Sean A. Twomey

Sean Andrew Twomey ( ; 1927–2012) was an Irish professor of atmospheric physics who made contributions to remote sensing, cloud physics and inversion mathematics. The Twomey effect, the mechanism by which aerosols can increase the albedo of clouds and cool the climate, is named after him.

Sean Twomey's 1974 paper 'Pollution and the planetary albedo' was one of two papers to be awarded the 2004 Haagen-Smit Prize by the editors of the journal Atmospheric Environment.

Career In the 1950s, Twomey conducted research in aerosol microphysics at the Commonwealth Scientific and Industrial Research Organisation (CSIRO) in Australia. In 1959 he moved to the United States, working first at the National Oceanic and Atmospheric Administration, then from 1963 at the Naval Research Laboratory, during which time he developed the constrained linear inversion method for determining aerosol size distributions from measurements.

In 1976, Twomey was appointed professor at the University of Arizona's Department of Atmospheric Physics, a position he held until his retirement in 1990.