Authors
Mark C. Serreze (NSIDC), Jessica Voveris (Air Force Weather)
Abstract
Arctic rain-on-snow (ROS) events can have significant impacts on Arctic wildlife and socioeconomic systems. This study addresses the meteorology of Arctic ROS events from two case studies, with comparisons with other known significant cases. The first event, occurring near Nuuk, Greenland, generated significant impacts, including slush avalanches. The second, less severe, event occurred within the community of Iqaluit, Nunavut. Atmospheric blocking played a leading role in ROS initiation for these and other events, with atmospheric rivers - narrow bands of high water vapor transport, typically originating from the tropics and subtropics - having both direct and indirect effects. Cyclone induced low-level jets and resultant 'warm noses' of higher air temperatures and moisture transport are other key features in ROS generation. To our knowledge, our study is the first to visualize how the varying strength and manifestation of these coupled features contribute to differences in the severity of Arctic ROS events. The meteorological drivers identified here find support from other studies on Arctic ROS events and are similar to weather features associated with Arctic precipitation events of extreme magnitude.