Monday , September 20 2021

Since 1979 ice loss in Antarctica has increased by 6 times: research



Global warming melt ice in Antarctica faster than ever before – about six times more than a year now, than 40 years ago – leading to increasingly high sea levels around the world, scientists are predicting on Monday.

Antarctic melting has already raised the global sea levels by more than half an inch (1.4 centimeters) between 1979 and 2017, according to a report by the National Academy of Sciences (PNAS).

It is expected that the pace of melting will lead to catastrophic sea-level rise in the coming years, says lead author Eric Rignot, head of the Department of Earth Systems Science at the University of California Irvine.

"As the Antarctic ice sheet continues to melt, we expect the multi-meter sea level to rise from Antarctica in the next centuries," said Rinoth.

A rise of 1.8 meters (six feet) by 2100, as predicted by some scientists in the worst scenarios, will flood many coastal cities where millions of people around the world live, according to preliminary studies.

In this study, researchers began the ancient estimate of the ice mass in Antarctica in 18 geographic regions.

The data came from high-resolution aerial photographs taken by NASA aircraft, along with a satellite radar from several space agencies.

The researchers found that from 1979 to 1990, Antarctica dropped annually an average of 40 billion tons of ice mass.

From 2009 to 2017, ice loss has increased by more than 6 times, to 252 billion tons per year.

Since 1979, the loss of ice in Antarctica has increased sixfold

Since 1979 ice loss in Antarctica has increased sixfold

Sabrina Blanchard, AFP

Even more disturbingly, the researchers found that the areas that were once considered "stable and immune to change" in East Antarctica also dump a lot of ice, the study said.

"The Wilkes Land farming in East Antarctica has always been an important player in mass loss, even in the 1980s, as our studies have shown," said Rynot.

"This region is likely to be more sensitive to climate than traditionally anticipated, and it is important to know, because it contains more ice than Western Antarctica and the Antarctic Peninsula."

– ice loss –

The total amount of ice in Antarctica, if all melt, will be enough to raise the sea level by 187 feet (57 meters).

Today, the largest amount of ice in Antarctica is concentrated in the east, where there is enough sea ice to pass 170 feet of sea level, compared with approximately 17 feet in the entire western Antarctic ice sheet.

The East Antarctic ice sheet is the largest in the world, containing about half the fresh water of the Earth.

So far, most studies have shown that most melting occurs in the West.

A landmark study published in Nature in June last year found that since the year 1992 Antarctic ice melt has tripled, but in the east did not show significant melting.

However, in a subsequent study published in Nature in September 2018, layers of sediments from the ocean floor were analyzed, where in recent times submerged basins in the Eastern Antarctic to the south of Australia melted about 125,000 years ago.

This research has shown that the mass pool will melt again, with a constant rise in temperature of only two degrees Celsius (3.6 Fahrenheit).

Recent studies show that eastern Antarctic melting deserves "more attention," according to PNAS.

The heating of the water in the ocean will only accelerate the loss of ice in the future, and experts say the sea level will continue to grow for centuries, regardless of what the person is doing now to curb climate change.

Recent studies have shown that the oceans are warming faster than previously thought by setting new heat records over the past few years.


Source link