US: Recognising the need of many users who depend on consistently calibrated radiometric data to conduct broad investigations of historical land surface changes, the U.S. Geological Survey (USGS) has begun production of higher-level (more highly processed) Landsat data products to help advance land surface change studies. One such product is Landsat surface reflectance data. Surface reflectance data products approximate what a sensor held just above the Earth’s surface would measure, if conditions were ideal without any intervening artifacts (interference or changing conditions) that may come from the Earth’s atmosphere, different levels of illumination, and the changing geometry of the view by the sensor from hundreds of miles above the Earth. The precise removal of atmospheric artifacts increases the consistency and comparability between images of the Earth’s surface taken at different times of the year and different times of the day.
Source: USGS
