Department of Environmental Science and Engineering, California Institute of Technology, Pasadena, USA

now at: Atmospheric, Oceanic and Planetary Physics, University of Oxford, UK

Department of Environmental Science and Engineering, California Institute of Technology, Pasadena, USA

Department of Chemical Engineering, California Institute of Technology, Pasadena, USA

Aerosols, Clouds, and Climate, Max Planck Institute of Meteorology, Hamburg, Germany

Met Office Hadley Centre for Climate Change, Exeter, UK