Satellitedata collected by ESA’s Gravity Field and Steady-State Ocean Circulation Explorer (GOCE) have been used to create a more accurate gravity map of global ocean currents. Users can register and access the data through ESA's website for free.
ESA’s GOCE satellite revealed earlier this month that the great Japanese Earthquake from 2011 caused a tiny change in the local gravity. The satellite mapped Earth's gravity for four years and clearly shows a disturbance after 2011.
ESA's Ocean Circulation Explorer (GOCE) mission will end this year. It has begun its decent towards Earth and will be reentering our atmosphere probably in mid-October. Having nearly tripled its planned lifetime, this Gravity field and steady-state mission has successfully mapped variations in Earth’s gravity with extreme detail.