Carbon and Deserts: Aquifers Run Through It, Collect Human Emissions

In what would be good news with a few qualifiers, the huge aquifers under the world's deserts may be storing some of our carbon dioxide emitted by human activities. In fact, huge aquifers beneath the sands could be holding more carbon than--get ready--all the plants on land.

That's according to new research from a desert biogeochemist with the Chinese Academy of Sciences, Yan Li, and other researchers whose study was recently published in Geophysical Research Letters, a journal of the American Geophysical Union.

While we humans pretty regularly add carbon dioxide to the atmosphere through fossil fuel use and deforestation, perhaps 40 percent of this stays in the atmosphere and roughly 30 percent falls into the ocean, says the University Corporation for Atmospheric Research, in a release. 

While scientists know that all of the plants on land don't take up the remaining carbon, they've been searching for the so-called "missing carbon sink, as the release noted. 

For this study, scientists examined the flow of water through a Chinese desert. They learned that carbon is being absorbed by crops, released into the soil and transported in groundwater. Then it is stored deep below the desert and does not return to the atmosphere, the scientists note in the release.

Because of agriculture, 14 times more carbon than previously thought may be entering the aquifers. These underground pools, taken together, cover an area the size of North America, the release notes.

We can better predict future climate change and assess the Earth's carbon budget, the more that we know. For instance, one possibility is that if farmers and water managers know the role that inland deserts play in storing carbon, maybe they can alter how much carbon enters the underground reserves, said Michael Allen, a soil ecologist from the Center for Conservation Biology at the University of California-Riverside who was not an author on the new study, in the release.

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