A satellite mission that bounces laser light off the ice sheets of Antarctica and Greenland has found that hundreds of billions of tons’ worth of ice are being lost every year due to Earth’s changing climate.
Scientists involved in NASA’s ICESat-2 project report in the journal Science that the net loss of ice from those regions has been responsible for 0.55 inches of sea level rise since 2003. That’s slightly less than a third of the total amount of sea level rise observed in the world’s oceans over that time.
To track how the ice sheets are changing, the ICESat-2 team compared the satellite’s laser scans with similar measurements that were taken by the original ICESat spacecraft from 2003 to 2009. (ICESat stands for “Ice, Cloud and Elevation Satellite.”)
“If you watch a glacier or ice sheet for a month, or a year, you’re not going to learn much about what the climate is doing to it,” Ben Smith, a glaciologist at the University of Washington and lead author of the Science paper, said in a NASA news release. “We now have a 16-year span between ICESat and ICESat-2 and can be much more confident that the changes we’re seeing in the ice have to do with the long-term changes in the climate.”