Climate Change: 40% of glaciers doomed to melt – the biggest threat to our future

The climate crisis is not only threatening the future, but is already forming our present. Nearly 40% of the glaciers that exist today are already doomed to melt due to greenhouse gas emissions from the burning of fossil fuels, according to a new study published in the Science. And the situation will become dramatically worse: if the global temperature rises by 2.7 ° C – a course on which the planet appears to be directed – the loss will reach 75%.

This huge decrease in ice cover will cause sea levels rising, endangering millions of people living in coastal areas. It will lead to mass population movements and will hit billions of people dependent on glaciers to regulate water in their agricultural crops.

Researchers point out that the drastic reduction in carbon emissions and the restriction of overheating could save half the mass of glaciers. Although this target seems increasingly impossible, the study shows that every tenth of the degree of overheating that is avoided can save 2.7 trillion tonnes of ice.

Lost 40% of glaciers

Unlike other studies, this was not limited to views by 2100, but also examined what will happen next. Until recently we knew that about 20% of glaciers would melt up to 2100, but now it seems that almost 40% is already lost. The consequences of this loss are multiple: rising seas, floods that will destroy settlements, wildlife and plant disappearances, and the collapse of tourist economies depending on glacier landscapes.

Dr Harry Zekollari, one of the researchers in the study, stressed that every slight increase in temperature is measured and that the decisions we make today will determine how many glaciers will be saved in the future. « Ice are good indicators of climate change, because melting shows us how the climate changes, » said Dr Lilian Schuster, a co -author of the exhibition. « But because glaciers react with a time delay, the real situation is much worse than it seems today in the mountains. »

She added that « it is not too late to act, because the study shows that every tenth of the lesser global heating counts », which can reduce the human pain caused by the loss of glaciers. « We hope this message will give people some hope that we can still do something. »

Until recently we knew that about 20% of glaciers would melt up to 2100, but now it seems that almost 40% is already lost.

The study was based on data from 200,000 glaciers in the world, except Greenland and Antarctica, and used eight different types of glaciers, based on real observations. Although researchers acknowledge that there are uncertainties in estimates, they stress that glaciers will surely lose much of their mass – and that in the most ominous version, 40% can reach up to 55%.

The clock counts down for the ‘glacier of revelation’

Thwaites, also known as the « glacier of the revelation », is one of the main forts that prevent this critical ice cream from collapsing, most of which is below sea level and contains enough ice to raise the level of the oceans by 3.3 meters. Unfortunately, this frozen giant – with Florida’s size – is also one of the most unstable and fastest glaciers in the world.

Although glaciers already knew how worrying the ice loss was, they recently discovered that it was exposed to much warmer waters than they thought. According to a study published last week, scientists, with the help of satellite images and hydraulic models, found that warm tidal currents penetrate the massive layer of ice at depths reaching 6 kilometers, causing « intense ».

« We must definitely understand how quickly the ice is changing and how quickly it will change in the next 20 to 50 years, » said Christine Dow, an Associate Professor of glacier at the University of Wallerlou and one of the authors of the study. « We hoped that it would take a hundred, maybe five hundred years to lose this ice. Now we are seriously worried that it happens much earlier. « 

The sea level rises

As climate change steadily raises the temperature of the planet, glaciers and frosts in the polar and mountainous areas inevitably melt. Water and peeled ice volumes end up in the oceans, raising their level. Since 1880, world sea level has risen about 23cm, and any sharp increase could be devastating for coastal cities such as New York, Mumbai and Shanghai. Countries with very low altitude, such as the Marshall Islands and Tuvalu, are in danger of sinking entirely.

Thwaites, often called a « glacier of the day of crisis », is already responsible for 4% of the global sea level rise and loses 50 billion tonnes of ice each year. If it collapses, it could raise the ocean level by 65cm worldwide. « It may not sound much, but if you consider the huge amount of ocean water in the world, it’s a huge volume, » Dow commented.

The study, published in the journal Proceedings of the National Academy of Sciences, showed that tidal movements – which raise and lower the ice – allow water to penetrate deeper and deeper under the ice cover and weaken its connection to the seabed. Although the same phenomenon had been recorded in the Greenland Petermann glacier, it had never been observed in Antarctica so far. Thwaites has about eight times of ice in contact with the ocean over Petermann.