MODELED SAHARAN DESERT DUST RADIATIVE EFFECTS OVER THE IBERIAN PENINSULA AND ATLANTIC OCEAN
Resumen
Since atmospheric aerosols may provoke important modifications in the Earth radiation budget, these particles play a major role in the global climate system. The aerosol effects are usually classified as: direct, connected to the scattering and absorption of radiation; semi-direct connected with absorbing aerosols that may be responsible for cloud evaporation; and indirect, due to the influence of aerosols on cloud microphysical properties and lifetime. The difference in net radiative flux at a specific level in the atmosphere, with and without aerosols, defines the so-called aerosol radiative forcing. Precise estimation of its magnitude gives crucial contributions for the assessment of the Earth’s radiation budget. However, the magnitude of aerosol radiative forcing and its contribution to global warming is still subject to considerable uncertainty (IPCC, 2007). Aerosols can have either positive or negative contributions to atmospheric radiative forcing, depending on their properties (Liao and Seinfeld, 1998; Kaufman et al., 2002, Santos et al. 2008).Citas
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