Spaceborne detection of localized carbon dioxide sources

Spaceborne measurements by NASA's Orbiting Carbon Observatory-2 (OCO-2) at the kilometer scale reveal distinct structures of atmospheric carbon dioxide (CO2) caused by known anthropogenic and natural point sources. OCO-2 transects across the Los Angeles megacity (USA) show that anthropogenic CO2 enhancements peak over the urban core and decrease through suburban areas to rural background values more than similar to 100 kilometers away, varying seasonally from similar to 4.4 to 6.1 parts per million. A transect passing directly downwind of the persistent isolated natural CO2 plume from Yasur volcano (Vanuatu) shows a narrow filament of enhanced CO2 values (similar to 3.4 parts per million), consistent with a CO2 point source emitting 41.6 kilotons per day. These examples highlight the potential of the OCO-2 sensor, with its unprecedented resolution and sensitivity, to detect localized natural and anthropogenic CO2 sources.