Even if the world stopped emitting greenhouse gases today, the ice sheet would lose more than 110 trillion tons of ice, causing global sea levels to rise by nearly 30 cm. Greenland currently contains enough ice to raise sea levels by about 7 meters. Complete melting of the ice sheet will not happen in our lifetime, but the potential consequences for future generations will be catastrophic.
The Greenland Ice Sheet contributes more to sea level rise than any other ice mass, including Antarctica. Melting sea ice does not contribute to sea level rise because it is already in the ocean. But when land ice melts, it flows into the ocean, raising sea levels by about three-quarters of a millimeter per year. According to the Intergovernmental Panel on Climate Change, Greenland is losing mass twice as fast as Antarctica.
The GreenDrill Project found that one of the rock samples had been exposed to sunlight for the past 1.1 million years, meaning that under climate conditions not very different from those we live in today, Greenland was almost completely ice-free. A repetition would be a disaster, shares The Washington Post.
European climatologists have found that ice shelves in northern Greenland have decreased in volume by more than 1/3 compared to their state in 1978, TASS reports citing the scientific journal Nature Communications. This conclusion was reached by a group of European climatologists from the University of Grenoble (France) while studying the condition of the eight largest ice shelves surrounding the northern part of Greenland. So far, these ice masses are considered relatively stable compared to their southern neighbors, which have been actively shrinking in area and volume in recent decades and are losing two to three times more mass than northern glaciers.
Scientists became interested in how the condition of Greenland’s northern coastal glaciers has changed in recent decades, during which average temperatures in the Arctic have increased by 4–9°C. To obtain this information, the scientists analyzed data and images of northern Greenland obtained by NASA’s Icebridge aircraft, as well as the ERS, ICESat, Landsat and Sentinel family of scientific probes, between 1978 and the present.
As a result, the volume of sea glaciers off the northern coast of the island decreased by 445 cubic kilometers (443 billion tons of water), and their area decreased by more than 2,000 square kilometers, about 1/3 of the original area. Scientists expect these processes to accelerate in the near future as Arctic sea temperatures rise, which could lead to the collapse of all of Greenland’s ice shelves and very rapid sea level rise in the coming decades and centuries.
The GreenDrill project is an attempt to extract bedrock samples from beneath the Greenland ice shell. The Greenland ice sheet is patient number one in the climate system, according to scientists from an expedition to study the state of the ice in this part of the world. And, according to them, the glaciers underwent a biopsy to evaluate the “patient’s” condition.
Rocks that were buried under ice sheets carry chemical traces of the last time they saw sunlight. By collecting material from different parts of Greenland, the GreenDrill team hopes to determine which parts of the ice sheet disappear first when temperatures begin to rise. Their findings could help improve the models scientists use to predict how Greenland will melt under human-caused warming and what that means for rising sea levels.
At the same time, scientists led by Donghyuck Lee from Seoul National University conducted predictive modeling of sea level rise until the mid-21st century, which will occur only due to ice loss in Greenland and Antarctica. To do this, they used observational data on the dynamics of ice sheets from 1992 to 2020 and extrapolated their melting rates over the next 30 years.
To calculate the surface mass balance, the authors took an ensemble average of 23 CMIP6 climate models under two anthropogenic emissions scenarios—one with severe emissions constraint and one with almost no constraint. Korean glaciologists have concluded that sea level rise on the planet will be heterogeneous due to gravitational and rotational effects: at low latitudes it will be maximally pronounced, and in close proximity to ice sheets it will be minimal.