Using GPS to Track Global Warming
One tricky aspect of measuring the rate of melting of Greenland and Antarctica's huge ice sheets has been accounting for an effect known as "post-glacial rebound" of the Earth's crust. This effect — which occurs when the crust is relieved of the burden of ice — manifests itself as a shifting and springing back of the planet's crust.
In an effort to correct for this effect, an international team of scientists are mounting the first expedition to install 24 GPS stations around Greenland's coast. They will be able to monitor even minute vertical and lateral changes in the Earth's crust — which they'll beam out as readings. To make sure they stay continuously powered, the scientists will be equipping them with large battery packs and solar panels. The first station was successfully installed last week near Ilulissat, on the west coast, by the team — comprising members from Denmark, the U.S. and Luxembourg — with the next one to follow near Kulusuk, on the east coast. The data obtained from these stations will be combined with data from sensors measuring elevation changes, glacial outflow rates and the mass of ice sheets to provide a more comprehensive assessment of the sheets' melting. This information should nicely complement that recorded by GRACE (Gravity Recovery and Climate Experiment) — a NASA satellite system — which takes regular ice-sheet mass readings but can't tell which particular areas are losing mass.
After finishing their work in Greenland, the scientists plan on moving on to Antarctica, where they will install 16 more stations. With sea levels predicted to rise almost 70 m if all the ice sheets were to melt, the scientists are hoping to take advantage of the data gleaned from these GPS stations to gain a better understanding of the sheet changes and anticipate the likely effects precipitated by further global climate change.
Via ::Technology Review: A Clearer Picture of Global Warming (news website)
See also: ::Solar Powered GPS: Prayers are Answered, ::Proporta's Solar Bluetooth GPS and Solar ChargerImage courtesy of David Talbot