their ice volume.

Part 2.1, detailed analysis of melting

The extension of glaciers in the Alps is well documented during this period, either by direct observation or, approximately since 1900, by photographs. An evaluation of this information reveals the following melting periods:

From 1855 to 1890 the glacier retreat amounted to 20% of its area from 1890 to 1925 the area remained constant from 1925 to 1965 an additional 26% of the original area melted down from 1965 to 1980 the area remained constant from 1980 until today an additional 5% or so disappeared.

Part 2.2, temperature variations in the Alps during the Holocene

From the altitude of tree growth limit, from glacier deposits and from atmospheric lapse rate the temperature variation of the Alps during the Holocene (the last round about 10,000 years) can rather precisely be determinated. The results: The amplitude of upper altitude of tree growth varied by about 250m, corresponding to a temperature variation of about 1.5°C. Today's altitude is 160m above the lowest level, corresponding to a temperature of about 0.9 to 1.0°C above minimum or 0.5 to 0.6°C below maximum. During two thirds of the Holocene the temperature was equal or higher than today. 1850 was about the period of highest glacier advance in the Alps during the Holocene. During the Holocene for several times glacier retreat was more pronounced than it is today."

(from a December 2000 communication by Hartwig Volz).


Subject: Fw: [Climate Sceptics] Melting or growing glaciers

Hi Class, Here is more from Timo. This will be listed under glaciers. Roger



Johannes Oerlemans argues in his recent study that "The worldwide retreat of many glaciers during the last few decades is frequently mentioned as a clear
and unambiguous sign of global warming".

Ref: Oerlemans, Johannes Hans, 2005. Extracting a Climate Signal from 169 Glacier Records. Science Express published online before print March 3, 2005

Seidel, Dian J. and Melissa Free, 2003. Comparison of Lower-Tropospheric Temperature Climatologies and Trends at Low and High Elevation Radiosonde
Sites. Climatic Change Vol. 59, No 1-2, pp. 53-74, July 2003 PDF

".... to determine the nature of climate variability at high elevation sites requires local observations, since large-scale patterns derived from low elevation observations may not be representative of the mountain regions. Conversely, temperature change in mountain regions should not be viewed as necessarily representative of global surface or tropospheric trends."

Favier, Vincent, Patrick Wagnon, and Pierre Ribstein, 2004. Glaciers of the outer and inner tropics: A different behaviour but a common response to climatic forcing. Geophys. Res. Lett., 31, L16403, doi:10.1029/2004GL020654, August 27, 2004 PDF


"We have compared the annual surface energy balance (SEB) of Zongo Glacier(16°S, Bolivia, outer tropics) and Antizana Glacier 15 (0°S, Ecuador, inner
tropics). On annual time scale energy fluxes are very similar in the ablation zone: turbulent heat fluxes compensate each other and net short-wave radiation dominates the SEB. Albedo is central in controlling the melting. Consequently solid precipitation occurrence manages the annual mass balance variability. In the outer tropics, the annual melting is directly related to the annual distribution of precipitation, the period December–February being crucial. However, in the inner tropics, liquid precipitation can occur on the ablation zone, and snowline altitude remains very sensitive to air temperature. Tropical glaciers react rapidly to El Niño events, mainly because of an induced precipitation deficit in the outer tropics and to a temperature increase in the inner tropics, both leading to a rise in snowline altitude."

Berthier, E., Y. Arnaud, D. Baratoux, C. Vincent, and F. Rémy, 2004. Recent rapid thinning of the “Mer de Glace” glacier derived from satellite optical images. Geophys. Res. Lett., 31, L17401, doi:10.1029/2004GL020706, September 3, 2004 PDF


"The rapid wastage of mountain glaciers and their contribution to sea level rise require worldwide monitoring of their mass balance. In this paper, we show that changes in glacier thickness can be accurately measured from satellite images. We use SPOT image pairs to build Digital Elevation Models (DEMs) of the Mont Blanc area (French Alps) for different years. To register the DEMs, we adjust their longitude, latitude and altitude over motionless areas. The uncertainty of the thickness change measurement is greatly reduced by averaging over areas covering altitude intervals of 50 m. Comparisons with topographic profiles and a differential DEM from aerial photographs obtained on the Mer de Glace indicate an overall accuracy of 1 m for the thickness change measurement. Below 2100 m, satellite DEMs show an evolution of the thinning rate from 1 ± 0.4 m.a-1 (years 1979–1994) to 4.1 ± 1.7 m.a-1 (2000–2003)."

Francou, Bernard, Mathias Vuille, Vincent Favier, and Bolivar Cáceres, 2004. New evidence for an ENSO impact on low-latitude glaciers: Antizana 15, Andes of Ecuador, 0°28'S. J. Geophys. Res. – Atm., 109, D18106, doi:10.1029/2003JD004484, September 17, 2004 PDF


"Continuous monthly mass balance measurements from the ablation zone of Antizana 15 glacier in the Andes of Ecuador between January 1995 and December 2002 indicate a strong dependence on El Niño–Southern Oscillation (ENSO). Over the 8-year period investigated, mass balance was negative all year round during El Niño periods but remained close to equilibrium (positive anomalies) during La Niña events. On seasonal timescales, mean ablation rates remain at a quite constant level all year round, but interannual variability shows much larger changes from year to year during the key periods February–May and September. This variability is caused by large differences that occur in the seasonal cycle during the two opposite phases of ENSO. Since ENSO is phase locked to the seasonal cycle with largest sea surface temperature anomalies around boreal winter, November–February, and the atmospheric response to ENSO is delayed by 3 months over the Ecuadorian Andes, year-to-year variations in mass balance are largest between February and May. Energy balance studies at the glacier surface indicate that high air temperature, which favors rain over snowfall, weak and sporadic snowfall, insufficient to maintain a high glacier albedo, low wind speeds, which limit the transfer of energy from melting to sublimation, and reduced cloud cover, which increases the incoming short wave radiation, are the dominant factors related to El Niño, which tend to increase ablation. La Niña events on the other hand are characterized by colder temperatures, higher snowfall amounts, and to a lesser degree, more constant winds, factors which increase albedo and sublimation and therefore preclude melting at the glacier surface. The effects of ENSO variability are also important over the accumulation area, which represents up to 80% of the glacier surface during La Niña events (1999–2000) and 45–60% in El Niño years. Since the accumulation rates increase during these cold periods, the specific net balance and the dynamics of the entire glacier are strongly affected. Longer mass balance records than this 8-year period are needed for conclusive answers about the dependence of the Ecuadorian glaciers on ENSO variability, but initial results suggest that the response observed on Antizana glaciers is very similar to what has been observed previously during ENSO periods on Andean glaciers in the outer tropics. The seasonal dependence on ENSO and the physical mechanisms linking ENSO with mass balance variations on Antizana, however, are different from the response observed on Andean glaciers in the outer tropics."

Paul, Frank, A. Kääb, M. Maisch, T. Kellenberger, and W. Haeberli, 2004. Rapid disintegration of Alpine glaciers observed with satellite data. Geophys. Res. Lett., 31, L21402, doi:10.1029/2004GL020816, November 12, 2004 PDF


"Analyses of multispectral satellite data indicate accelerated glacier decline around the globe since the 1980s. By using digitized glacier outlines inferred from the 1973 inventory and Landsat Thematic Mapper (TM) satellite data from 1985 to 1999, we obtained area changes of about 930 Alpine glaciers. The 18% area reduction as observed for the period 1985 to 1999 (-1.3% a-1) corresponds to a seven times higher loss rate compared to the 1850–1973 decadal mean. Extrapolation of area change rates and cumulative mass balances to all Alpine glaciers yields a corresponding volume loss of about 25 km3 since 1973. Highly individual and non-uniform changes in glacier geometry (disintegration) indicate a massive down-wasting rather than a dynamic response to a changed climate. Our results imply stronger ongoing glacier retreat than assumed so far and a probable further enhancement of glacier disintegration by positive feedbacks."

Joughin, Ian, Waleed Abdalati and Mark Fahnestock, 2004. Large fluctuations in speed on Greenland's Jakobshavn Isbræ glacier. Nature Vol. 432, No 7017, pp. 608-610, December 2, 2004 PDF

"It is important to understand recent changes in the velocity of Greenland glaciers because the mass balance of the Greenland Ice Sheet is partly determined by the flow rates of these outlets. Jakobshavn Isbræ is Greenland's largest outlet glacier, draining about 6.5 per cent of the ice-sheet area, and it has been surveyed repeatedly since 1991 (ref. 2). Here we use remote sensing data to measure the velocity of Jakobshavn Isbræ between 1992 and 2003. We detect large variability of the velocity over time, including a slowing down from 6,700 m yr-1 in 1985 to 5,700 m yr-1 in 1992, and a subsequent speeding up to 9,400 m yr-1 by 2000 and 12,600 m yr-1 in 2003. These changes are consistent with earlier evidence for thickening of the glacier in the early 1990s and rapid thinning thereafter. Our observations indicate that fast-flowing glaciers can significantly alter ice discharge at sub-decadal timescales, with at least a potential to respond rapidly to a changing climate."

Matthews, John A. et al., 2005. Holocene glacier history of Bjørnbreen and climatic reconstruction in central Jotunheimen, Norway, based on proximal glaciofluvial stream-bank mires. Quaternary Science Reviews Vol. 24, No 1-2, pp. 67-90, January 2005 PDF


"Holocene variations of Bjørnbreen, Smørstabbtinden massif, west-central Jotunheimen are reconstructed from the lithostratigraphy of two alpine
stream-bank mires flooded episodically by meltwater. The approach uses multiple sedimentological indicators (weight loss-on-ignition, mean grain size, grain-size fractions, bulk density, moisture content and magnetic susceptibility), an a priori model of overbank deposition of suspended glaciofluvial sediments, a detailed chronology based on 56 radiocarbon dates, and a Little Ice Age sedimentological analogue. Rapid, late-Preboreal deglaciation was indicated by immigration of Betula pubescens by 9700 cal. BP. An interval of at least 3000 years in the early Holocene when glaciers were absent was interrupted by two abrupt episodes of glacier expansion around the time of the Finse Event, the first at ca 8270-7900 cal. BP (Bjørnbreen I Event) and the second at ca 7770 7540 cal. BP (Bjørnbreen II Event). Neoglaciation began shortly before ca 5730 cal. BP with gradualbuild-up to the maximum of the Bjørnbreen III Event at ca 4420 cal. BP.Later maxima occurred at ca 2750 cal. BP (Bjørnbreen IV Event) and at 1300,1260, 1060 and 790 cal. BP (all within the Bjørnbreen V Event). Glaciers were smaller than today and possibly melted away on several occasions in the late Holocene (ca 3950, 1410 and 750 cal. BP). Minor maxima also occurred at ca 660 and 540 cal. BP, within the late Mediaeval Warm Period and the early Little Ice Age, respectively. The Little Ice Age maximum was dated to 213±25 BP (ca 205 cal. BP). The relative magnitudes of the main glacier maxima were determined: Erdalen Event>Little Ice Age Event (Bjørnbreen VI)>Bjørnbreen I (Finse Event) ? Bjørnbreen II>Bjørnbreen VBjørnbreen IV>Bjørnbreen III. These episodic events of varying magnitude and abruptness were used in conjunction with an independent summer-temperature proxy to reconstruct variations in equilibrium-line altitude (ELA) and a Holocene record of
winter precipitation. Since the Preboreal, ELA varied within a range of about 390 m, and winter precipitation ranged between 40 and 160% of modern
values. Winter precipitation variations appear to have been the main cause of these century- to millennial-scale Holocene glacier variations."


Subject: Rocky Mountain News Article (fwd)


FOR CLASS Tuesday April 26th

Hi AT 786

The Rocky Mountain News published the news article noted below. We will discuss Tuesday, as the subject is central to our class. I have also provided information from several e-mails that were sent regarding this article, as additional information. Dallas-please post this under the date of Tuesday's class.


Roger A. Pielke, Sr., Professor and State Climatologist
1371 Campus Delivery, Department Atmospheric Science,
Colorado State University, Fort Collins, CO 80523-1371,
Phone: 970-491-8293/Fax: 970-491-3314, Email:


On Sat, 12 Mar 2005, toms wrote:

Date: Sat, 12 Mar 2005 21:24:45 -0700
From: toms <>

To: "Erickson, Jim" < Roger Pielke <>

Cc: Tom Stohlgren <>

Subject: RE: climate change in colorado

Roger, I'm so sorry that Fred chose to attack you (and climate science that I don't think Fred understands as a plant ecologist), rather than being more
honest about the GCM's. Jim, for the record, I'm siding with Roger (and many are beginning to see the weaknesses of our ability to predict anything 100 years out -- with acceptable uncertainty.

cheers, tom

===== Original Message From Roger Pielke <> =====

Hi Again Jim-

I wanted to add several more comments. First, the NRC report identified climate forcings which are not included in the GCM models that were used in the US National Assessment (or IPCC) reports. Thus the model results that they used to create regional assessments should not have been presented as predictions (the term "projection" is used but this has been interpreted to be the same as predictions; as shown, for example, by the use of years in such presentations (such as 2050-2059)). There has been no validation of the GCM climate change models' prediction skill on the regional scale for the last several decades. Skillful reconstruction of regional climate change over this time period is a prerequisite (a necessary but not sufficient condition) for skillful regional predictions in the future. Even on the global scale, as we have shown in a peer-reviewed scientific paper, the GCM models used in the US National Assessment even failed to skillfully predict the evolution of the global averaged tropospheric temperatures over the last several decades. Finally, I have published in the peer reviewed literature on the use of climate models. Our work has focused on process studies, since we have found that skillful regional and global predictions in response to human climate forcings and natural climate forcings and feedbacks decades into the future is not possible, at present (and may never be). I challenge Fred Wagner to provide original studies that he has authored on the skill of GCM climate change predictions. I hope these added comments are useful for you.

With Best Regards

Roger --

On Fri, 11 Mar 2005, Erickson, Jim wrote:

Date: Fri, 11 Mar 2005 16:12:38 -0700
From: "Erickson, Jim" <>
To: Roger Pielke <>
Subject: RE: climate change in colorado

-----Original Message-----
From: Roger Pielke []
Sent: Friday, March 11, 2005 4:09 PM
To: Erickson, Jim
Cc: Dallas Staley; Tom Stohlgren
Subject: RE: climate change in colorado

Hi Jim

I am on travel for a week and a half with limited e-mail access. As a brief comment, I recommend reading the new National of Academy report on expanding the definition of climate forcings, of which I was a member. I have copied this e-mail to my office who can provide you a link to that report. I was also invited to write an article for the IGBP Newsletter last Fall, which I will also have forwarded to you. The American Association of State Climatologist policy statement also provides a view that disagrees with Wagner. Thus my perspective has a wider acceptance than indicated below.

The most obvious response to his statement is why is he not addressing the science issues I have given?

Finally, I have copied to Dr. Tom Stohlgren, who co-chaired a regional climate assessment with Wagner. I recommend you contact him for more background.


Subject: Today's article

Hi AT 786

Here is an e-mail that I sent as a follow up to the news article.

Roger P.


---------- Forwarded message ----------
Date: Wed, 20 Apr 2005 19:51:07 -0600 (MDT)
From: Roger Pielke <>
To: "Erickson, Jim" <>
Subject: Today's article

Hi Jim

I read your article in the Rocky Mountain News. The statement about the Ouija board is not mine (it implies this from the way the statement on the Ouija board leads into the next paragraph where you specifically quote me).

The GCMs are valuable tools to understand climate processes. My issue is with respect to their use to claim skillful predictions decades into the future. I have published papers using GCMs for process studies, as well as documented their failure to skillfully predict the response of even the global climate over the last few decades. Process studies and prediction studies are two distinctly different uses of these models.

The reference to "one prominent critic once compared general circulation models to Ouija boards" does not accurately represent my perspective on the strengths and weaknesses of the GCMs. I have never made such a statement with respect to GCMs. Who was this individual?

With Best Regards


Roger A. Pielke, Sr., Professor and State Climatologist
1371 Campus Delivery, Department Atmospheric Science,
Colorado State University, Fort Collins, CO 80523-1371,
Phone: 970-491-8293/Fax: 970-491-3314, Email:

Forwarded message ----------
Date: Tue, 26 Apr 2005 09:28:20 -0600
From: "Erickson, Jim" <>
To: Roger Pielke <>
Subject: RE: Today's article

Prof. Pielke,

It was MIT's Richard Lindzen, as reported in the book "The Change in the Weather," by New York Times science reporter William K. Stevens (page 215).

Jim Erickson


Subject: re: Melting or growing glaciers

Hi AT 786

Here is a paper on glaciers, which we will discuss briefly on Tuesday.

Haeberli, W., 2003: Glaciers and ice caps: Historical background and strategies of world-wide monitoring. In: Mass Balance of the Cryosphere: Observations and Modeling of Contemporary and Future Changes, J.L. Bamber and A.J. Payne, Eds., Cambridge University Press, 559-578. PDF



Subject: class

Hi AT 786

Sheri- thanks for an excellent presentation today! Dallas will post when you send to her.

As a reminder, there will be no class on May 3rd. We will meet Tuesday at 10am May 10th for our last class. There will be several presentations; please send Dallas the title if you have not already done so.

Roger P.


Subject: Earth's Energy Imbalance

Hi Class

FYI - just one comment; his statement on the ocean heat imbalance is at variance to what we came up with in class from the Willis et al paper. However, please bring it up in class May 10th if you can reproduce his value.


Roger A. Pielke, Sr., Professor and State Climatologist
1371 Campus Delivery, Department Atmospheric Science,
Colorado State University, Fort Collins, CO 80523-1371,
Phone: 970-491-8293/Fax: 970-491-3314, Email:


---------- Forwarded message ----------
Date: Thu, 28 Apr 2005 20:21:56 -0400
From: James Hansen <>
Subject: Earth's Energy Imbalance

To be removed from Hansen's e-mail distribution list, respond to sender with "Remove" as the subject.

The attached commentary was written to try to avoid misquotes re our article that appeared in Science Express today. (paper) PDF (release) PDF

Note that we have nothing to do with the poll appearing on MSNBC

MSNBC <> as we assiduously avoid politics.


Subject: more ocean heat budget info



Bryden, Harry L., Elaine L. McDonagh, and Brian A. King, 2003. Changes in Ocean Water Mass Properties: Oscillations or Trends? Science Vol. 300, No. 5628, pp. 2086-2088, June 27, 2003 PDF

"A new transindian hydrographic section across 32°S reveals that thermocline mode waters have become saltier and colder since 1987. This change almost entirely reverses the observed freshening of mode waters from the 1960s to 1987 that has been interpreted to be the result of anthropogenic climate change on the basis of coupled climate models. Here, we compare five hydrographic sections from 1936, 1965, 1987, 1995, and 2002 to show that upper thermocline waters (10°C to 17°C) changed little from 1936 to 1965, freshened from 1965 to 1987, and since 1987 have become saltier. These results demonstrate substantial oscillations in mode-water properties."

About deep ocean mixing the following study is revealing:

Naveira, Alberto C. et al., 2004. Widespread Intense Turbulent Mixing in the Southern Ocean. Science Vol. 303, No 5655, pp. 210-213, January 9, 2004 PDF

"Observations of internal wave velocity fluctuations show that enhanced turbulent mixing over rough topography in the Southern Ocean is remarkably intense and widespread. Mixing rates exceeding background values by a factor of 10 to 1000 are common above complex bathymetry over a distance of 2000 to 3000 kilometers at depths greater than 500 to 1000 meters. This suggests that turbulent mixing in the Southern Ocean may contribute crucially to driving the upward transport of water closing the ocean's meridional overturning circulation, and thus needs to be represented in numerical simulations of the global ocean circulation and the spreading of biogeochemical tracers."

Subject: [Fwd: NRC Review of Draft Temperature Trends Report]

Hi Class

Three very informative talks today; thanks!

As promised, here is the draft CCSP report. PDF

It was released by the NRC May 3rd. My minority report and powerpoint talk on it will follow in the next e-mail.

National Research Council, 2005: Review of the U.S. Climate Change Science Program's Synthesis and Assessment Product on Temperature Trends in the Lower Atmosphere. Committee to Review the U.S. Climate Change Science Program's Synthesis and Assessment Product on Temperature Trends in the Lower Atmosphere, Climate Research Committee, Board on Atmospheric Sciences and Climate, Division on Earth and Life Studies, The National Academies Press, Washington, D.C., 74 pp., PDF

Pielke Sr., Roger A., 2005: Minority Report, Comments Provided to the NRC Review Committee of the U.S. Climate Change Science Program's Synthesis and Assessment Product on Temperature Trends in the Lower Atmosphere. Atmospheric Science Bluebook No. 758, Colorado State University, Fort Collins, CO 80523, 8 pp. PDF

See Also: Pielke, R.A. Sr., 2005: Minority Report. Presented to the NRC Review Committee of the U.S. Climate Change Science Program Report entitled “Temperature Trends in the Lower Atmosphere:Understanding and Reconciling Differences” , Chicago, IL, February 23, 2005. PDF 

Roger P.

Subject: Last class presentation

Hi Class,

On Wed May 18th at 11 am, Jana Heisler will give two talks. Lets plan to meet in our classroom, if you are able to attend.

Roger P.




1. Ocean Heat Content Change

2. Arctic Sea Ice Trends

3. Antarctic Sea Ice Trends

4. Northern Hemisphere Snow-Cover Trends

5. Southern Hemisphere Snow-Cover Trends

  • Foster, J.L., A.T.C. Change, D.K. Hall, and R. Kelly, 2001: Seasonal snow extent and snow mass in South America using SSMI passive microwave data. Polar Geography, 25, 41-53

6. Surface Temperature

  • 2004 Was Fourth-Warmest Year Ever Recorded: (submitted by Jacob Jawson)
  • 2005 Could Be Warmest Year Recorded: (submitted by Jacob Jawson)
  • Comiso, J.C., 2003: Warming trends in the Arctic from clear sky satellite observations. J. Climate, 16, 3498-3510. PDF
  • Davey, C.A., and R.A. Pielke Sr., 2005: Microclimate exposures of surface-based weather stations - implications for the assessment of long-term temperature trends. Bull. Amer. Meteor. Soc., in press. PDF
  • deLaat, A.T.J., and A.N. Maurellis, 2004: Industrial CO2 emissions as a proxy for anthropogenic influence on lower tropospheric temperature trends. Geophys. Res. Letts., 31, L05204, doi:10.1029/2003GL019024. PDF
  • Douglass, D.H., B.D. Pearson, S.F. Singer, P.C. Knappenberger, and P.J. Michaels, 2004: Disparity of tropospheric and surface temperature trends: New evidence. Geophys. Res. Letts., 31, L13207, doi:10.1029/2004GL020212. PDF
  • McKitrick, R., and P.J. Michaels, 2004: A test of corrections for extraneous signals in gridded surface temperature data. Climate Res., 26, 159-173. PDF
  • Peterson, T.C., 2003: Assessment of urban versus rural in situ surface temperatures in the contiguous United States: No difference found. J. Climate, 16, 2941-2959. PDF
  • Pielke, R.A. Sr., C. Davey, and J. Morgan, 2004: Assessing "global warming" with surface heat content. Eos, 85, No. 21, 210-211. PDF
  • Station photographs from the presentations at the Regional Climate Change Workshop for South and Central Asia.Pune, India, 14-19 Feb. 2005, by Tom Peterson, NCDC/NOAA PDF
  • Volney, C.F., 1804. The view of the climate and soil of the United States of America. C. Mercier and Co., London. PDF
  • Zhou, L., R.E. Dickinson, Y. Tian, J. Fang, Q. Li, R.K. Kaufmann, C.J. Tucker, and R.B. Myneni, 2004: Evidence for a significant urbanization effect on climate in China. PNAS. 101, 9540-9544, PDF

7. Surface Evaporation

  • Roderick, M.L., and G.D. Farquhar, 2004: Changes in Australian pan evaporation from 1970 to 2004. Int. J. of Climatol., 24, 1077-1090. PDF

8. Arctic Snow

  • Foster, J.L., 1989: The significance of the date of snow disappearance on the Arctic tundra as a possible indicator of climate change. Arctic and Alpine Research, 21, 60-70.
  • Foster, J.L., J.W. Winchester, E.G. Dutton, 1992: The date of snow disappearance on the Arctic tundra as determined from satellite, meteorological station and radiometric in situ observations. IEEE Transactions on Geoscience and Remote Sensing. 30, 793-798. PDF

9. SST

10. General Climate Change News

11. Tropospheric Temperature Trends

  • Chase, T.N., R.A. Pielke, J.A. Knaff, T.G.F. Kittel, and J.L. Eastman, 2000: A comparison of regional trends in 1979-1997 depth-averaged tropospheric temperatures. Int. J. Climatology, 20, 503-518. PDF
  • Chase, T.N., B. Herman, R.A. Pielke Sr., X. Zeng, and M. Leuthold, 2002: A proposed mechanism for the regulation of minimum midtropospheric temperatures in the Arctic. J. Geophys. Res., 107(D14), 10.10291/2001JD001425. PDF
  • Hegerl, G.C., and J.M. Wallace. 2002: Influence of patterns of climate variability on the difference between satellite and surface temperature trends. J. Climate, 15, 2412-2428. PDF
  • Hurrell, J.W., S.J. Brown, K.E. Trenberth, and J.R. Christy. 2000: Comparison of tropospheric temperatures from radiosondes and satellites: 1979-98. Bull. Amer. Meteor. Soc., 81, 2165-2177. PDF
  • Pielke, R.A., J. Eastman, T.N. Chase, J. Knaff, and T.G.F. Kittel, 1998: 1973-1996 trends in depth-averaged tropospheric temperature. J. Geophys. Res., 103, 16927-16933.PDF
  • Pielke, R. A., J. Eastman, T.N. Chase, J. Knaff, and T.G.F. Kittel, 1998: Correction to ``1973-1996 trends in depth-averaged tropospheric temperature''. J. Geophys. Res., 103, 28909-28911. PDF
  • Pielke, R.A. Sr., T.N. Chase, T.G.F. Kittel, J. Knaff, and J. Eastman, 2001: Analysis of 200 mbar zonal wind for the period 1958-1997. J. Geophys. Res., 106, D21, 27287-27290. PDF
  • Pielke Sr., R.A., and T.N. Chase, 2004: Technical Comment: "Contributions of anthropogenic and natural forcing to recent tropopause height changes". Science, 303, 1771b. PDF
  • Santer, B.D., M.F. Wehner, T.M.L. Wigley, and R. Sausen, 2004: Technical Comment: "Response to Comment on "Contributions of anthropogenic and natural forcing to recent tropopause height changes.'' Science, 303, 1771c. PDF

  • Pielke, Sr., R.A., T.N. Chase, with input from J. Christy, and T. Reale, 2004: Scientific Comment on R-278 and R-278a. PDF

  • Gaffen et al. 2000: Multidecadal changes in the vertical temperature structure of the tropical troposphere. Nature, 287, 1242-1245. PDF (submitted by T. Matsui)
  • Santer et al. 2000: Interpreting differential temperature trends at the surface and in the lower troposphere. Nature, 287, 1227-1232. PDF (submitted by T. Matsui)
  • Vinnikov and Grody, 2003: Global warming trend of mean tropospheric temperature observed by satellites. Nature, 302, 269-272. PDF (submitted by T. Matsui)
  • (submitted byToshi Matsui)
  • (submitted by Khishig)

12. Land-use/Land-cover

13. Model Simulations of Climate Change

  • Koch, D., and J. Hansen, 2005: Distant origins of Arctic black carbon: A Goddard Institute for Space Studies ModelE experiment. J. Geophys. Res., 110, D04204, doi10.1029/2004JD005296. PDF

14. Glaciers and Ice Sheets

  • (submitted by Phil Klotzbach)
  • See the 2 Emails from Wednesday, April 20th for full text - papers from that email are listed below

    • Oerlemans, Johannes Hans, 2005. Extracting a Climate Signal from 169 Glacier Records. Science Express published online before print March 3, 2005

      • ABSTRACT: A temperature history for different parts of the world has been constructed from 169 glacier length records. Using a first-order theory of glacier dynamics, changes in glacier length were related to changes in temperature. The derived temperature histories are fully independent of proxy and instrumental data used in earlier reconstructions. Moderate global warming started in the middle of the 19th century. The reconstructed warming in the first half of the 20th century is 0.5 K. This warming was remarkably coherent over the globe. The warming signals from glaciers at low and high elevations appear to be very similar.


    • Seidel, Dian J. and Melissa Free, 2003. Comparison of Lower-Tropospheric Temperature Climatologies and Trends at Low and High Elevation Radiosonde Sites. Climatic Change Vol. 59, No 1-2, pp. 53-74, July 2003 PDF
    • Favier, Vincent, Patrick Wagnon, and Pierre Ribstein, 2004. Glaciers of the outer and inner tropics: A different behaviour but a common response to climatic forcing. Geophys. Res. Lett., 31, L16403, doi:10.1029/2004GL020654, August 27, 2004 PDF
    • Berthier, E., Y. Arnaud, D. Baratoux, C. Vincent, and F. Rémy, 2004. Recent rapid thinning of the “Mer de Glace” glacier derived from satellite optical images. Geophys. Res. Lett., 31, L17401, doi:10.1029/2004GL020706, September 3, 2004 PDF
    • Francou, Bernard, Mathias Vuille, Vincent Favier, and Bolivar Cáceres, 2004. New evidence for an ENSO impact on low-latitude glaciers: Antizana 15, Andes of Ecuador, 0°28'S. J. Geophys. Res. – Atm., 109, D18106, doi:10.1029/2003JD004484, September 17, 2004 PDF
    • Paul, Frank, A. Kääb, M. Maisch, T. Kellenberger, and W. Haeberli, 2004. Rapid disintegration of Alpine glaciers observed with satellite data. Geophys. Res. Lett., 31, L21402, doi:10.1029/2004GL020816, November 12, 2004 PDF
    • Joughin, Ian, Waleed Abdalati and Mark Fahnestock, 2004. Large fluctuations in speed on Greenland's Jakobshavn Isbræ glacier. Nature Vol. 432, No 7017, pp. 608-610, December 2, 2004 PDF
    • Matthews, John A. et al., 2005. Holocene glacier history of Bjørnbreen and climatic reconstruction in central Jotunheimen, Norway, based on proximal glaciofluvial stream-bank mires. Quaternary Science Reviews Vol. 24, No 1-2, pp. 67-90, January 2005 PDF
  • Haeberli, W., 2003: Glaciers and ice caps: Historical background and strategies of world-wide monitoring. In: Mass Balance of the Cryosphere: Observations and Modeling of Contemporary and Future Changes, J.L. Bamber and A.J. Payne, Eds., Cambridge University Press, 559-578. PDF
  • Pederson, G.T., D.B. Fagre, S.T. Gray, and L.J. Graumlich, 2004: Decadal-scale climate drivers for glacial dynamics in Glacier National Park, Montana, USA. Geophys. Res. Letts., 31, L12203, doi:10.1029/2004GL019770, 2004. PDF

15. GCM Simulations of Solar Irradiance

  • Kiehl, J.T., and Kevin E. Trenberth, 1997. Earth's Annual Global Mean Energy Budget. BAMS Vol. 78, No 2, 197-208. PDF
  • Potter, Gerald L., and Robert D. Cess, 2004. Testing the impact of clouds on the radiation budgets of 19 atmospheric general circulation models, J. Geophys. Res., 109, D02106, doi:10.1029/2003JD004018, January 27, 2004. PDF

16. Global Precipitation Trends

  • Lixin Lu, March 28, 2005: Introduction to Vegetation Index Data Set (NDVI) Available from AVHRR, MODIS, and SPOT. View the Presentation PDF
  • Phil Klotzbach, April 12, 2005: Northeast United States Snowfall (1974-2003). View the Presentation PDF
  • Kirsten Koehler, April 12, 2005Discussion on Mahowald and Luo and Mahowald and Kiehl. View the Presentation PDF
  • Sheri Conner Gausepohl, April 26, 2005, Analysis of Monthly Precipitation Data from the GPCP Project from 1982 - 2002 PDF


  • Jacob Jawson: "Land-Use Change and Forestry in Germany" 
  • Phil Klotzbach: "Global Tropical Cyclone Frequency and Intensity Change (1972-2003)" PDF
  • Toshi Matsui: "Satellite-Based Assessment of the Aerosol Indirect Effect" PDF
  • Jana Heisler, Wednesday, May 18th, 11 a.m. "Changing Precipitation Regimes and Terrestrial Ecosystems"
Research Group: