Thursday 14 June 2018

Antarctica lost 219 billion tonnes of ice since 2012 up from the 76 billion recorded in previous years global sea levels could be 3 feet higher by 2070

The Antarctic ice sheet is melting faster than ever - with global sea levels rising more than a half-millimeter every year since 2012, according to scientists.
Antarctica has lost 219 billion tonnes of ice since 2012, up from the 76 billion that was recorded in previous years.
Researchers fear that if the thaw continues to increase at this rate, low-lying communities and coastal cities from New York to Shanghai could be under water by 2100.
"The sharp increase ... is a big surprise," Professor Andrew Shepherd, of the University of Leeds in England, told Reuters.
Working among a team of 80 scientists from 14 different countries, Shepherd helped compile data for a groundbreaking climate study known as the Ice Sheet Mass Balance Inter-comparison Exercise (IMBIE).
The results were published in the journal Nature on Wednesday.
"We have long suspected that changes in Earth's climate will affect the polar ice sheets," Shepherd explained in a statement published by Leeds.
"Thanks to the satellites our space agencies have launched, we can now track their ice losses and global sea level contribution with confidence."
Since 1992, scientists found that ice losses contributed to a sea level rise of 0.76 cm.
The West Antarctic ice sheet has lost nearly three trillion tonnes of ice during this span - with a large chunk of the numbers coming in the last few years, according to research.
From 1992 to 2012, sea levels were said to be rising at an average of 0.2 mm each year due to ice loss.
The tally has since jumped to 0.6 mm a year.
"According to our analysis, there has been a steep increase in ice losses from Antarctica during the past decade, and the continent is causing sea levels to rise faster today than at any time in the past 25 years," Shepherd said.
"This has to be a concern for the governments we trust to protect our coastal cities and communities." A separate study - also published in Nature this week - found that global sea levels could be 3 feet higher by 2070 if nothing is done to curb the ice loss in the next few years.
If the West Antarctic ice sheet continues to disintegrate and ends up collapsing, then we could see an increase of more than 10 feet.
"Some of the changes Antarctica will face are already irreversible, such as the loss of some ice shelves, but there is a lot we can prevent or reverse," said Martin Siegert, study co-author and professor at the Grantham Institute in London.
"To avoid the worst impacts, we will need strong international cooperation and effective regulation backed by rigorous science," he explained in a statement.
"This will rely on governments recognizing that Antarctica is intimately coupled to the rest of the Earth system, and damage there will cause problems everywhere."