Climate model simulations of the effects of the El Chichon eruption.

An energy balance climate model is used to calculate the effect of the 4 April 1982 eruption of the El Chichon volcano on surface air temperature for the next 10yr. The maximum cooling of 1.0-1.4^oC occurs at the North Pole in the spring and fall of 1984 and 1985. The Northern Hemisphere annual average response is largest in 1984 and 1985 with a cooling of 0.4-0.5^oC. The separate land and ocean responses as functions of latitude and time of year are shown. The particular patterns that result are caused by the snow-albedo and ice-thermal intertia feedbacks. These results have important implications for the detection of CO₂-induced climate change. -Author