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Total Rainfall

The rainfall maps show total monthly rainfall in millimeters as recorded by NASA’s Tropical Rainfall Measuring Mission (TRMM) satellite. High rain totals are represented in dark blue, while small rainfall totals are shown in white. TRMM measures rainfall in the tropics. High-latitude regions, where TRMM does not record rainfall, are gray.

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.

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

Total Rainfall

Aerosol Optical Depth