Science Update: Stratospheric aerosols from the Sarychev volcano eruption in the 2009 Arctic summer

An ACP article by F. J├ęgou and co-authors investigates the emissions released into the stratosphere by the Sarychev volcano, on the Kuril Islands, northeast of Japan. The strongest sulphur dioxide emissions occurred from 15-16 April 2009 and an estimated 0.9Tg were injected into the UTLS. By the first week of July the aerosol plume had spread over much of the Arctic region, and was measured by several satellites (OSIRIS, CALIOP), at the surface (lidar), as well as by balloon-borne instruments during the STAC campaign. The OSIRIS stratospheric aerosol optical depth observations indicate an enhancement at 750nm of a factor of 6, with a value of 0.02 in late July compared to 0.0035 before the eruption. Model simulations of the eruption using the HadGEM2 and MIMOSA models agree well with the satellite, in situ, and ground-based observations. Aerosol concentrations returned to near-background levels by spring 2010. The full abstract can be found here.