West Antarctic Ice Sheet is on the verge of a 'catastrophic' COLLAPSE – sparking 9.8ft of irreversible global sea level rise, scientists warn

Daily Mail​

10 hours ago

It is one of the largest ice masses on Earth, covering an area of roughly 760,000 square miles.
But the West Antarctic Ice Sheet is on the verge of a 'catastrophic' collapse, scientists have warned.
As global carbon dioxide (CO2) levels continue to rise, researchers from the Australian National University say that the ice sheet is weakening, and is at increasing risk of collapsing altogether.
If it did collapse, experts predict the West Antarctic Ice Sheet would raise sea levels by more than 9.8ft (three metres).
This would plunge entire coastal cities and communities around the world underwater.
Here in the UK, towns and cities including Hull, Skegness, Middlesbrough, and Newport would be covered in water.
Meanwhile in Europe, much of the Netherlands, as well as Venice, Montpellier, and Gdansk, would be submerged.
'Rapid change has already been detected across Antarctica's ice, oceans and ecosystems, and this is set to worsen with every fraction of a degree of global warming,' said Dr Nerilie Abram, lead author of the study.
In their study, the researchers set out to understand exactly what would happen if the West Antarctic Ice Sheet collapsed.
Worryingly, their analysis indicates that a collapse would result in 'catastrophic consequences for generations to come.'
'The loss of Antarctic sea ice is another abrupt change that has a whole range of knock–on effects, including making the floating ice shelves around Antarctica more susceptible to wave–driven collapse,' Dr Abram explained.
'The decline in Antarctic sea ice and the slowdown of deep circulation in the Southern Ocean are showing worrying signs of being more susceptible to a warming climate than previously thought.
'As sea ice is lost from the ocean surface, it is also changing the amount of solar heat being retained in the climate system, and that is expected to worsen warming in the Antarctic region.
'Other changes to the continent could soon become unstoppable, including the loss of Antarctic ice shelves and vulnerable parts of the Antarctic ice sheet that they hold behind them.'
One of the biggest impacts would be to Antarctica's wildlife and ocean ecosystems, according to Professor Matthew England, co–author of the study.
'The loss of Antarctic sea ice brings heightened extinction risk for emperor penguins, whose chicks depend on a stable sea ice habitat prior to growing their waterproof feathers,' he warned.
'The loss of entire colonies of chicks has been seen right around the Antarctic coast because of early sea ice breakout events, and some colonies have experienced multiple breeding failure events over the last decade.'
Meanwhile, if the scientists' most extreme predictions are right and global sea levels do rise by 9.8ft, hundreds of coastal towns and cities could be plunged underwater.
Climate Central's Coastal Risk Screening Tool shows the areas around the globe that would be worst hit.
To use the tool, simply set the water level at 9.8ft and the areas that would be plunged underwater will appear in red on the map.
Here in the UK, people living on the east coast of England would be worst hit.
Coastal hubs including Hull, Skegness and Grimsby would be plunged underwater, while places as far inland as Peterborough and Lincoln would also become waterlogged.
Further south, swathes of London would be affected.
Several areas on the River Thames gleam red on the map, including Bermondsey, Greenwich, Battersea, and Chelsea.
While the east coast of England would be most affected, several towns and cities on the west coast are also in the firing line, according to Climate Central.
Neighbourhoods on the outskirts of Weston–super–Mare, Newport and Cardiff would all be plunged underwater, alongside parts of Southport and Blackpool.
Residents in Northern Ireland and Scotland can mostly rest easy though, with few areas set to be affected.
Elsewhere in Europe, Climate Central predicts that the entire coast stretching from Calais to south Denmark would be underwater, along with Venice.
Over in the US, several towns and cities in the Southern states would probably be affected.
These include New Orleans in Louisiana, Galveston in Texas and the Everglades in Florida.
The researchers hope the findings will emphasise the urgent need to limit CO2 emissions and curb global warming.
'The only way to avoid further abrupt changes and their far–reaching impacts is to reduce greenhouse gas emissions fast enough to limit global warming to as close to 1.5 degrees Celsius as possible,' Dr Abram said.
'Governments, businesses and communities will need to factor in these abrupt Antarctic changes that are being observed now into future planning for climate change impacts.'
Antarctica's ice sheets contain 70% of world's fresh water - and sea levels would rise by 180ft if it melts
Antarctica holds a huge amount of water.
The three ice sheets that cover the continent contain around 70 per cent of our planet's fresh water - and these are all to warming air and oceans.
If all the ice sheets were to melt due to global warming, Antarctica would raise global sea levels by at least 183ft (56m).
Given their size, even small losses in the ice sheets could have global consequences.
In addition to rising sea levels, meltwater would slow down the world's ocean circulation, while changing wind belts may affect the climate in the southern hemisphere.
In February 2018, Nasa revealed El Niño events cause the Antarctic ice shelf to melt by up to ten inches (25 centimetres) every year.
El Niño and La Niña are separate events that alter the water temperature of the Pacific ocean.
The ocean periodically oscillates between warmer than average during El Niños and cooler than average during La Niñas.
Using Nasa satellite imaging, researchers found that the oceanic phenomena cause Antarctic ice shelves to melt while also increasing snowfall.
In March 2018, it was revealed that more of a giant France-sized glacier in Antarctica is floating on the ocean than previously thought.