Multi-decadal variability of sudden stratospheric warmings in an AOGCM

作者：Schimanke S^*; Koerper J; Spangehl T; Cubasch U

来源：Geophysical Research Letters, 2011, 38: L01801.

DOI：10.1029/2010GL045756

The variability in the number of major sudden stratospheric warmings (SSWs) is analyzed in a multi-century simulation under constant forcing using a stratosphere resolving atmosphere-ocean general circulation model. A wavelet-analysis of the SSW time series identifies significantly enhanced power at a period of 52 years. The coherency of this signal with tropospheric and oceanic parameters is investigated. The strongest coherence is found with the North Atlantic ocean-atmosphere heat-flux from November to January. Here, an enhanced heat-flux from the ocean into the atmosphere is related to an increase in the number of SSWs. Furthermore, a correlation is found with Eurasian snow cover in October and the number of blockings in October/November. These results suggest that the multi-decadal variability is generated within the ocean-troposphere- stratosphere system. A two-way interaction of the North Atlantic and the atmosphere buffers and amplifies stratospheric anomalies, leading to a coupled multi-decadal mode. Citation: Schimanke, S., J. Korper, T. Spangehl, and U. Cubasch (2011), Multi-decadal variability of sudden stratospheric warmings in an AOGCM, Geophys. Res. Lett., 38, L01801, doi:10.1029/2010GL045756.

• 出版日期2011-1-4