Dr. Alex D Crawford
Visiting Assistant Professor
Geology Department | The College of Wooster, Ohio
Abstract:
The Arctic Frontal Zone (AFZ) is a narrow band of strong horizontal temperature gradients along the Arctic coastline. It develops each summer in response to differential heating of the atmosphere by adjacent land and ocean/ice surfaces in summer. This feature, which only exists in summer, has long been thought to contribute to summer cyclogenesis in the Arctic. However, only with the broad spatial extent and fine temporal resolution of modern atmospheric reanalyses has it become possible to closely assess that theory. The research presented here finds little evidence of the AFZ as a storm generator; rather, it appears to act as an intensifier of mature storms that originally form at lower latitudes. Results from the Community Earth System Model (CESM) Large Ensemble demonstrate that under a strong warming scenario, the AFZ remains a cyclone intensifier, and changes to the AFZ are largely restricted to June. The AFZ develops earlier in the year and appears stronger in June. This does not lead to appreciable changes in Arctic Ocean storm activity, however, because the storms entering the AFZ become weaker. Therefore, the strengthening of the AFZ acts to offset weakening of mid-latitude storm tracks in a warming world.