Since 1979, glaciers in Greenland and Antarctica have lost approximately 12.5 trillion tons (11.3 trillion metric tons) of ice, according to a comprehensive scientific analysis of satellite data. This ice loss, equivalent to covering the continental United States with a five-foot layer of ice, is accelerating due to climate change and is driving global sea levels higher.
The study, published in the journal Scientific Data, reveals that the majority of the ice melt—around five-sixths—is caused not by warmer air temperatures but by rising ocean temperatures eroding the ice sheets from below and along their edges. This process causes glaciers to flow more rapidly into the oceans, contributing to sea level rise. Since 1979, the meltwater from these ice sheets has raised global sea levels by about one inch (3.1 centimeters), adding to the rise caused by other climate-related factors. While an inch may appear minor, researchers emphasize that each incremental increase in sea level results in flooding risks for millions of people worldwide. Specifically, every third of an inch (or centimeter) of sea level rise exposes an additional 2 to 3 million individuals to annual flooding, said lead study author Ines Otosaka of Northumbria University.
Greenland's Jakobshavn glacier, one of the fastest retreating glaciers, has been observed to recede by up to 164 feet (50 meters) daily. The international research team, coordinated by the European Space Agency and incorporating NASA satellite data, was able to extend ice volume records for Antarctica back to 1979 and Greenland to 1972, longer than previous studies that relied mainly on European data beginning in the 1990s.
The findings demonstrate that the ice sheets were relatively stable through the 1970s to 1990s, but significant melting began in the early 21st century, intensifying notably during the 2010s. "There is a clear trend that the ice sheets are losing more mass, and it has been increasing from decade to decade," Otosaka said, highlighting the link to climate change. Co-author Andrew Shepherd also from Northumbria University noted that because ice sheet changes lag behind atmospheric warming by several decades, melting is expected to continue for many years even if global temperatures stabilize.
The study identified a brief period from 2020 to 2023 in which the acceleration of ice loss appeared to slow. However, scientists attribute this to short-term weather fluctuations rather than a reversal of the long-term trend. For example, East Antarctica experienced record snowfall during this time, temporarily offsetting rapid melting in the more vulnerable West Antarctic Ice Sheet. Researchers assert that this is merely a temporary pause in an ongoing upward trajectory.
A distinguishing feature of the recent ice loss is the dominance of dynamic processes—abrupt, large-scale movements of ice—rather than gradual surface melting. These processes heighten the risk of passing critical tipping points that could lead to irreversible ice sheet collapse. New York University ice scientist David Holland, who was not involved in the study, affirmed that the convergence of independent measurement methods strengthens confidence in the results, emphasizing that the upward trend in ice loss is clear and significant.
Other experts, such as University of Colorado scientist Ted Scambos, note that the potential for sudden Antarctic mass loss remains a complex and urgent challenge for global climate management. While society now possesses better scientific understanding of these risks than ever before, effective action to mitigate long-term impacts remains limited. The study underscores the necessity for sustained monitoring and robust climate policies to address escalating ice sheet melt and its implications for global sea level rise.