Groundwater use adds CO2 to the air

Using groundwater for crop irrigation or industrial purposes adds more planet-warming carbon dioxide to the atmosphere than volcanoes do, a new study suggests.

As water soaks through soil, it picks up carbon dioxide that’s generated when organic matter in the soil decomposes. On average, groundwater holds from 10 to 100 times as much carbon dioxide as the water in lakes and rivers, says Gwen L.