Missing Carbon Sink Found In Desert Aquifers

Researchers find that as water moves through irrigated fields, it gathered dissolved carbon and moved it underground. (Credit: Yan Li)

Scientists have long searched for a missing carbon sink. They accounted for carbon in the air, sea and in plants on land, but some carbon was unaccounted for in the land part of the equation, left unseen. According to an American Geophysical Union press release, the missing carbon sink has been located at last, not where it was expected: deep below desert sands in underground aquifers.

Scientists with the University Corporation for Atmospheric Research gathered samples from a Chinese desert called Tarim Basin to make the find. Those formed the basis of the discovery. Not only is the underground desert aquifer carbon sink large, but it is believed that the amount of carbon it absorbs is greater than that stored by all plants on land. It is estimated that the desert aquifers are storing approximately 1 trillion metric tons of carbon.

Part of the reason so much carbon is stored in these systems is because, unlike most other carbon sinks, it isn’t likely that desert aquifers allow the carbon to escape back into the atmosphere. This is due to the desert sand layer over the aquifers preventing carbon from returning to the surface.

Top image: Researchers find that as water moves through irrigated fields, it gathered dissolved carbon and moved it underground. (Credit: Yan Li)