Climate crisis: Greenland lost 1,140 billion tons of ice in just 40 years
In a new study, Nasa’s Jet Propulsion Laboratory has unveiled alarming findings about the state of Greenland’s ice sheet hinting at the growing threats of the climate change.
The comprehensive analysis, which scrutinised nearly four decades of satellite data, reveals that the ice sheet has lost approximately 21 per cent more mass than earlier estimates suggested.
The research, published in the journal Nature, which meticulously examined glacier positions from 1985 to 2022, found that out of 207 glaciers, a staggering 179 have retreated significantly. This retreat is primarily occurring in fjords below sea level around Greenland’s periphery, where ancient glacial ice once stood.
As these glaciers calve and retreat, they are likened to “pulling the plug out of the fjord,” allowing ice to drain into the ocean more rapidly, explains Chad Greene, a leading glacier scientist at JPL.
This additional loss of ice, amounting to roughly 1,140 billion tons, was previously unaccounted for by the international Ice sheet Mass Balance Inter-comparison Exercise (IMBIE). While this ice does not directly contribute to rising sea levels since it breaks off from areas already submerged or floating, it signifies a substantial influx of fresh water into the oceans.
This could potentially disrupt the Atlantic Meridional Overturning Circulation — a crucial component of the global oceanic “conveyor belt”—with far-reaching implications for global weather patterns and ecosystems.
The study also highlights that the ice retreat has consistently outstripped growth since the turn of the century, with marked recession beginning after 2000. Zachariae Isstrom, a glacier in northeast Greenland, suffered the most significant loss, followed by Jakobshavn Isbrae and Humboldt Gletscher. Only one glacier, Qajuuttap Sermia, showed any growth, but its gains were minimal compared to the overall losses.
Researchers discovered a correlation between glaciers with the largest seasonal fluctuations in their ice front positions and those experiencing the greatest overall retreat. This suggests that glaciers most sensitive to summer warming are also the most vulnerable to climate change.
Alex Gardner, a JPL cryosphere scientist and co-author of the study, emphasises the importance of this research, stating, “Previously, we had bits and pieces – lots of local studies. But what this study offers is a systematic and comprehensive view that has led to some pretty significant insights that we didn’t have about the ice sheet before.”
The findings point to the urgent need for continued monitoring and research to understand the full impact of climate change on planet’s delicate polar regions.