GLOBAL LAND SURVEYS FROM LANDSAT OBSERVATIONS: PAST PRESENT AND FUTURE

摘要

Land cover is a critical component of the Earth system, influencing land-atmosphere interactions, greenhouse gas fluxes, ecosystem health, and availability of food, fiber, and energy for human populations. Despite 35 years of Landsat observations, there has not been a unified global analysis of land-cover trends nor has there been a global assessment of land-cover change at Landsat-like resolution. Following the Global Land Surveys (GLS) 1975,1990 and 2000, NASA and USGS jointly support development of GLS-2005 and -2010 -- global 30-m spatial resolution data sets based mostly on Landsat data. The GLS-2000, -2005 and the new GLS-2010, which is under development, represent a system of global land datasets for monitoring changes on a 5-year interval, paving the way toward continuous global land-cover monitoring at Landsat-like resolution in the next decade. The ultimate goal is to develop an ongoing, routine, moderate-resolution global record of land-cover changes.