Receding ice cover and Arctic decadal climate variability

The Arctic cyclones occur most frequently over areas of exposed water such as the Nordic Seas where air-sea interactions are vigorous. The high capacity to store and release heat in these regions and their role in ocean exchanges with the Atlantic are also associated with the variability of climate on longer multi-year time-scales. Within the ocean this variability is reflected in changes in the temperature and salinity of near surface water masses. As the Arctic sea ice cover declines in the coming centuries the available heat capacity of the Arctic climate system will increase dramatically. This increase in thermal inertia along with reductions in the oceanic exchange of heat with the Atlantic must impact the strength and time-scales of climate variability. Here we explore these consequences for the hydrography of the Arctic ocean and surface meteorology through examination of ensembles of CMIP5 coupled atmosphere-ocean-sea ice simulations carried out under greenhouse forcing scenarios.