The Earth Radiation Budget Experiment /ERBE/ - An overview

An overview of the Earth Radiation Budget Experiment (ERBE) is presented along with a brief history relative to the evolution of the ERBE science measurement requirements. A description of the ERBE instrument is presented which includes both the nonscanner and scanner instrument packages. In addition, ERBE science investigations are summarized. The ERBE, to be flown on a three-satellite mission in the 1980s will, for the first time, provide radiation measurements with sufficient spatial and temporal resolution to determine the monthly average radiation budget on regional, zonal, and global scales and the diurnal variation on regional and monthly scales. HE observation of the Earth from the moon has produced a vivid impression of how little contact other bodies in the solar system have with the Earth, except for the light from the sun. This image is perhaps the culmination of a scientific perception developed over the past two centuries in which the most significant interchange between the Earth and the surrounding universe arises through electromagnetic radiation. The details of this interchange have been the subject of an enormous body of research. Indeed, one of the first revisions of our knowledge of this interchange resulted from radiation budget measurements obtained from Earth- orbiting satellites over the last 20 yrs which indicated that the Earth was substantially darker and warmer than had been thought previously.M2 The relationship between these measurements and the Earth's temperature, which is thought to be related to climate changes, is quite complex. A better understanding of this relationship will require more accurate radiation measurements such as those that will be obtained by ERBE. The ERBE will be launched on three United States satellites in the 1980s and will provide measurements with sufficient spatial and temporal resolution to determine the Earth's radiation budget on regional, zonal, and global scales over monthly, seasonal, and yearly time periods. The ERBE design will provide for the acquisition of more accurate radiation budget data than have been obtained in the past, and this will enable us to better understand climate and determine its predictability. The management of the ERBE is the responsibility of the NASA Langley Research Center (LaRC). The LaRC is responsible for the instrument procurement and development and the initial scientific use of the resulting measurements. ERBE science will be implemented through an 18-member science team which was selected through an "Announcement of Opportunity." The team will provide recommendations about design features which will be incorporated into the instrument design and which will enhance the understanding of the radiation measurements. They will guide the for- mulation of algorithms for processing the ERBE measurements into validated data products for science in- vestigations. In addition, the science team will conduct the initial measurement validation and scientific investigations to demonstrate the quality, scope, and utility of the ERBE data set over the next several years.