ATMOSPHERIC IMPLICATIONS OF STUDIES OF CENTRAL AMERICAN VOLCANIC ERUPTION CLOUDS

During February 1978, 11 sampling flights were made in Guatemala through the eruption clouds from the volcanoes Pacaya, Fuego and Santiguito. Measurements were made of SO42-, SO2, HCl, HF, and 11 cations that were in water-soluble form, on samples collected by a specially designed filter pack. Particle size distributions were obtained and the particles were identified. Since most of the the sulfur was found to be in the form of SO2, the H2SO4 droplets resulting from major explosive eruptions must largely result from the reaction of SO2 with OH, at the same time depleting the atmosphere of OH. Each volcano was emitting 300-1500 metric tons of SO2 per day.- from Authors