On the Response of Hemispheric Mean Temperature to Stratospheric Dust: An Empirical Approach

Abstract

The cooling effects of stratospheric dust and the corresponding response times for hemispheric mean temperature changes are studied using an empirical approach and a simple time-dependent formulation. The approach couples estimates of stratospheric dust injections by volcanic eruptions to an available record of mean temperature anomalies. The time period examined is 1883?1968. Cooling coefficients (per unit mass of dust) are developed for continued loadings from the transient data; the results are compared to theoretical values developed elsewhere. Response times are also compared. The many uncertainties are noted, as are difficulties introduced by apparent underlying temperature trends. The effort is exploratory in nature, but the overall results are consistent with past arguments that stratospheric dust (as from large volcanic eruptions) is of climatic significance. It is suggested, since climatic changes involve integrals over time, that long-term records of stratospheric dust, as well as other recognized climate-determining parameters, should be established and maintained.