Variations in stratospheric aerosol—arising primarily from sporadic volcanic eruptions—are an important contributor to climate variability. Major volcanic eruptions have led to pronounced decreases in global surface temperature over seasonal-to-decadal timescales. The marked increase in stratospheric aerosol since 2000 has also offset a large part of the anthropogenic greenhouse gas forcing over the same period and contributed substantially to the recent “hiatus” in global warming.
Advancing our understanding of the influence of volcanoes on climate relies upon better knowledge of the radiative forcings of past eruptions and the microphysical, chemical and dynamical processes which affect the evolution of stratospheric aerosol properties. This can only be achieved by combining information from satellite and in-situ observations of recent eruptions, aerosol modelling activities, and reconstructions of past volcanic histories from proxies.
This session seeks presentations from research aimed at better understanding variations in stratospheric aerosol and the associated radiative forcing. A particular focus will be on constraining uncertainties in volcanic forcings over the historical period (1850-present), but studies focussing on longer timescales are encouraged as well.
Contributions on other aspects of the stratospheric aerosol life cycle are also welcome, including observations of aerosol and precursor gases, their transport, and the role of upper troposphere and stratosphere processes.