The IGBP-DIS global 1-km land-cover data set DISCover: A project overview

Since 1992 the international Geosphere Biosphere Programme's (IGBP) Data and information System (DIS) has been working towards the completion of a validated global land-cover data set, DISCover. This 1-km resolution data set consists of 17 cover classes identified on the basis of the science requirements of the IGBP's core projects. Discover has been created from over 4.4 Terabytes of data from the Advanced Very High Resolution Radiometer collected from 23 receiving stations. These data were processed and assembled into a coherent set of monthly Normalized Difference Vegetation Index composites (April 1992 to April 1993) and classified using unsupervised techniques with post-classification refinement. The first global land-cover classification wets completed in July 1997. The IGBP-DIS Land Cover Working Group, in turn, convened a Validation Working Group to provide and implement a validation method to provide statistical statements concerning the accuracy of the global land-cover product and to allow the estimation of the error variance in areal totals of classes globally and within regions. The validation workshop was completed in September 1998 and the analysis by March 1999. This paper describes the history of the Discover version 1.0 implementation.