NASA’s ICESat satellites have observed ice sheet losses in Greenland and Antarctica, pushing up sea levels by 14mm since 2003.
The study using ICESat and ICESat-2, which launched in 2018, have found that Greenland’s ice sheets lost on average 200 gigatons of ice per year and Antarctica lost 118 gigatons a year. A laser altimeter sent pulses of light to Earth’s surface and measured how long it took to return to the satellite. Pulse rates allow for a dense map of measurement over the ice sheet, with scientists determining how much the ice sheets changed over a year.
Researchers took tracks of earlier ICESat measurements and overlaid the tracks of ICESat-2 from 2019, and took data from sites where the two datasets overlapped. To calculate how much ice was lost, they developed a model to convert volume change to mass change by calculating densities across the ice sheets to allow the total mass loss to be measured.
To read the full story click here.