Global Maps

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Aerosol Optical Depth

Aerosol Optical Depth
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Water Vapor

Water Vapor
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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.

Water Vapor

The water vapor maps show the total amount of water vapor in the column of air between the surface and the top of the atmosphere on average for the month. The observations were made by the MODIS sensor on NASA's Aqua satellite. Places where the air was dry are yellow, while places where water vapor was abundant are blue.

View, download, or analyze more of these data from NASA Earth Observations (NEO):
Aerosol Optical Depth
Water Vapor

Aerosol Optical Depth & Water Vapor