The role of microphysical and chemical processes in prolonging the climate forcing of the Toba Eruption

摘要: The mega-eruption of Toba, Sumatra, occurred around 73 Ka ago, during the onset a glaciation Late Quaternary. This coincidence combined with unprecedented amount sulphur released by this volcano has led to hypothesis that Toba sulphate aerosols caused transient surface cooling which may have contributed shift climate system. Because self limiting effect gravitational sedimentation, climatic impact extremely large injections into stratosphere are thought be rather limited. Here we present model calculations combining microphysical and chemical feedbacks show eruption could instead formation long-lasting volcanic aerosol layer. Although concentrations radiatively active species such as O3 or SO2 also been considerably perturbed, resulting forcings should only slightly moderated first few years following eruption. According our results, high stratospheric loading lead more prolonged on than previously assumed.