Stratospheric aerosol optical depths, 1850–1990

A global stratospheric aerosol database employed for climate simulations is described. For the period 1883–1990, aerosol optical depths are estimated from optical extinction data, whose quality increases with time over that period. For the period 1850–1882, aerosol optical depths are more crudely estimated from volcanological evidence for the volume of ejecta from major known volcanoes. The data set is available over Internet.