Satellite measures gravity's effect on climate change

Paris (AFP) March 9, 2011 After nearly two years in space, the European satellite "GOCE" has collected the raw data needed to map variations in Earth's gravity field, the European Space Agency has said. The data will help scientists better understand the impact of climate change on sea levels, ice sheets, and ocean circulation systems.
ESA launched the five metres long (16 feet), 1,050 kilogrammes (2,310 pounds) satellite in 2009 as part of its "Earth Explorer" programme.
From its relatively low orbital position 260 kilometres (160 miles) above the planet, GROCE can, with unprecedented accuracy, detect minute changes in Earth's gravity field.
Gravity's pull is not felt equally across the planet. Rather, Earth's slightly flattened shape and the irregular distribution of heavy rock lead to inconsistent gravitational forces across different regions.
Scientists at ESA will use the new data to generate a planetary "geoid," a hypothetical model of how gravity would shape a global ocean in the absence of tides and currents.