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West Siberian Lowlands. Role of seasonal flooding on greenhouse gas emissions from Siberian wetlands -Ted Bohn. 30% of world’s wetlands are boreal/arctic High-latitudes currently experiencing pronounced climate change How will greenhouse emissions respond?. Globally, wetlands are
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West Siberian Lowlands Role of seasonal flooding on greenhouse gas emissions from Siberian wetlands -Ted Bohn • 30% of world’s wetlands are boreal/arctic • High-latitudes currently experiencing pronounced climate change • How will greenhouse emissions respond? • Globally, wetlands are • largest natural source of methane • large sink of carbon dioxide / carbon reservoir • Source/sink behavior tied to soil moisture and temperature Until recently, sub-grid variability in surface moisture not considered in large-scale models Lehner and Doll, 2004
Science Questions What are the effects of sub-grid variability in lake-wetland moisture on wetland greenhouse gas fluxes? • How does distributed water table depth affect wetland CH4 emissions and their response to climate change? • How does seasonal flooding and partial saturation affect wetland C balance and its response to climate change? • Can we use a combination of satellite observations and modeling to estimate boreal lake CH4 emissions?
CH4 and CO2 fluxes are correlated in space and time with fractional saturated area • Simulated fluxes and soil C storage match magnitude and spatial distribution of current observations • End-of-century climate likely to be warmer and wetter, leading to: • Doubling of CH4 emissions everywhere • Shift in CO2 sink northward • Southern peatlands become source of CO2