Comparison of Stratospheric Warmings Following Agung and Chichon

Abstract

Temperatures at 50, 30, 20 and 10 mb in the western quadrant of the Northern Hemisphere are used to estimate the stratospheric warming resulting from the volcanic eruptions of Agung in 1963 and El Chichon in 1982. After allowing for quasi-biennial temperature variations, a warming of about 4°C is fond at 50 mb in the equatorial zone following Agung, and at 30 mb in the north subtropics following Chichon. In both cases the warming was at a maximum two seasons after the eruption. The Chichon-induced warming in the American sector of the north subtropics is indicated to be slightly greater than in the Pacific sector.