Present and Future Surface Water

This poster presents a technical approach that is being developed to evaluate change in size and distribution of northern lakes and wetlands spatially and temporally under a climate warming scenario. The landscape shifts expected for the future restrain estimates of carbon dioxide and methane flux to the atmosphere and shape considerations of these local and regional measurements in the global budget. A high-resolution temperature model, TopoClimate, references USGS determined topographic features and the National Weather Service weather forecast model, Global Forecast System, to represent synoptically and topographically driven processes at present. For future simulations, TopoClimate references GCM model ECHAM5/MPI-OM under balanced energy sources in an integrated world emissions scenario, A1B, and topography. ECHAM5/MPI-OM best reproduces the present key features of both Alaska and the Arctic observed synoptic climates. A numerical model for estimating the permafrost thermal composition, TTOP, is used to improve the resolution of permafrost extent in the Yukon River Basin. TTOP will reference the TopoClimate temperature map, as well as maps of soil moisture and thermal properties, surface n-factors derived from landcover type, and snow cover. The propagation of surface temperature through soil is numerically modeled by TTOP, using soil properties and microclimatic effects. TTOP has been applied to the Seward Peninsula in estimating past, present, and future permafrost distributions. A physically based, potentiometric surface algorithm will extract steepness and relative elevation from topography. Precipitation inputs are National Climate Data Center meteorological data, distributed by MicroMet and SnowModel, and from ECHAM5/MPI-OM under the A1B scenario for future. Derived hydraulic head will be used to determine local groundwater discharge and recharge areas. Additionally, we plan to reference satellite image classification of wetlands. Hydraulic gradient, analyzed in concert with permafrost distribution provides insight into surface water presence. The approach includes continual change of surface water presence evaluated through time.