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Cloud Fraction

The cloud maps show what fraction of an area was cloudy on average for the month. The measurements were collected by the MODIS sensors on NASA's Terra and Aqua satellites. Colors range from blue (no clouds) to white (totally cloudy).

Net Primary Productivity

These maps show net primary productivity, which is how much carbon dioxide vegetation takes in during photosynthesis minus how much carbon dioxide the plants release during respiration (metabolizing sugars and starches for energy) or decay. The data come from the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite. Values range from near 0 grams of carbon per square meter per day (tan) to 6.5 grams per square meter per day (dark green). A negative value means decomposition or respiration overpowered carbon absorption; more carbon was released to the atmosphere than the plants took in.

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

Cloud Fraction

Net Primary Productivity