Home https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ Science https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ Greenland’s ice sheet is melting as fast as it has at any time in the last 12,000 years, according to a study

Greenland’s ice sheet is melting as fast as it has at any time in the last 12,000 years, according to a study



But in the context of Earth’s 4.5 billion-strong history, melting every year or even decades is a blink of an eye.

Whether the rapid disintegration we see today in Greenland is comparable to everything that has happened in the past is a question on which science is not entirely clear.

Over the last two decades, Greenland’s ice sheet has melted at a rate of approximately 6,100 billion tons per century, approaching only during the warm period of between 7,000 and 10,000 years.

“We know there are a lot of variations from year to year, so what we were interested in was catching more significant trends for decades and maybe a century,” said Jason Briner, a professor of geology at the University of Buffalo. and the lead author of the study. “And when you do that and think about the direction Greenland is heading in this century, it̵

7;s very clear that we’re in pretty abnormal times.”

A chart provided by the study's authors shows how quickly Greenland's melting has accelerated and how unprecedentedly it has been compared to the rate of 12,000 years.

The big difference between now and then? The influence of human activity.

The melting observed today is mainly due to greenhouse gas emissions, while the warming that occurred thousands of years ago is the result of natural climate variability, Briner said.

How far Greenland will melt depends on us.

In a scenario in which humans continue to increase concentrations of heat-retaining gases in the atmosphere, ice loss in Greenland could reach unprecedented levels, with more than 35.9 trillion tons of ice potentially lost by the end of this century.

At the moment, Brainer says the current melting rate is being closely monitored with this worst-case scenario.

A new study finds that Greenland's ice sheet - which contains enough water to raise sea levels by 24 feet - is melting as fast as it has ever in the past 12,000 years.

However, if the world decides to reduce emissions enough so that global warming peaks around 2050, ice losses in this century could last up to 8.8 trillion tonnes – still a huge amount, but only enough to raise sea levels by about an inch compared to the approximately 4 extra inches we can expect in a high-emission scenario.

“Humanity has the buttons and we can turn them to decide what the ice sheet will do,” he said.

What will happen to the ice sheet of Greenland and others around the world will determine the future for the millions of people living off the coast of the world.

In terms of its potential for sea level rise, Greenland is the second most important ice sheet in the world, behind only Antarctica.

Greenland’s ice sheet contains enough water to raise the sea level by 24 feet. Over the last 26 years, meltwater from Greenland has raised sea levels by 0.4 inches and is currently the biggest contributor to rising sea levels.
Melting from Antarctica, on the other hand, is currently responsible for 20-25% of global sea level rise, but is likely to surpass Greenland as the largest global contributor.
Antarctica holds enough water to raise sea levels by about 200 feet, and scientists have recently discovered alarming vulnerabilities in some of its most important glaciers.
Flood rise could cost our planet $ 14.2 trillion, says study
A report by last year’s UN Intergovernmental Panel on Climate Change warns that sea level rise is likely to exceed 3 feet by the end of this century if greenhouse gas emissions are not managed.
Rising seas are already causing problems in many coastal areas. And for places like New York and Shanghai, 3 feet or more of sea level rise can cause a catastrophe.
Another recent study found that rising seas could cost the global economy $ 14.2 trillion in lost or damaged assets by the end of the century and expose 287 million people to occasional floods, up from 171 million today.

“It is clear that sea levels have risen since the melting of ice 12,000 years ago and have affected people, but these people were much more widespread and they did not have garages and integrated modern water systems serving millions of people. “Said Richard Alley, a professor of geoscience at Penn State University who did not participate in the study, published by Nature.

“These results show that human decisions about our energy systems are really important in deciding what sea level rise we are facing from melting ice in Greenland.”


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