Greenland and Antarctica lost about 11.3 trillion metric tons (12.5 trillion US tons) of ice between 1979 and 2023. Spread over the continental United States, that much ice would stand about 1.5 meters (5 feet) deep.
The meltwater raised global sea level by about 3.1 centimeters (1 inch). According to the authors, every centimeter of rise exposes another two to three million people to flooding each year.
How it was measured
The data combine 45 independent measurements from 27 satellites into a single dataset. Ines Otosaka of Northumbria University led the work, published in Scientific Data.
"There is a clear trend that the ice sheets are losing more mass," Otosaka says.
Speeding up
From the 1970s to the 1990s the ice sheets were largely stable. Losses then accelerated, with the biggest jump in the past decade. From 2020 to 2023 the loss eased temporarily, which the authors attribute to weather rather than a reversal.
About five-sixths of the loss comes from warmer ocean water eating at the ice from below and at the edges, not from warm air. Greenland's Jakobshavn glacier is retreating 50 meters (164 feet) a day.
"The changes are tracking decades behind global warming," says co-author Andrew Shepherd, also of Northumbria.
Co-author Eric Rignot of UC Irvine puts it plainly: "The ice sheets are melting away fast."
