By precisely measuring the elevation of land ice, Atlas and ICESat-2 will help scientists develop a better sense of how much and how quickly that ice is melting in a warming world.
We already know that the melting that is taking place in the enormous storehouses of fresh water locked into the ice sheets of Greenland and Antarctica is increasing sea levels by a millimeter a year, accounting for a third of the total rise. (Other glaciers and ice caps account for another third, and the rest can be attributed to the fact that warming ocean water expands in volume.) A deeper and more precise understanding of the melting will lead to a better understanding of sea level rise.
And even though the melting of ice floating in the oceans does not add to sea level rise, measuring the height of that ice will also shed light on the effects of the fresh water on things like ocean currents.
Tom Neumann, deputy project scientist for the new satellite, said it would provide “a phenomenal picture” of changes in the planet’s ice sheets and water. “It’s going to enable science discoveries in the cryosphere and polar research for years to come,” he said.
For more news on climate and the environment, follow @NYTClimate on Twitter.
Source : https://www.nytimes.com/2018/09/14/climate/nasa-ice-satellite-launch.html257