On the interannual variability of Alaskan climate in a regional climate system model

Long-term simulations with the Arctic Regional Climate System Model (ARCSyM) are conducted over Arctic Alaska to investigate climate interannual variability and its trend. This study focuses on the impact of biosphere-atmosphere interaction on modulating the interannual variability. The role of changing plant phenology in climate variation is dicscussed. The results are compared with available observations and simulations from global GCMs to highlight the uncertainty in high-latitute climate simulations. It is found that simulated climate interanual variability has close connection with interannual variation of the physical characteristics of vegetation prescribed in the model. Temperature and evaporation are most sensitive variables to the interannual variation of vegetation.