Date: Tuesday, June 13th, 2023 Time: 11-11:50 AM Mountain Time Location: ZOOM + 372A & B (VizStudio), SEEC, University of Colorado Boulder
Title: Scaling from Plot to Peninsula: High-resolution Vegetation Type Mapping in Alaska Low Arctic Tundra
Abstract: High-resolution maps of vegetation distribution are crucial for studying the impacts of climate change on Arctic tundra ecosystems and their associated feedbacks. Bridging scales and integrating field-scale observations, airborne remote sensing and environmental datasets, this study examines the current distribution and potential future redistribution of vegetation types across the low Arctic region of northwestern Alaska, USA. In a two-step upscaling approach, we first developed a deep neural network-based classifier, trained on field vegetation surveys and airborne hyperspectral imagery, to create high-resolution (5 m) landscape-scale maps of vegetation types with an accuracy exceeding 93%. In the second upscaling step, we used a Random Forest environmental niche model trained on the landscape-scale maps to determine the habitat suitability of vegetation types across the southern Seward Peninsula region, based on topography and climate variables. Using future climate projections from five earth system models (RCP 8.5, CMIP5) as inputs to the niche model, we predict that shrub cover is expected to increase from 32.2-34.5% (mean 33.4%, std dev 0.85%) in 2010-19 to 51.6-75.4% (mean 69.4%, std dev 9.1%) by 2050-59 at the regional scale, particularly along hillslopes and high-resource environments like floodplains and stream corridors, at the expense of other vegetation types. Generation of high-resolution maps of vegetation types for the data-scarce low Arctic tundra region is an important step towards improved parameterization of Arctic land surface models and simulation of Arctic vegetation in Earth system models.
Short speaker bio: Shashi Konduri is a remote sensing scientist at the National Ecological Observatory Network (NEON)/Battelle, Boulder, CO. He is interested in studying the structure, composition, and environmental drivers of vegetation distribution over large spatiotemporal scales using remote sensing data. He has experience working with earth observing data from different sensors (multispectral/hyperspectral/lidar), mounted on various platforms (spaceborne/airborne) and collected across different spatiotemporal scales to study diverse vegetation types (crops/Arctic tundra shrubs/tropical savannas). In collaboration with scientists at reputed government agencies such as NASA, Oak Ridge National Laboratory (ORNL) and the US Forest Service, he has developed and deployed spatiotemporal data mining methods for improved understanding of plant structure and composition and enhanced predictive modeling of vegetation productivity.
NOTICE: THIS EVENT IS CANCELED BECAUSE THE SPEAKER IS SICK.
Observations of Antarctic ice-shelf surface melt and hydrology, and implications for dynamics and break-up with Dr. Alison Banwell, CIRES
About 75% of Antarctica is buttressed by floating ice shelves, which regulate the rate that grounded ice is lost to the ocean. Since the 1990s, many ice shelves have thinned, and in some cases disintegrated. With projected future increases in atmospheric temperatures, models suggest that surface meltwater production will rise non-linearly, and as a result, ice shelves will become more vulnerable to surface meltwater-induced breakup events. Focussing on the north George VI Ice Shelf, Antarctic Peninsula, I will present field and satellite-based observations and model analysis, which reveal insights into the role surface meltwater on ice-shelf dynamics such as flexure and fracture.\
Bio: Alison (Ali) Banwell is a glaciologist and Research Scientist in the Cooperative Institute for Research in Environmental Sciences (CIRES), part of the University of Colorado Boulder. Broadly, her research focuses on monitoring and quantifying glacier, ice-sheet and ice-shelf melt, hydrology and dynamics using satellite remote-sensing, fieldwork and modeling. She received her Ph.D. in Glaciology from the University of Cambridge, and her B.Sc. from the University of Edinburgh, UK. She has led may field expeditions in Antarctica and has also conducted fieldwork on the Greenland Ice Sheet, Svalbard and the Himalaya.
Dr. Dan Feldman (Lawrence Berkeley National Lab), Gijs de Boer (CIRES), and colleagues present on two years of research in the East River Valley. Join us in person in the Sievers Conference Room (SEEC S228).
All CIRES Visiting Fellows and all CIRES Post-docs are invited to join this upcoming Get-Together on June 21 from 3:00 to 5:00 pm at Scott Carpenter Park.
This will be a fun, informal social event and a great opportunity to meet new and friendly faces from across CIRES. Drinks and snacks will be provided! Everyone is welcome, including partners and family members.
Please look for our group on the hill near the playground and the parking lot. We will have some chairs set up. If you need any help with directions, please call 303-735-7104. We hope to see you there!
Please note: In the case of rain, this event will take place indoors instead at Twisted Pine Brewing Co., located at 3201 Walnut St. in Boulder.
Thank you for attending the CIRES Rendezvous last month. Please help us continue to improve this annual science event by taking a moment to fill out this year's survey: https://cuboulder.qualtrics.com/jfe/form/SV_79UrfGNLrfCpGzI, by COB Friday, June 23.