Yukon River Watershed: Northern Watershed Change
Rena Bryan1, Robert Busey2, William Bolton3, Larry Hinzman4
1University of Alaska Fairbanks, PO Box 757340, Fairbanks, AK, 99775, USA, Phone 907-474-1556, rbryan [at] iarc [dot] uaf [dot] edu
2University of Alaska Fairbanks, PO Box 757340, Fairbanks, AK, 99775, USA, rcbusey [at] alaska [dot] edu
3University of Alaska Fairbanks, PO Box 757340, Fairbanks, AK, 99775, USA, bbolton [at] iarc [dot] uaf [dot] edu
4University of Alaska Fairbanks, PO Box 757340, Fairbanks, AK, 99775, USA, lhinzman [at] iarc [dot] uaf [dot] edu
Changes in the terrestrial hydrologic cycle in northern watersheds can be seen through permafrost warming. We simulate present and future modeled permafrost temperatures in the Yukon River Watershed through known and projected air temperature data and information on the collection of buffers between the atmosphere and the cryosphere: the active layer, snow and vegetation. Our modeling methods combine a meteorological model with a permafrost temperature model in 1km resolution in the 847,642km Yukon River Watershed. The MicroMet model is a quasi-physically based model used to spatially interpolate irregularly spaced point meteorological data. We call on 1997–2007 data from 104 Integrated Surface Data meteorological stations and 100 grid points in the ECHAM5 A1B 2090–2100 projection. The Temperature at the Top of the Permafrost (TTOP) model is a numerical model for estimating the thermal state of permafrost. TTOP relates more readily available near surface temperatures to temperatures at the depth of seasonal variation using user-defined snow and landcover n-factors (to relate air temperature to soil surface temperature) and soil thermal conductivities (to simulate the propagation of heat through the active layer). We compare the present and future thermal stability of permafrost in the Yukon River Watershed to make light of vulnerable areas for changes to lake and wetland size and distribution.