Scientists develop a new tool to measure worldwide groundwater sustainability

In a recent study published in Nature, Junior Fellow Tom Gleeson (McGill) and colleagues found that humans are overexploiting groundwater in many large aquifers critical to agriculture.

By combining data on groundwater use with current hydrology models, the team created a new way to measure global water use relative to water supply, which they call the ‘groundwater footprint’. The team found that certain countries, including the United States, China, Pakistan, Iran, India, Mexico and Saudi Arabia, greatly overused the groundwater available to them. This overexploitation by a few nations managed to drive up the global net value of the groundwater footprint.

“The groundwater footprint shows us which aquifers are being overused, and which are being used sustainably. Sustaining our groundwater resources is critical since it is used by 2 billion people daily,” says Dr. Gleeson.

With this new measurement tool in hand, Dr. Gleeson hopes to link groundwater footprint calculations with data derived from satellites in order to help guide policy.

“Our everyday food decisions are very important since certain foods, like meat, are very water intensive. Knowing how sustainable groundwater is in a certain area will help us to determine how to use it wisely.”

Dr. Gleeson’s large-scale approach to earth systems was inspired by CIFAR’s Earth System Evolution program.