Estimation of Surface Insolation

Abstract

The incoming solar radiation from the sun (insolation) that reaches the Earth's surface (about 50% of that emitted from the sun) determines the exchange of energy between the land and the atmosphere and consequently, controls climate and climate change. Environmental satellites are considered useful tools for providing information on surface radiative fluxes at various temporal and spatial scales, improving estimation of terrestrial water and energy storage. For several years now, observations from satellites have been used to obtain information on the various components of atmospheric and surface radiative fluxes, initially, retrospectively, and more recently, operationally. In this paper, discussed are the needs for information on radiative fluxes in hydrological applications, methodologies for obtaining such information by methods of remote sensing, accuracy of such estimates, and current status of data availability. Examples of applications in hydrological studies and climate research are provided, and links to international activities and future prospects are indicated.