Numerical Modeling of Spatial Permafrost Dynamics in Alaska

The Geophysical Institute Permafrost Laboratory model (GIPL) simulates soil temperature dynamics and the depth of seasonal freezing and thawing by solving 1D non-linear heat equations with phase change numerically. In this model the process of soil freezing/thawing is occurring in accordance with the unfrozen water content curve and soil thermal properties, which are specific for each soil layer and for each geographical location. At the present stage of development, the GIPL 2.0 model is combined with ArcGIS to facilitate preparation of input parameters and visualization of simulated results in the form of digital maps. The future climate scenario was derived from the Massachusetts Institute of Technology MIT-2D climate model output for the 21st century. This climate scenario was used as a driving force in the GIPL model. Initial results of calculations show that by the end of the current century widespread permafrost degradation could begin everywhere in Alaska southward from the Brooks Range.