Saudi Arabian solar radiation network and data for validating satellite remote sensing systems

Abstract

The National Aeronautics and Space Administration (NASA) will be launching complex satellite remote-sensing platforms for monitoring the earth's radiation budget, land use, and atmospheric physics for periods exceeding 10 years. These Earth Observing Satellite (EOS) platforms will strive to detect man-made and natural variations in the Earth's climate. Form 1993 to the present (1999), the National Renewable Energy Laboratory and the King Abdulaziz City for Science and Technology (KACST) in Riyadh, Saudi Arabia, conducted a joint solar radiation resource assessment project to upgrade the solar resources assessment capability of the Kingdom of Saudi Arabia. KACST has deployed a high quality 12-station network in Saudi Arabia for monitoring solar total horizontal, direct beam, and diffuse radiation. One- and five-minute network data is collected and assessed for quality. 80 percent or more of the network data fall within quality limits of +/- 5 percent for correct partitioning between the three radiation components. This network will provide measured data for validating the NASA remote sensing systems. We describe the network, quality assessment procedures, and the result of estimating aerosol optical depth and precipitable water vapor. These are important for validating satellite estimates of radiation fluxes in and at the top of the Earth's atmosphere.