Variability and Trends of Global Atmospheric Frontal Activity and Links with Large-Scale Modes of Variability

Abstract

Presented here is a global analysis of frontal activity variability derived from ERA-Interim data over the 34-yr period of January 1979-March 2013 using a state-of-the-art frontal tracking scheme. In December- February over that epoch, there is a northward shift of frontal activity in the Pacific in the NorthernHemisphere (NH). In the Southern Hemisphere (SH), the largest trends are identified in the austral summer and are manifested by a southward shift of frontal activity over the Southern Ocean. Variability of frontal behavior is found to be closely related to the main modes of atmospheric circulation, such as the North Atlantic Oscillation (NAO) for the Atlantic-European sector in the NH..