It is known fairly accurately how quickly global sea level can increase, but it is much more difficult to know all the different sources that contribute to this increase.
Using data collected by the GRACE satellite pair (Gravity Recovery and Climate Experiment), the authors of a new analysis have estimated more precisely than in previous studies of mass loss of the ice sheet of Antarctica. This improved accuracy has been achieved thanks to more accurately mapped to the ice, and to discern and count out mass changes caused by the flow of rock material beneath the surface of the Earth.
This greater accuracy achieved in the ice balance calculations has enabled an international team, led from the University of Newcastle in the UK, and determined that the net contribution of Antarctica to sea level rise is much lower than assumed above from other studies and estimates.
Matt King, Professor of Polar Geodesy at the University of Newcastle, and his colleagues have concluded that the large amount of water, by melting, flowing from West Antarctica, has been partially offset by the volume of water flowing into the continent as snow. This suggests that some studies have overestimated the contribution of Antarctica to the rapid rise in sea level that is detected in recent times.
In the new research have been also worked Rory Bingham, University of Newcastle, and Mike Bentley from Durham University in the UK.
The GRACE mission is collaboration between NASA and the German Space Agency (DLR). Both satellites were launched from the Plesetsk Cosmodrome in Russia on March 17, 2002, in the years since then, have provided many important data on the movement of water masses and their effects on the gravitational field of Earth. The satellites measure changes in the Earth’s gravity field caused by regional redistributions in the planet’s mass, including ice sheets, oceans and water in the soil and groundwater aquifers. From these data, it is possible to get much more information on various aspects of the Earth, including the rate at which the planet’s ice is melting from one year to another.