Satellite-based remote sensing offers the best opportunity for studying the properties of atmospheric aerosols and their radiative effects on the global scale over extended periods Tropospheric aerosols represent the largest uncertainty in predicting the radiative forcing of climate (IPCC, 2001). A key question is whether atmospheric aerosols contribute to warming or cool the climate system. Since the sign of direct radiative forcing is controlled by the ability of aerosol particles to absorb light, the information on the single scattering albedo of different aerosol types and its variations with aerosol lifecycles is clearly very desirable. Furthermore, the wavelength-dependent values of single scattering albedo from the UV to IR are important in retrieving aerosol optical depth from satellites passive remote sensing and for climate modeling. We describe the design of a space-borne polarimeter that was derived from the key science requirements. The performance of this candidate polarimeter, operating in the UV/VIS/NIR spectral regions, is described. The optical design form and various optical performance parameters, including transmittance calculations of the polarimeter’s spectral channels showing the “leakage” of polarization states, as well as the degree of polarization as function of wavelength and field of view are presented for the various wavelength regions. An overview of the instrument performance and driving operational parameters is presented.
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