Carbon-Water Cycle Modeling

The Arctic warming observed in recent decades has amplified changes in terrestrial ecohydrological processes. A number of process-based models have been developed to simulate the ecohydrological processes in cold regions under changing climate conditions. These models have simulated prominent changes in ecohydrological processes in regions of eastern Siberia at point and watershed scales, such as degrading permafrost, decreasing snow extent, and increasing river discharge and evapotranspiration induced by warming; model results have been consistent with observations. These modeling results improve our understanding of the responses of ecohydrological processes to the warming climate, in turn contributing to further model improvement and better projection of future changes in hydrologic processes. However, model representations of some cold region hydrological processes remain insufficient and need further improvement. This chapter summarizes changes in key processes and ecohydrology conditions of the Lena watershed based on a synthesis of observations and model simulations.