Department of Environmental Sciences

Department of Environmental Sciences







Back To:
Seminar Abstracts
Environmental Sciences Seminar Abstract            

  THE REAL AND SIMULATED LIFE OF PHOTONS IN THE WEST AFRICAN SAHEL
Mark Miller
Rutgers University

This seminar will focus on measurements collected in the Sahel region of West Africa and simulations of the region in Global Climate Models (GCMs). The Sahel’s location along the tropical margin, its population density, which is roughly equal to that of the northeastern United States, and its economic status combine to increase its vulnerability to climate change. The region exhibits a complex monsoon circulation driven by north-south temperature and moisture gradients that produce all of its rainfall during a short six- to eight-week wet season. Important drivers of the radiation budget and the hydrological cycle were measured during the year 2006 using the Atmospheric Radiation Measurement (ARM) Mobile Facility (AMF) and the Geostationary Earth Radiation Budget (GERB) satellite. Continuous measurements of the shortwave (SW) and longwave (LW) radiation fluxes at the surface and the top of the atmosphere were supplemented by continuous, detailed measurements of clouds and other radiative influences within the atmospheric column that modulate these boundary fluxes. This collection of measurements enabled the radiative impacts of clouds upon the atmospheric column itself to be explicitly determined. Predictions in four GCMs used in the Intergovernmental Panel for Climate Change fourth Assessment report (IPCC-AR4) are analyzed to determine if these models are able to simulate the observed structure. Particular emphasis is placed upon the manner in which two of the four GCMs simulate the radiative impacts of cloud cover.


Last updated: 10/25/2011