Global navigation satellite systems (GNSS), which include GPS, are traditionally used for positioning, timing, and mapping information. In an open-access study published Feb. 27 in Geophysical Research Letters, MIT Haystack Observatory scientists report using existing GNSS satellites, in conjunction with 13 stations installed on the Ross Ice Shelf (RIS) in Antarctica, to measure atmospheric turbulence above the ice shelf that may have contributed to an unusual extensive surface melting in January 2016.