Abstract:
Assessments of vegetation condition, cover, change, and processes are major components of global change research programs, and are topics of considerable societal relevance. Spectral vegetation indices are among the most widely used satellite data products, which provide key measurements for climate, hydrologic, and biogeochemical studies; phenology, land cover, and land cover change detection; natural resource management and sustainable development. Vegetation indices (VI) are robust and seamless data products computed similarly across all pixels in time and space, regardless of biome type, land cover condition, and soil type, and thus represent true surface measurements. The simplicity of VIs enables their amalgamation across sensor systems, which facilitates an ensured continuity of critical datasets for long-term land surface modeling and climate change studies. Currently, a more than two decades long NOAA Advanced Very High Resolution Radiometer (AVHRR)-derived consistent global normalized difference vegetation index (NDVI) land record exists, which has contributed significantly to global biome, ecosystem, and agricultural studies.