On the Storms Passing Over Southern Baffin Island During Autumn 2005

Abstract

Although strong storms affect all regions of the Arctic, little research has focused on the details of their structure and evolution—particularly of the storms passing over southern Baffin Island. Such storms form in a variety of locations and often occlude before passing over the region. To study these storms, a field project was conducted at Iqaluit, Nunavut, in the eastern Canadian Arctic in the autumn of 2005. We launched rawinsondes into six storm systems and made detailed measurements that included ice crystal structure and snow accumulation. The storms had quite different histories: some produced strong winds; some produced snow, while others produced rain and freezing precipitation; and three led to record-breaking temperatures. The types of precipitation particles varied greatly, but aggregates and rimed particles dominated. When comparing the six storms, we found numerous similarities between the surface and the vertical atmospheric conditions, but there were also distinct differences.