MODIS CALIBRATION - A BRIEF REVIEW OF THE STRATEGY FOR THE AT-LAUNCH CALIBRATION APPROACH

The Moderate-Resolution Imaging Spectroradiometer (MODIS) is a key ins trument on the NASA Earth Observing System. It is a multispectral sens or that will be used to track long-term global change in the land, atm osphere, and ocean components of the earth. Major advances are being m ade with MODIS over previous sensors in the form of improved on-orbit sensor characterization and calibration using a system of onboard cali brators. This article describes those calibrators and provides an earl y estimate of the expected accuracy for the MODIS calibrated datasets resulting from the use of these calibrators. The focus of the paper is the calibration approach that is being implemented at-launch for the top-of-the-atmosphere data products.