Decadal variability and a recent amplification of the summer Beaufort Sea High

Authors


Abstract

[1] The Beaufort Sea High (BSH), an anti-cyclone over the Beaufort Sea, is an important feature of the summer atmospheric circulation over the Arctic Ocean. For example, years characterized by low Arctic sea ice extent are typically associated with the presence of a stronger BSH; with the opposite occurring during years with high sea ice extent. In this paper, we show that there exists variability on the decadal time scale in the intensity and location of the summer BSH. We also show that there has been a trend towards a stronger summer BSH that began in the late 1990s. This trend is shown to be coincident with a tendency towards a reduction in cyclogenesis during the summer over the Beaufort Sea. We argue that that these trends are the result of a warming of the troposphere in the western Arctic and the concomitant reduction in baroclincity.

Ancillary