Hypersensitive decadal oscillations in the Arctic/subarctic climate

Abstract

A conceptual model of the Arctic climate system is generated by taking two key components in the coupled atmosphere-ice-ocean system, having a basis on a box model with water exchanges among the Arctic Basin, the Greenland-Iceland-Norwegian (GIN) Seas and the North Atlantic. One of the key components is deep water formation in the GIN Seas induced by the saline Atlantic inflow to the area. The second key component is a positive feedback between a more intense (or weaker) Polar Vortex and less (or more) ice cover in the Arctic Basin. The system possesses a decadal oscillation in a limited range of the combination of the key component intensities. This oscillatory state is potentially relevant to the decadal oscillations remarkable in the Arctic climate only for last three decades. The present study promotes an attempt to examine responses of the Arctic atmospheric circulation to decadal variability in the surface heat flux, as these responses are the most uncertain.