Global and regional land cover characterization from satellite data: an introduction to the Special Issue

During the 1980s, pioneering research to map and monitor land cover at cont inental scales using data acquired by the Advanced Very High Resolution Rad iometer laid the foundation for the derivation of global and regional land cover products in the 1990s. This Special Issue highlights some of the achi evements in the 1990s and indicates challenges and opportunities in the com ing decade. The confluence of several factors creates the opportunity for m ajor advancements in routine identification of land cover and land cover ch ange from satellite data. These factors include: (1) the recognition of the need for land cover information to meet both scientific and policy objecti ves; (2) improved measurements from a suite of new sensors with greatly imp roved spatial and spectral resolutions and processing algorithms for atmosp heric and other corrections; and (3) the availability of high performance c omputing resources and improved data analysis tools. These factors, along w ith an established pattern of international collaboration, will allow us to build on the last two decades' research leading toward operational systems for characterizing land cover from satellite data.