Application of remote sensing to climatic and environmental studies in arid and semi-arid lands

The arid and semi-arid regions of the Earth, collectively termed "drylands", are particularly sensitive to processes of climatic and environmental change. One of the common features of most and environments is a lack of observational data on climate and surface environment. This is less true for semi-arid regions, but even there this continues to be a problem. For this reason, there is relatively little actual data for examining such issues such as climatic change, resource degradation and desertification. Remote sensing offers new ways to assess various climatic and environmental characteristics and to answer questions related to these issues. This paper considers primarily six areas: rainfall; vegetation cover, type and phenology; surface hydrology; radiation and surface albedo; aerosols; and desertification. Select examples are given of remote sensing methodologies and applications in each area and some of the important conclusions that have been drawn about some of these topics on the basis of remote sensing studies