Cooperative Institute for Research in Environmental Sciences

Abstracts: 3

The Arctic Frontal Zone: Analysis, Observation and Modeling

Amanda Lynch, Mark Serreze, Jason Beringer, Terry Chapin, Martyn Clark, Ian McHugh, Andrew Slater, Nigel Tapper

Conceptual models of the global general circulation typically have not included a separate high latitude frontal zone. The notion of a region of frequent mesoscale frontal activity in northern high latitudes emerging as distinct from frontal activity in middle latitudes can be traced back to the early work of Dzerdzeevskii [1945]. The Arctic front has been proposed variously to arise from the differential heating between snow-free land and cold Arctic Ocean in summer; from the interactions between these coastal contrasts and orography; and from contrasts in surface heating between the tundra and boreal forest. Conceptually, treeline control of the Arctic front could arise from much larger sensible heat fluxes over the forested area compared with adjacent tundra, deeper and warmer boundary layers and hence the creation of large scale horizontal gradients between surface types which generate synoptic baroclinic zones.

In this poster, we present our work spanning examinations of NCEP/NCAR reanalyses, field observations and regional model simulations to determine the structure and seasonality of the Arctic front and the necessary and sufficient factors dictating the formation of the front.