With an annual loss of 264 gigatons, melting ice from the Greenland Ice Sheet has become the primary source of sea level rise, and the rate of melting has been increasing since the 1980s. A study published this year in Communications Earth & Environment reported that ice-marginal lakes (IMLs) are a critical factor accelerating the melting of Greenland’s glaciers.

IMLs are meltwater lakes that form in the hollows left by retreating glaciers. When a glacier flows into one of these lakes, the water lifts the ice’s edge, reducing friction and increasing the likelihood of large ice slabs to break away. Using satellite data, researchers have discovered that glaciers terminating in IMLs move three times faster than those ending on land. This rapid flow delivers more ice to lower, warmer elevations, accelerating the melting process. By incorporating the effects of IMLs into future climate models, scientists can enhance their ability to predict sea-level changes.