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Aerosol Optical Depth

The aerosol maps show average monthly aerosol amounts around the world based on observations from the MODIS sensor on NASA's Terra satellite. Satellite measurements of aerosols, called aerosol optical thickness, are based on the fact that the particles change the way the atmosphere reflects and absorbs visible and infrared light. An optical thickness of less than 0.1 (palest yellow) indicates a crystal clear sky with maximum visibility, whereas a value of 1 (reddish brown) indicates very hazy conditions.

Net Radiation

The map of net flux shows monthly changes in the balance of incoming and outgoing energy on Earth as measured by the Clouds and the Earth Radiant Energy System (CERES) sensor on NASA's Terra and Aqua satellites. Places where the amounts of incoming and outgoing energy were in balance are yellow. Places where more energy was coming in than going out (energy surplus) are red. Places where less energy was coming in than going out (energy deficit) are blue-green.

View, download, or analyze more of these data from NASA Earth Observations (NEO):

Aerosol Optical Depth

Net Radiation