Carbon Dioxide and Methane Flux in a Dynamic Arctic Tundra Landscape: Decadal‐Scale Impacts of Ice Wedge Degradation and Stabilization
Kimberly P. Wickland, M. Torre Jorgenson, Joshua C. Koch, Mikhail Kanevskiy, Robert G. Striegl
Abstract
Abstract Ice wedge degradation is a widespread occurrence across the circumpolar Arctic causing extreme spatial heterogeneity in water distribution, vegetation, and energy balance across landscapes. These heterogeneities influence carbon dioxide (CO 2 ) and methane (CH 4 ) fluxes, yet there is little understanding of how they effect change in landscape‐level carbon (C) gas flux over time. We measured CO 2 and CH 4 fluxes in an area undergoing ice wedge degradation near Prudhoe Bay, Alaska, and combined with repeat imagery analysis to estimate seasonal landscape‐level C flux response to geomorphic change. Net CO 2 and CH 4 emissions changed by −25% and +42%, respectively, resulting in a 14% increase in seasonal CO 2 ‐C equivalent emissions over 69 years as ice wedge degradation formed water‐filled troughs. The dynamic ice wedge degradation/stabilization process can cause significant changes in CO 2 and CH 4 fluxes over time, and the integration of this process is important to forecasting landscape‐level C fluxes in permafrost regions abundant in ice wedges.