NASA satellite reveals source of El Niño-fueled carbon dioxide spike

An artist's rendition of the OCO-2 Observatory. Credit: Courtesy NASA/JPL-Caltech

For every ton of carbon dioxide emitted by a power plant's smokestack or a car's exhaust pipe, some portion will stay in the Earth's atmosphere, raising global temperatures, while the rest is absorbed by the oceans or ecosystems on land.

But which parts of the ocean or biosphere act as net sources of carbon dioxide (CO2) and which take up more than they emit into the atmosphere, has been an open question. Figuring that out, as well as understanding what mechanisms govern that interplay and how they might change along with the climate, has been an open question and one that is key to understanding how global warming will progress.

The 2014 launch of the Orbiting Carbon Observatory-2 satellite was aimed at beginning to piece together some answers by monitoring the comings and goings of CO2 from the atmosphere with unprecedented precision and over large regions.