Best practices for crop area estimation with remote sensing : GEOSS community of practice Ag 0703a

GEOSS (Global Earth Observation System of Systems) is an initiative to network earth observation professionals and researchers. GEOSS promotes technical standards for different aspects of remote sensing. This document is one of them; it is dedicated to the use of remote sensing for crop area estimation. The purpose is giving a simplified summary of the methods and of kinds of satellite data that can be used in operational projects and those that still require research. Satellite data: Synthetic Aperture Radar (SAR) images cannot be considered operational for crop area estimation, except for paddy rice. Coarse or moderate resolution optical images are operational only for landscapes with very large fields. In general terms, pure remote sensing approaches are acceptable in two cases: when a ground survey is not possible (because local authorities are not involved or due to security problems) or when the accuracy requirements are looser than the commission/omission errors. Crop area forecasting several months before harvest is not operational in general, but interesting indications can be given if the uncertainty on cultivated area is high.