Home / World / A third of the Antarctic ice shelf is vulnerable to collapse as our planet warms.

A third of the Antarctic ice shelf is vulnerable to collapse as our planet warms.



In a predictive study, scientists found that 34% of the total area of ​​the Antarctic ice shelf, measuring about half a million square kilometers, could be unstable if global temperatures rise by four degrees, the researchers said, about 67% of the ice shelf area on the Antarctic Peninsula. There is a risk of instability under this situation.

The ice shelf is a permanent floating ice platform attached to an area of ​​ u200b u200bthe coast formed by glaciers that flow from the ground to meet the sea. They can help limit global sea-level rise by acting like dams, slowing the flow of ice and melting water into the ocean.

Each summer, the ice at the surface of the ice layer melts and flows into the small void of the snow below, which usually forms condensation. But when there is a lot of melting and there is little snow, this water will gather on the ice or flow into the crevices. This made the fissure deeper and wider, causing the ledge to break and collapse into the sea.

“Ice shelves are an important buffer in preventing terrestrial glaciers from flowing freely into the ocean and contributing to rising sea levels when they collapse, just like a giant cork that has been taken down.”

; Out of the bottle, the water from the glacier flows unimaginably into the sea. Study lead author Ella Gilbert, climate scientist at the University of Reading’s Meteorological Department, said in a statement.

Gilbert told CNN that lowland coastal areas, especially smaller islands such as Vanuatu and Tuvalu in the southern Pacific Ocean, are most at risk from sea-level rise worldwide.

“However, coastal areas around the world will be at risk and countries with less resources to mitigate and adapt to sea-level rise will suffer worse,” she said.

In a new study, which used high-resolution regional climate models to predict the effects of increased melting and runoff on ice shelf stability, the researchers said the limiting increases in temperature were. 2 degrees Celsius instead of 4 degrees Celsius will halve the vulnerable area and May avoid significant sea-level rise

The Intergovernmental Panel on Climate Change concluded in a key report that we have until 2030 to significantly reduce our dependence on fossil fuels and prevent the planet from reaching a critical threshold of 1.5 degrees Celsius (2.7 degrees Fahrenheit). Pre-industrial level

This image shows a huge iceberg that is separated from the Pine Island Glacier.

Global net carbon dioxide emissions will have to drop 45% from 2010 levels by 2030 and reach “net zero” around 2050 to maintain heat at 1.5 degrees Celsius.

“The findings highlight the importance of limiting global temperature rise, as outlined in the Paris Agreement, if we want to avoid the worst impacts of climate change, including an increase in global warming.” Sea level, ”added Gilbert.

In the Paris Agreement, 197 countries agreed to the goal of keeping global temperatures “below” 2 degrees Celsius above pre-industrial levels and trying to limit them to 1.5 degrees Celsius.

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But we are following a world warming 3.2 degrees Celsius by the end of the century.

Gilbert told CNN that the temperature increases mean melting is more frequent and intense.

The researchers identified four ice layers that would be threatened by warmer climates: the Larsen C, Shackleton, Pine Island and Wilkins ice shelves, which are at risk due to geography and the amount of water runoff in the area.

The Larsen C is the largest remaining ice shelf on the Antarctic Peninsula and the Pine Island Glacier has received a lot of attention in recent years due to its rapid melting in response to climate change, Gilbert said.

If these ice layers collapse altogether, there is no guarantee that the glaciers they are currently capturing will flow into the ocean, resulting in sea level rise, which can reach tens of centimeters.

The study was published Thursday in the journal Geophysical Research Letters.


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