Glaciers across Greenland have increasingly weakened in recent years, contributing to higher sea levels and broader climate impacts worldwide. A study published in Nature shows that ice loss from Greenland since 1985 has been 20% greater and faster than scientists once estimated.
A team of American researchers compiled 236,328 observations, gathered both manually and with computer assistance, to track glacier terminus positions monthly from 1985 through 2022. Artificial intelligence helped process the data and reveal clearer trends in ice retreat over the decades.
The researchers found that since 1985 the Greenland ice sheet shed about 5,091 square kilometers of ice, an area roughly equal to the size of La Rioja. In total terms, this corresponds to an estimated loss of about 1,000 gigatons of ice. Put differently, Greenland loses approximately 30 tons of ice every hour.
This level of ice loss has potential consequences, including higher sea levels that could exceed prior projections and influences on the global climate system through changes in ocean circulation.
Our understanding is refined by noting that the retreat of the calving front along the coastlines, where glaciers meet the sea, is often underrepresented in the ice-budget estimates. The latest assessment suggests that Greenland’s recent mass loss may be undercounted by as much as twenty percent in some evaluations.
Cities and countries are in danger
The study notes that while the mass loss has a limited direct effect on global sea level in the short term, it can alter ocean circulation and the distribution of thermal energy around the world, signaling further ice melt in the future.
The retreat of Greenland’s glaciers is consistently linked with the seasonal pattern of advance and retreat, typically peaking in May and reaching a low between September and October. This seasonal variability highlights glacier sensitivity to long-term climate trends.
Ice retreat is a global phenomenon with no true exceptions; glaciers everywhere respond to seasonal shifts, and those experiencing the steepest declines in recent decades show the strongest sensitivity to warming.
Scientists project that melting of the Greenland ice sheet is outpacing most planetary ice loss except for Antarctica, contributing more than twenty percent to sea level rise over the past twenty years.
Rising sea levels threaten coastal and island communities where hundreds of millions live, with the potential to drown cities and even nations over time.
“An unprecedented threat”
The Arctic region is warming at roughly four times the rate of the rest of the planet. Last year brought one of the hottest summers on record for the Arctic, underscoring the climate crisis. The faster surface melting of glaciers can accelerate ice loss from the interior of the ice sheet, increasing the total amount of meltwater reaching the oceans.
Scientists note that warm oceans absorb a large share of excess heat from greenhouse gas emissions, which is linked to the melting of major ice shelves that stabilize Greenland and Antarctica.
Researchers also raise concerns about potential changes to deep water currents, a key component of global climate models. Additional freshwater entering the oceans could influence the Atlantic Meridional Overturning Circulation, a complex system that transports heat from the tropics toward the northern hemisphere.
Changes in the AMOC and the ongoing ice sheet melt are among more than twenty climate emergencies identified by an international scientific group last year, described as an unprecedented threat to humanity and the planet.
Source: Nature, 2023 study, with attribution to the scientific team and institutional collaborators.
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Environmental authorities can be reached for further inquiries through official channels, and ongoing research continues to refine projections and policy implications.