Publication Date:
2012-02-23
Description:
This study aims to give an overview on Southern Hemisphere (SH) climate effects of tropical volcanic eruptions. Major volcanic eruptions which directly inject high SO2 amounts into the tropical stratosphere have a significant impact on the global climate. Volcanic sulfate aerosol in the stratosphere is transported by the large scale meridional overturning circulation in the stratosphere, called the Brewer-Dobson circulation (BDC). Due to the different
strengths of the BDC in the Northern Hemisphere (NH) and SH, and to its seasonality, we find different climate effects between the two hemispheres. To address the role of the seasonality, and eruption strength, we perform a set of
model simulations with stratospheric SO2 injections of magnitudes corresponding to the Mt. Pinatubo and Los Chocoyos eruptions during January and July. In this study we focus on temperature, precipitation and circulation changes, and contrast the differences between the SH and the NH responses. We particularly address the effects from the stratosphere down to the surface, showing the dominant atmospheric modes during winter: the Southern Annular Mode (SAM) and the Northern Atlantic Oscillation (NAO) for
the SH and NH respectively.
Type:
Conference or Workshop Item
,
NonPeerReviewed
