Abstract – The Moderate Resolution Imaging Spectro-

radiometer (MODIS) sensors currently provide an 8-year suite of land products essential to Earth system science. The goal of the MODIS land validation group, in conjunction with the Land Product Validation (LPV) sub-group of the Committee on Earth Observing Satellites (CEOS) Working Group on Calibration and Validation (WGCV), is to foster the quantitative evaluation of geophysical products and convey validation data to users. MODIS land products are validated using various techniques to develop uncertainty information including: direct comparisons with in-situ field data collected at Earth Observing System (EOS) core sites and scientific observation networks (e.g. FLUXNET, AERONET); comparisons with data and products from higher spatial resolution sensors (e.g. Landsat); as well as inter-comparison of trends derived from independently-obtained reference dat