Mother Nature Network: The Earths largest aquifers, a source of water for more than 60 million people, are depleting fast, likely due to a growing world population and industries such as agriculture, according to a new study. Scientists at the University of California, Irvine led the research that used NASAs GRACE satellite to find out just how much groundwater were losing and how quickly. The detailed images show that 21 of the worlds 37 largest aquifers are past sustainability tipping points, meaning that those...