The two studies, which are being published in the journal Water Resources Research, represent the first effort to use satellite data to look at groundwater loss all over the planet. The researchers utilized data collect by NASA’s twin Gravity Recovery and Climate Experiment [GRACE] satellites. The latter measure dips and bumps in the Earth’s gravity which are affected by the weight of groundwater.
The scientists examined the planet’s 37 biggest aquifers over a 10-year period ending in 2013. Of those, eight were overstressed, with no natural replenishment to offset human use. Another five aquifers were extremely or highly stressed, meaning that even though they still had some water flowing into them, it wasn’t enough to maintain their water levels.
The most critically endangered water supply in the world was the Arabian Aquifer System, which supplies water to 60 million people in the Middle East. Next on the list was the Indus Basin aquifer of northwestern India and Pakistan, while the Murzuk-Djado Basin in northern Africa was third. [...]********