More recent work by a portion of that same team, with much more information: http://www.jpl.nasa.gov/news/news.php?feature=4626 http://www.jpl.nasa.gov/news/ne

More recent work by a portion of that same team, with much more information: http://www.jpl.nasa.gov/news/news.php?feature=4626 http://www.jpl.nasa.gov/news/news.php?feature=4626 GRACE has opened up this whole area over the last few years. It's very hard to monitor groundwater, even well data is not that usable for various reasons.