Decadal windstorm activity in the North Atlantic-European sector and its relationship to the meridional overturning circulation in an ensemble of simulations with a coupled climate model

Research output: Contribution to journalArticlepeer-review

Authors

Colleges, School and Institutes

External organisations

  • School of Geography, Earth and Environmental Sciences, University of Birmingham
  • Institute for Meteorology, Freie Universität Berlin
  • Model Development Group, EQECAT

Abstract

The relationship between decadal variations in the North Atlantic meridional overturning circulation (MOC) and North Atlantic/Western European windstorm activity during the extended winter season is studied. According to an ensemble of three 240-year long simulations performed with the ECHAM5-MPIOM model, periods of high decadal windstorm activity frequently occur in the years following a phase of weak MOC (i.e. when the MOC starts to recover). These periods are characterised by a distinctive pattern in the mixed layer ocean heat content (OHC). A positive anomaly is located in the region 45°N-52°N/35°W-16°W (west of France). Negative anomalies are located to the North and South. The signal can be detected both in the heat content of the oceanic mixed layer and in the sea surface temperatures. Its structure is consistent with anomalously enhanced baroclinic instability in the region with the strong negative OHC gradient (30°W-10°W/45°N-60°N), which eventually produces a higher probability of windstorms.

Details

Original languageEnglish
Pages (from-to)1545-1555
Number of pages11
JournalClimate Dynamics
Volume43
Issue number5-6
Publication statusPublished - 1 Jan 2014

Keywords

  • Decadal variability, MOC, Windstorms

ASJC Scopus subject areas