ONE nation’s thirst for groundwater is having an impact on global sea levels. Satellite measurements show that northern India is sucking some 54 trillion litres of water out of the ground every year. This is threatening a major water crisis and adding to global sea level rise.

Virendra Tiwari from the National Geophysical Research Institute in Hyderabad, India, and colleagues used gravity data from the GRACE satellite to monitor the loss of continental mass around the world since 2002. Regions where water is being removed from the ground have less mass and therefore exert a smaller gravitational pull on the …