Determination from Space of Atmospheric Total Water Vapor Amounts by Differential Absorption near 940 nm: Theory and Airborne Verification

摘要: Abstract A new technique is proposed to estimate atmospheric total water vapor amounts from space. The consists of viewing the Earth's surface in two spectral channels, one narrow, other wide, centered on same wavelength at absorption maximum near 940 nm. With these characteristics, ratio solar radiance measured channels independent reflectance and yields a direct amount integrated along optical path. To test technique, we designed built two-channel radiometer based above concept. Airborne experiments carried out with device demonstrate technique's feasibility under clear sky conditions over both sea land. Over ocean presence thick aerosol layers, however, may be underestimated by as much 20%. Compared satellite microwave techniques, which are applicable most weather conditions, has adva...