Effect of volcanoes on the vertical temperature profile in radiosonde data

Abstract

Comparison of the responses of radiosonde temperatures to aerosol forcing from the Agung, El Chichon, and Pinatubo volcanic eruptions shows the expected stratospheric warming, with a maximum at 50 mbar in the tropics, and a predominantly cooling effect in the troposphere with a maximum in the middle or upper troposphere. The tropospheric cooling is greater after the Pinatubo eruption, with a significant effect on the temperature difference between the upper and lower tropical troposphere. The tropospheric coolings after El Chichon and Agung are more vertically uniform. The size of the difference between the Pinatubo and El Chichon responses is somewhat sensitive to the choice of data subset and the index used to account for the effects of El Niño-Southern Oscillation. Differential effects of volcanic eruptions on the upper and lower tropical troposphere should be considered as possible causes of differential temperature trends at those levels.