LIAM COLGAN
I received my BScH in Biology and Geography from Queen's University in Kingston, Ontario, Canada in 2004 and my MSc in Earth and Atmospheric Sciences, under the supervision of Dr Martin Sharp, from the University of Alberta in Edmonton, Alberta, Canada in 2007. I am currently a PhD candidate in Geography at the University of Colorado under the supervision of Dr Konrad Steffen. I am also a past co-chair of the Canadian Youth Steering Committee (CYSC) for the International Polar Year (IPY).
CIRES, University of Colorado,
216 UCB, Boulder, Colorado,
80309-0216, USA
+1 303 492 6881
william.colgan@colorado.edu
PhD RESEARCH
The main causes of sea level rise, which has increased from 1.5 mm a-1 over the past century to 3.1 mm a-1 over the past decade, are believed to be the thermal expansion of water and increased inputs from melting glaciers (Cazenave and Nerem, 2004). Currently, a significant discrepancy exists between the estimated sum of thermal expansion and freshwater input, and observed sea level rise (Cazenave and Nerem, 2004). This discrepancy provides a strong impetus to improve the quantification of the glacier melt contribution to sea level rise. The Greenland Ice Sheet (GIS), if melted completely, would raise global sea level by 6.7 m (Steffen and Box, 2001). The mass balance of the GIS is influenced by both surface mass balance and ice dynamics. The GIS outlet glaciers, conduits of enhanced flow which drain into the sea, are important controls in the movement of land-based ice into the sea. Previous research has suggested that these low elevation outlet glaciers may be susceptible to increased future flow velocities due to increased basal lubrication as a result of increased surface meltwater reaching the bed (Zwally et al., 2002). Improved understanding of the influence of increased meltwater production on the ice dynamics of the GIS is of interest in the modeling sea level rise scenarios.
The drainage basin around Swiss Camp, Greenland (69.5 °N, 49.2 °W) provides an ideal study site to investigate the influence of meltwater on ice dynamics, as a large dataset of field measurements has been collected in the vicinity since 1990 by the Program for Arctic Regional Climate Assessment (Thomas et al., 2003). My PhD project involves collecting primary field data and combining it with previously published data to constrain a high spatial (1x1 Km) and temporal (daily time-step) resolution model of ice sheet dynamics coupled with glacial hydrology (supra-, en- and sub-) in the Swiss Camp basin during the 2007 to 2009 melt years. An important and novel aspect of this project will be parameterizing the (basal) flow that can be attributed to subglacial hydrological conditions. To accomplish this, the current configuration of flow regimes in the Swiss Camp basin will be delineated (Burgess et al., 2001), and the conditions necessary for varying degrees of basal flow, such as ice thickness, elevation, or bed topography, will be elucidated from the distribution of basal and enhanced basal flow regimes.
The Arctic is predicted to experience a regional + 3.7 °C warming by 2100 (ACIA, 2005). The second phase of my PhD project involves investigating the sensitivity of the Swiss Camp basin ice dynamics to projected future warming. The validated Swiss Camp basin model will be run to an anticipated millennial-scale equilibrium solution using a 1 year time-step, at multiple fixed temperature climatic boundary conditions to control surface mass balance and meltwater production. Comparing the ice outflow from Swiss Camp basin at multiple temperatures / meltwater production levels, should allow a temperature-ice outflow relation to be elucidated for the basin. The results of this basin-scale investigation can be realistically extrapolated to the GIS-scale.
PUBLICATIONS
- W. Colgan, J. Davis and M. Sharp. 2008. Is the high-elevation region of Devon Ice Cap thickening? Journal of Glaciology. 54(186), 428-436. ( 07J042.pdf)
- W. Colgan and M. Sharp. 2008. Combined oceanic and atmospheric influences on net accumulation on the Devon Island Ice Cap, Nunavut, Canada. Journal of Glaciology. 54(184), 28-40. (07J044.pdf)
PRESENTATIONS
- W. Colgan and M. Sharp. 2006. "Investigating oceanic and atmospheric controls on snow accumulation on the Devon Ice Cap using ice cores and gridded moisture soruce probability values." Circumpolar Students Association. Edmonton, Alberta, Canada.
- M. Sharp, W. Colgan, E. Doxsey-Whitfield, L. Hryciw, L. Nicholson and I. Koch. 2005. "A shallow ice core network for the Eastern Arctic." ArcticNet Annual Scientific Meeting. Banff, Alberta, Canada.
- W. Colgan and M. Sharp. 2004. "Recent inter-annual variability in accumulation and snow snowmelt, Prince of Wales Icefield, Ellesmere Island, Nunavut." 35th International Arctic Workshop. Edmonton, Alberta, Canada.
POSTERS
- W. Colgan and M. Sharp. 2006. "Combined oceanic and atmospheric influences on net accumulation on the Devon Island Ice Cap, Nunavut, Canada." ArcticNet Annual Scientific Meeting. Victoria, British Columbia, Canada. (1.5 Mb -.jpg)
- L. Nicholson, M. Sharp, D. Fisher, C. Kinnard, J. Zheng, B. Mogge and W. Colgan. 2006. "1000 year climate proxies from Prince of Wales Icefield, Ellesmere Island, Nunavut." ArcticNet Annual Scientific Meeting. Victoria, British Columbia, Canada. (14.2 Mb -.pdf)
- W. Colgan, M. Sharp and L. Hryciw. 2005. "Inter-annual variability in net accumulation reconstructed from three firn cores from the Devon Island Ice Cap, Nunavut." ArcticNet Annual Scientific Meeting. Banff, Alberta, Canada. (1.5 Mb -.jpg)
- L. Nicholson, I. Koch, W. Colgan, E. Doxsey-Whitfield, M. Sharp and C. Zdanowicz. 2005. "High-resolution ice core records from the Prince of Wales Icefield, Ellesmere Island." ArcticNet Annual Scientific Meeting. Banff, Alberta, Canada. (1.5 Mb -.jpg)
- M. Sharp, W. Colgan and E. Doxsey-Whitfield. 2004. "Recent inter-annual variability in accumulation and snow snowmelt, Prince of Wales Icefield, Ellesmere Island, Nunavut." ArcticNet Annual Scientific Meeting. Quebec City, Quebec, Canada. (1.2 Mb -.jpg)
FIELD PHOTOS
FIELD VIDEOS
STEFFEN GROUP IN THE NEWS
- Percer les secrets de la fonte du Groenland - Le Temps (13 Jun 2008 - avec photos: 1 | 2)
- Planet in Peril: Greenland - CNN (24 Oct 2007)
- Greenland's Ice Sheet Melts as Temperatures Rise - CNN (24 Oct 2007)
- Konrad Steffen: The Global Warming Prophet - Popular Science (3 Jul 2007)
CRYOSPHERE IN THE NEWS
- Ice diary: Science in the fast-changing Arctic - BBC (25 June 2008)
- Scientist: 'We're toast' without action on global warming - CNN (24 Jun 2008)
- Canadians argue for polar bear hunt - The Guardian (24 June 2008)
- Ice Core Reveals How Quickly Climate Can Change - Scientific American (23 Jun 2008)
- Treaty on Ice - New York Times (23 Jun 2008)
- Greenland Ice Shows Rapid Climate Flips, Study Says - National Geographic News (19 Jun 2008)
- Trying to head off an Arctic 'gold rush' - BBC (29 May 2008)
- Arctic declaration denounced as territorial 'carve up' - The Guardian (29 May 2008)
- Closed-door Arctic deal denounced as 'carve-up' - The Guardian (28 May 2008)
- How the ice breaks too early in the land of the rising sun - The Guardian (28 May 2008)
- Canada to reaffirm sovereignty over High Arctic waters at conference - CBC (27 May 2008)
- Greenland's disappearing lakes leave giant ice sheets largely unmoved - The Guardian (18 Apr 2008)
- Dan Rather Reports: A Crack in the Ice - HDNet (20 Oct 2007)
- The Big Melt - CBC (24 Sep 2007)
- Melting Ice Cap Triggering Earthquakes - The Guardian (8 Sep 2007)
- Analysis Finds Large Antarctic Area Has Melted - New York Times (16 May 2007)
- The Warming of Greenland - New York Times (16 Jan 2007)
LINKS
- Arctic Circle - Established in 1947, this group meets monthly to hear interesting and informative presentations on a wide range of Arctic topics.
- ArcticNet - A Canadian network that brings together scientists and managers, and their partners, in the natural, human health and social sciences to study the impacts of climate change in the coastal Canadian Arctic.
- ArcticStat - A public and independent statistical database dealing with the countries, regions and populations of the Circumpolar Arctic.
- Canadian Council for Geographic Education - A joint initiative of The Royal Canadian Geographical Society and the National Geographic Society which has marked the IPY by developing a set of free bilingual lesson plans on Canada's North for elementary, intermediate and secondary schools.
- Climate and Cryosphere Project (CliC) - A branch of the World Climate Research Programme that stimulates, supports, and coordinates research into the processes by which the cryosphere interacts with the rest of the climate system.
- David Suzuki Foundation - A foundation which uses science and education to promote solutions that conserve nature and help achieve sustainability within a generation.
- Global Land Ice Measurements from Space (GLIMS) - A project designed to monitor the world's glaciers using data from optical satellite instruments.
- International Association for Impact Assessment (IAIA) - An organization for advancing practices in impact assessment, in which sound science and full public participation provide a foundation for equitable and sustainable development.
- International Glaciology Society (IGS) - An organization that stimulates interest and encourages research into the scientific and technical problems of snow and ice.
- International Polar Year (IPY) - A large scientific programme focused on the Arctic and the Antarctic from March 2007 to March 2009.
- NASA Satellite Tracking - A site containing several interfaces for the real-time viewing and the forecasting of ground tracks of over 900 satellites.
- Rapidfire - A realtime portal (and archive) of low-resolution images from the MODIS Terra and Aqua satellites.
- Scientific Committee on Antarctic Research (SCAR) - A committee of the International Council for Science (ICSU) that is charged with the initiation, promotion and co-ordination of scientific research in Antarctica.
- Social Economy Research Network of Northern Canada - A research project to provide an inventory of Social Economy organizations in northern Canada.
- Straight Up North - A communication tool for those interested in northern Canadian communities, environments and making research address northern interests and needs.
