In earlier positions, he has worked at the NOAA/ARL Atmospheric Turbulence and Diffusion Division in Oak Ridge,Tennessee; at Argonne National Laboratory in Illinois; and at the Commonwealth Scientific and Industrial Research Organization (Division of Atmospheric Physics) in Aspendale,Victoria Australia.
Dans le cadre de postes occupés précédemment, il a travaillé à la Division de la turbulence et de la diffusion atmosphériques de la NOAA/ARL à Oak Ridge (Tennessee); au Argonne National Laboratory en Illinois; et à la Commonwealth Scientific and Industrial Research Organization (Division of Atmospheric Physics) à Aspendale (Victoria) en Australie.