. 24/7 Space News .
ICE WORLD
Antarctica to lift seas by metres per degree of warming: study
By Marlowe HOOD
Paris (AFP) Sept 23, 2020

Raising Earth's average surface temperature another degree Celsius will lock in 2.5 metres of sea level rise from Antarctica alone and an extra three degrees see the frozen continent lift oceans 6.5 metres, scientists warned Wednesday.

These devastating increases in the global waterline -- enough to cripple coastal cities from Mumbai to Miami and displace hundreds of millions of people -- would unfold over hundreds to thousands of years.

But the man-made greenhouse gas emissions that could guarantee such an outcome are on track to occur on a timescale measured in decades, they reported in the journal Nature.

One of the study's most alarming conclusions is that hikes in sea level caused by a disintegrating Antarctic ice sheet -- which holds enough frozen water to boost oceans 58 metres -- would become dramatically larger with each additional degree of warming.

Sea level rise, for example, would average about 1.3 metres (four feet) for each of the first two degrees above pre-industrial levels.

Earth's average surface temperature has already gone up one degree since the late 19th century, enough to enhance the severity of deadly heatwaves, droughts and tropical cyclones.

But from 2C to 6C above that benchmark, the increase in sea level would double to 2.4 metres per degree of warming.

At the upper end of that range, climate change would devastate civilisation and redraw the map of the world's coastlines, scientists say.

Beyond that, each added degree would result in 10 more metres, pushing the entire ice sheet past the point of no return and lifting oceans to levels not seen for millions of years.

"In the end, it is our burning of coal and oil that determines if and when critical temperature thresholds in Antarctica are crossed," co-author Anders Levermann, a climate scientist at the Potsdam Institute for Climate Impact Research, said in a statement.

- An 'existential threat' -

"And even if the ice loss happens on long time scales, the respective carbon dioxide levels can already be reached in the near future."

The ice sheet atop West Antarctica will be the first to go, eroded not so much by warm air but rather warm sea water seeping below the underbelly of glaciers and eroding their ocean-facing edges, known as ice shelves.

"That makes glaciers the size of Florida slide into the ocean," noted co-author Torsten Albrecht, also a researcher at the Potsdam Institute.

Once global warming crosses the 6C threshold, the dynamic changes.

"As the gigantic mountains of ice" -- up to five kilometres thick -- "slowly sink to lower heights where the air is warmer, this leads to more melt at the ice surface," Albrecht added.

This process has already created raging rivers of meltwater on the Greenland ice sheet, which saw a net loss of more than half-a-trillion tonnes in mass last year alone.

"This very important and timely study makes clear the urgent need to stabilise surface temperature rise in line with Paris Agreement targets so as to limit the total committed sea level rise to a few metres," said Matt Palmer, a UK Met Office sea level rise scientist who did not take part in the research.

The 2015 treaty enjoins nations to cap global warming at "well below" 2C, and 1.5C if possible.

Even a 2C world "represents an existential threat to entire nation states," Jonathan Bamber, a glaciology professor at the University of Bristol, told the Science Media Centre, commenting on the study.

"We're looking at removing nations from the map -- it doesn't get much more serious than that."


Related Links
Beyond the Ice Age


Thanks for being there;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceDaily Monthly Supporter
$5+ Billed Monthly


paypal only
SpaceDaily Contributor
$5 Billed Once


credit card or paypal


ICE WORLD
Antarctica: cracks in the ice
Delft, Netherlands (SPX) Sep 15, 2020
In recent years, the Pine Island Glacier and the Thwaites Glacier on West-Antarctica has been undergoing rapid changes, with potentially major consequences for rising sea levels. However, the processes that underlie these changes and their precise impact on the weakening of these ice sheets have not yet been fully charted. A team of researchers including some from TU Delft have now investigated one of these processes in detail: the emergence and development of damage/cracks in part of the glaciers ... read more

Comment using your Disqus, Facebook, Google or Twitter login.



Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle

ICE WORLD
Trump tech war with China changes the game for US business

Small leak of ammonia detected at US Segment of ISS

NASA's Partnership Between Art and Science: A Collaboration to Cherish

Israeli tech start-ups take on the Emirates

ICE WORLD
Hardware testing heats up at Marshall test lab

NASA technology enables precision landing without a pilot

UK Spaceports form historic alliance

PLD Space closes new investment in tie-up with Arcano Partners

ICE WORLD
Study shows difficulty in finding evidence of life on Mars

AFRL technology traveling to Mars

Using chitin to manufacture tools and shelters on Mars

China's Mars probe travels 137 mln km

ICE WORLD
China sends nine satellites into orbit by sea launch

Chinese spacecraft launched mystery object into space before returning to Earth

China's reusable spacecraft returns to Earth after 2 days

Mars-bound Tianwen 1 hits milestone

ICE WORLD
ESA brings space industry together online

SpaceX postpones Starlink launch from Florida

Dragonfly Aerospace emerges from SCS Aerospace Group

COMSAT expands hardware footprint with new Orbit Communications Systems agreement

ICE WORLD
Marine sponges inspire the next generation of skyscrapers and bridges

Squeezed light makes Virgo's mirrors jitter

Could PlayStation 5 and Xbox Series X be swan song for consoles?

Chromium steel was first made in ancient Persia

ICE WORLD
Evolution of radio-resistance is more complicated than previously thought

How protoplanetary rings form in primordial gas clouds

Venus is one stop in our search for life

A white dwarf's surprise planetary companion

ICE WORLD
Astronomers characterize Uranian moons using new imaging analysis

Jupiter's moons could be warming each other

Atomistic modelling probes the behavior of matter at the center of Jupiter

Technology ready to explore subsurface oceans on Ganymede









The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us.