MODIS Surface Reflectance Product

Principal Investigators:

Eric Vermote, Chris Justice, Elizabeth Satterfield, John O’Bannon, Nazmi Saleous (Raytheon ITSS), James Ray (SSAI), Francois Petitcolin (ACRI-US)

MODIS is a NASA instrument on board two polar orbiting platforms, Aqua and Terra, which are part of NASA’s Earth Observing System. The MODIS surface reflectance Team, which is part of the MODIS Science Team, has been involved in the design of the instrument specifications, the development of algorithms for atmospheric correction over the whole solar spectrum, global product generation, and validation. The MODIS instrument provides major advances in moderate resolution earth observation. Improved spatial resolution for land observation at 250m and 500m and improved spectral band placement provides new remote sensing opportunities. NASA has invested in the development of improved algorithms for MODIS, which will provide new data sets for global change research. Surface reflectance is one of the key products from MODIS and is used in developing several higher-order land products. The surface reflectance algorithm builds on the heritage of the AVHRR and SeaWiFS algorithms, taking advantage of the new sensing capabilities of MODIS. Atmospheric correction, by the removal of water vapor and aerosol effects, provides improvements over previous coarse resolution products and the basis for a new time-series, which will extend through to the NPOESS generation imagers. The algorithm is being validated by comparison to atmospherically corrected high spatial resolution data (ETM+) at AERONET sites validated themselves against ground measurements. In addition, MODIS middle infrared, longwave infrared, and cirrus (1.38m) bands are used in a state of the art could/cover cloud shadow detection algorithm, which is critical in the downstream use of the generated products. The surface reflectance products are distributed by the USGS, Eros Data Center.

Figure Caption: The impact of aerosols and their correction for a MODIS granule acquired over South Africa on September 13,2001 at 8:45GMT: RGB image of the MODIS bands 1,4,3 (left not corrected for the aerosol effect), RGB image of the surface reflectance’s in bands 1,4,3 (right corrected for aerosol effect).

Example publications: Vermote E.F., El Saleous N., Justice C., 2002, Atmospheric correction of the MODIS data in the visible to middle infrared: First results, Remote Sensing Of Environment, 83, 1-2, 97-111. Petitcollin F. and Vermote E. F., 2002, Land Surface Reflectance, Emisivity and Temperature from MODIS Middle and Thermal Infrared data, Remote Sensing Of Environment, 83,1-2,112-134.