Possible association of stratospheric aerosols and El Nino type events

To determine whether the 1982/83 El Nino event and the eruption of El Chichon in April 1982 are related, eleven similar eruptions at low latitudes (<20°, tropical) between 1868 and 1980 were analyzed for subsequent warm sea surface temperature anomalies in the eastern tropical Pacific Ocean. The composite result using superposed epoch analysis show a significant warming of the sea surface temperatures in the region 0°‐10°S, 90° ‐180°W. The results are also consistent with the statistical dynamical model calculations of MacCracken and Luther which indicate atmospheric circulation changes similar to those thought to lead to an El Nino type event within a few seasons after the establishment of an El Chichon type aerosol. In addition the composite behavior of twenty eruptions at high latitudes (extratropical, >20°) show just the opposite behavior. They show significant cooling of the sea surface temperatures in this region especially in the fourth and fifth season after the eruption. The association is found to be significant at the 95% level.