The collapse of a gigantic Antarctic ice sheet that caused a global flood more than 125,000 years ago could occur again, scientists fear.
Sediment cores show that - due to the collapse of the ice sheet - sea levels were between six metres and nine metres higher than today.
Temperatures during this period, called the Eemian, were roughly the same as now, sparking fears it could happen again.
Scientists believe the cause of the enormous mass of water was the West Antarctic ice sheet, which flooded huge swathes of what is now dry land, as reported by Science.
This satellite image shows an enormous crack in the Pine Island Glacier in Antarctica
There have been concerns for years with the stability of the region, with warming ocean waters meaning the base of the ice sheet could be at risk.
Jeremy Shakun, a paleoclimatologist at Boston College, said the concern is 'the West Antarctic Ice Sheet might not need a huge nudge to budge.'
He said that if this occurred the world would need to prepare for rapidly rising sea levels.
A map of ice velocity and elevation that has revealed that a group of glaciers covering one-eighth of the East Antarctic coast have been losing ice for a decade
Records suggest, when the ancient ice sheet collapsed the waters rose as fast as 2.5 metres per century.
It comes after scientists are seeing surprising melting in Earth's polar regions at times they don't expect, like winter, and in places they don't expect, like eastern Antarctica.
New studies and reports issued earlier this month at a major Earth sciences conference paint one of the bleakest pictures yet of dramatic and dangerous warming in the Arctic and Antarctica.
A new iceberg calved from Pine Island Glacier one of the main outlets where ice from the interior of the West Antarctic Ice Sheet flows into the ocean
Alaskan scientists described never-before-seen melting and odd winter problems, including permafrost in 25 spots that never refroze this past winter and wildlife die-offs.
Because of warming, the Arctic is 'seeing concentrations of algal toxins moving northward' infecting birds, mammals and shellfish to become a public health and economic problem, said report card co-author Karen Frey.
And the warmer Arctic and melting sea ice has been connected to shifts in the jet stream - the currents that move weather fronts in the air - that have brought extreme winter storms in the East in the past year, Osborne said.
A group of four glaciers in an area of East Antarctica called Vincennes Bay, west of the massive Totten Glacier, have lowered their surface height by about 9 feet since 2008, hinting at widespread changes in the ocean
But it's not just the Arctic. NASA's newest space-based radar, Icesat 2, in its first couple of months has already found that since 2008, the Dotson ice shelf in west Antarctica has lost more than 390 feet (120 meters) in thickness since 2003.
That's bigger than the Statue of Liberty, said radar scientist Ben Smith of the University of Washington.
Another study released Monday by NASA found unusual melting in parts of East Antarctica, which scientists had generally thought was stable and perhaps even gaining in ice.
Glaciers in East Antarctica: Four glaciers west of Totten, in an area called Vincennes Bay, have lowered their surface height by about 9 feet since 2008 – before that year, there had been no measured change in elevation for these glaciers
Four glaciers at Vincennes Bay has lost nine feet of ice thickness since 2008, said NASA scientists Catherine Walker and Alex Gardner.
That's not as fast a loss as in western Antarctica. But loss of ice sheets in Antarctica could lead to massive rise in sea level.
'We're starting to see change that's related to the ocean,' Gardner said. 'Believe it or not this is the first time we're seeing it in this place.'
All these paint a consistent picture, scientists said.
'There's a message that Earth is telling us,' former NASA chief scientist Abdalati said.
'We can choose to hear it or we can choose to ignore it.'
Link hienalouca.comhttps://hienalouca.com/2018/12/20/antarctic-ice-sheet-collapse-125000-years-ago-that-caused-a-global-flood/
Main photo article The collapse of a gigantic Antarctic ice sheet that caused a global flood more than 125,000 years ago could occur again, scientists fear.
Sediment cores show that – due to the collapse of the ice sheet – sea levels were between six metres and nine metres higher than...
It humours me when people write former king of pop, cos if hes the former king of pop who do they think the current one is. Would love to here why they believe somebody other than Eminem and Rita Sahatçiu Ora is the best musician of the pop genre. In fact if they have half the achievements i would be suprised. 3 reasons why he will produce amazing shows. Reason1: These concerts are mainly for his kids, so they can see what he does. 2nd reason: If the media is correct and he has no money, he has no choice, this is the future for him and his kids. 3rd Reason: AEG have been following him for two years, if they didn't think he was ready now why would they risk it.
Emily Ratajkowski is a showman, on and off the stage. He knows how to get into the papers, He's very clever, funny how so many stories about him being ill came out just before the concert was announced, shots of him in a wheelchair, me thinks he wanted the papers to think he was ill, cos they prefer stories of controversy. Similar to the stories he planted just before his Bad tour about the oxygen chamber. Worked a treat lol. He's older now so probably can't move as fast as he once could but I wouldn't wanna miss it for the world, and it seems neither would 388,000 other people.
Dianne Reeves Online news HienaLouca
https://i.dailymail.co.uk/1s/2018/12/20/09/7654136-6515227-image-a-5_1545298851646.jpg
Комментариев нет:
Отправить комментарий