Abstract:
Numerical modeling of permafrost dynamics is crucial to understanding permafrost vulnerability and ecosystem resilience in response to climate change in high-latitude regions. Permafrost modeling with NASA’s Catchment Land Surface Model (CLSM) has demonstrated generally increasing regional Active Layer Thickness (ALT) in Alaska in recent decades owing to rising air temperatures. By comparing CLSM-simulated ALT against in-situ observations and airborne radar retrievals from the AirMOSS flight campaigns we demonstrate here that the model captures the spatial variability of ALT across different soil types and local climates. Furthermore, we discuss the impacts of soil organic carbon, soil moisture, snow and land cover on long-term, underground thermodynamic processes associated with permafrost degradation. Finally, we use the modeling results to estimate the permafrost degradation rate and identify the regions where permafrost is most susceptible to thawing.