Will increased consumption of groundwater leave a nation in short supply?
During the past decade, groundwater beneath the northern Indian states of Punjab, Haryana, and Rajasthan has decreased by more than 88 million acre-feet. That's nearly eight times the amount held in Lake Mead, the largest reservoir in the United States. Now at risk of experiencing severe shortages of this vital resource are the 120 million inhabitants of those regions. Using NASA's twin GRACE (Gravity Recovery and Climate Experiment) satellites, scientists measured tiny shifts in the Earth's gravitational field to determine the rate of groundwater change in India. Areas in red had slightly less mass due to a net loss of groundwater and therefore exhibited a weaker gravitational pull on the orbiting satellites. Areas in blue had greater mass and a stronger gravitational pull due to a net gain. Watch the data visualization in the first video below to see how India's groundwater supply declined over the six-year period between 2002 and 2008.