The Effect of Four Major Volcanic Eruptions on Atmospheric Aerosol Loading Based on Satellite Data

Abstract

The aim of this study is to investigate the influence of major volcanic eruptions on atmospheric aerosol loading. Great volcanic eruptions, apart from emitting large amounts of gases, also introduce particulate matter into the Earth’s atmosphere, thus affecting aerosol loadings. Since aerosol optical thickness (AOT) is a good measure of aerosol loading, AOT is used in the present study, with the aim to first identify and secondly to quantify the effect of volcanic eruptions on AOT. This was achieved by comparing AOT values over and around the volcanoes before and after their eruptions. To this aim, geographical distributions of AOT based on MODIS (Moderate Resolution Imaging Spectroradiometer) satellite observations during the periods of volcano eruptions were used. The study focuses on the following four major world volcanic eruptions: (1) Mount Merapi (October 2010), (2) Puyehue-Cordon Caulle (June 2011), (3) Eyjafjallajökull, (March 2010) and (4) Mount Pinatubo (April 1991). The results show that all four volcanic eruptions produced a significant amount of aerosols, increasing significantly the AOT values over the volcanoes and nearby areas for periods ranging from a few weeks to a few months, with the Mount Pinatubo eruption having the greatest impact.