Developing a Global-Scale Environmental Land Data Set from Satellite Data

The international earth science community has recognized the value of global-scale environmental land data sets derived from satellite data. The scientific requirements specify the development of a 1-km AVHRR data set of the entire global land surface to meet the needs of major global change research initiatives, land cover mapping, environmental monitoring, and climate and ecosystem modelers. The strategy for acquisition of satellite observations of the global land area includes development of partnerships with academic and government agencies in the United States and foreign countries. An international network of over thirty AVHRR ground receiving stations has acquired over 150,000 daily AVHRR observation of the global land surface since Apri1 1 , 1992. Under the guidance of NASA and the International Geosphere Biosphere Programme, processing standards for the AVHRR data have been developed for calibration, atmospheric correction, geometric registration, and the production of global 10-day maximum normalized difference vegetation index (NOVI) composites. The major uses of the composites are related to the study of surface vegetation cover. The data processing system for production of the global data set includes high-speed computers, near-line mass storage, and specialized software for data processing and production management. The technology for distributing the large data volume of a global-scale 1- km data set to an international science community has been developed using a world wide web interface. The AVHRR data and 10-day composites are archived and distributed by the United States Geological Survey, EROS Data Center, the National Oceanic and Atmospheric Administration, and the European Space Agency