Quantifying the changes in the radiative properties of marine stratocumulus due to different factors

The radiative properties of marine stratocumulus, which affect the global climate, are influenced by a number of factors including aerosols, the temperature profile, the presence of drizzle, the surface heat flux and the entrainment of warm dry air from above the cloud layer. As part of VOCALS-UK we are investigating the effects of these different factors on the small scale structure and microphysics of marine stratocumulus, and hence on its radiative properties, by using the Met Office Large Eddy Model. The model simulations are validated against measurements from the BAe-146 research aircraft obtained during the VOCALS field campaign, over the southeast Pacific in October and November 2008, and the relative contributions of the different factors are then analyzed by using the 'factorial' method of Teller and Levin.