Abstract

Many different components of the Arctic environment (e.g. sea ice conditions, P-­E, river discharge, atmospheric temperatures etc.), are changing rapidly in response to the warming climate, and are all likely to have a significant impact on the dynamics of the Arctic Ocean.

In the first part of the talk I will discuss how these changes are affecting the accumulation of freshwater within the Beaufort Gyre. Recent observations show that the region has accumulated 8000 km3 of freshwater since the 1990s, and there is evidence that the accumulation may have accelerated since the early 2000s. Using a simple process model we find that this acceleration is associated with an enhancement in the efficiency of momentum transfer into the upper ocean, which is being driven by the decline in Arctic sea ice cover.

In the second part of  the talk I’ll discuss how increasing internal wave activity due to the declining sea ice cover, may enhance the magnitude of the heat flux from the Atlantic Water to the underside of the sea ice. There is sufficient heat contained within the Atlantic Water to melt all sea ice within the Arctic Ocean, however, it is isolated from the surface by the cold halocline. Using a 1D model we investigate how much more heat may be brought to the surface as the increasing internal wave activity destabilises the halocline, resulting in a larger diffusive heat flux and allowing heat to be directly entrained into the surface mixed layer.