Dr. Michelle Walvoord is a Research Hydrologist with the United States Geological Survey鈥檚 Earth System Processes Division in Lakewood, Colorado. She holds a B.A. in Geology from Hamilton College and M.S. in Hydrology & Ph.D. in Earth Sciences from New Mexico Tech. Throughout her career, Dr. Walvoord has focused on non-isothermal multiphase flow and transport in subsurface environments with a geographic range that stretches from the arid southwestern US to boreal Alaska. Her research relies on a blend of field, statistical, and process-based modeling approaches at multiple spatial and temporal scales to address coupled hydrologic and biogeochemical responses to climate and other perturbations including wildfire. Dr. Walvoord currently serves as an Associate Editor for Water Resources Research. She serves on graduate student committees at Colorado School of Mines, Universit茅 Laval, and University of Colorado, 麻豆影院.
Abstract
Observing and Modeling the Expansion of Lateral Talik Development in Permafrost Landscapes
Studies spanning arctic and boreal permafrost regions provide observations and physically-based models describing the deepening of the seasonal active layer in response to climate change. A growing number of data and model-based studies document the development of perennial thaw zones, or supra-permafrost taliks, below the depths of seasonal ice as the next stage of top-down permafrost thaw evolution. Discerning the presence and movement of water (or lack thereof) in these actively thawing zones and determining hydraulic connectivity between surface water bodies initiated by talik development are critical; these characteristics affect biogeochemical cycling and the lateral transport of dissolved constituents, including organic carbon, released from permafrost. This presentation highlights recent field and modeling efforts aimed at constraining baselines and future projections of talik distribution. These examples provide context for discussing implications of talik development and permafrost thaw acceleration in a variety of geologic settings.