USING MULTISOURCE DATA IN GLOBAL LAND-COVER CHARACTERIZATION - CONCEPTS, REQUIREMENTS, AND METHODS

Global land-cover data are needed as baseline information for global c hange research, Multisource data, both coarse-resolution satellite dat a and ancillary data, were used to produce a land-cover characteristic s database for the conterqinous United States. Ancillary data, includi ng elevation and ecological region data sets, were critical to the dev elopment, refinement, and information content of each class in the dat abase. They contributed essential evidence for labeling and refining l and-cover classes where differing types were represented by single spe ctral-temporal signatures. The characterization process can be expande d to a global effort depending on (1) the availability of global satel lite coverage, (2) the quality and availability of ancillary data, and (3) the evolution of more sophisticated data visualization and analys is techniques.