Posts tagged GRACE

The GRACE satellites are a pair of twin observing devices that orbit the Earth 137 miles from one another. The Earth’s gravitational pull on the satellites varies depending upon the mass of what is below them at a particular time — a mountain, an ocean — and so by measuring slight perturbations in the distance between the two satellites, scientists detect these mass changes. But when does the Earth’s mass change in a significant way, one that would suggest an important anomaly? Mostly, this does not happen with the ground, rocks, mountains — at least not on human time scales. But water at the Earth’s surface moves around a great deal — California’s drought has been picked up by GRACE, as has dramatic melting of the glaciers of Alaska.

https://www.washingtonpost.com/news/energy-environment/wp/2015/11/04/nasa-can-now-detect-worrying-ocean-circulation-changes-from-space/