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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.

Land Surface Temperature

Land surface temperature is a measurement of how hot the land is to the touch. It differs from air temperature (the temperature given in weather reports) because land heats and cools more quickly than air. This image depicts average monthly land surface temperature in degrees Celsius as measured by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite. The warmest temperatures are pale yellow, while the coldest temperatures are dark blue. Moderate temperatures are depicted in shades of pink and purple. Regions where land surface temperature measurements were not possible are gray.

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

Aerosol Optical Depth

Land Surface Temperature