Abstract
Recent model calculations have suggested that the occurrence of ENSO (El Niño/Southern Oscillation) events may be related to the appearance of a stratospheric aerosol generated by volcanic eruptions. The association of sea surface temperature anomalies in the eastern tropical Pacific Ocean with the occurrence of major eruptions in investigated over the period 1866–1982. It is found that after the eruption of low latitude volcanoes (95 per cent confidence level). These results are consistent with the statistical dynamical model calculations of MacCracken and Luther (1984) for the El Chichon aerosol. A second unexpected result was that the sea surfaces temperatures are significantly cooler than normal nine to fifteen months after the eruption of a high latitude volcano (>20°). Additional data such asin situmeasurements in the stratosphere and acid concentrations in the Greenland ice core are discussed to support the observed association.