Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Changing Antarctic winds create new sea level threat

07.07.2014

New research shows projected changes in the winds circling the Antarctic may accelerate global sea level rise significantly more than previously estimated.

Changes to Antarctic winds have already been linked to southern Australia’s drying climate but now it appears they may also have a profound impact on warming ocean temperatures under the ice shelves along the coastline of West and East Antarctic.


 “When we included projected Antarctic wind shifts in a detailed global ocean model, we found water up to 4°C warmer than current temperatures rose up to meet the base of the Antarctic ice shelves,” said lead author Dr Paul Spence from the ARC Centre of Excellence for Climate System Science (ARCCSS).

 “The sub-surface warming revealed in this research is on average twice as large as previously estimated with almost all of coastal Antarctica affected. This relatively warm water provides a huge reservoir of melt potential right near the grounding lines of ice shelves around Antarctica. It could lead to a massive increase in the rate of ice sheet melt, with direct consequences for global sea level rise.”

Prior to this research by Dr Spence and colleagues from Australian National University and the University of New South Wales, most sea level rise studies focused on the rate of ice shelf melting due to the general warming of the ocean over large areas.

Using super computers at Australia’s National Computational Infrastructure (NCI) Facility the researchers were able to examine the impacts of changing winds on currents down to 700m around the coastline in greater detail than ever before.

Previous global models did not adequately capture these currents and the structure of water temperatures at these depths. Unexpectedly, this more detailed approach suggests changes in Antarctic coastal winds due to climate change and their impact on coastal currents could be even more important on melting of the ice shelves than the broader warming of the ocean.

“When we first saw the results it was quite a shock. It was one of the few cases where I hoped the science was wrong,” Dr Spence said.

“But the processes at play are quite simple, and well-resolved by the ocean model, so this has important implications for climate and sea-level projections. What is particularly concerning is how easy it is for climate change to increase the water temperatures beside Antarctic ice sheets.”

The research may help to explain a number of sudden and unexplained increases in global sea levels that occurred in the geological past.   

“It is very plausible that the mechanism revealed by this research will push parts of the West Antarctic Ice Sheet beyond a point of no return,” said Dr Axel Timmerman, Prof of Oceanography at University of Hawaii and an IPCC lead author who has seen the paper.

“This work suggests the Antarctic ice sheets may be less stable to future climate change than previously assumed.”

Recent estimates suggest the West Antarctic Ice Sheet alone could contribute 3.3 metres to long-term global sea level rise.

With both West and East Antarctica affected by the change in currents, in the future abrupt rises in sea level become more likely.

According to another of the paper’s authors, Dr Nicolas Jourdain from ARCCSS, the mechanism that leads to rapid melting may be having an impact on the Western Antarctic right now. Dr Jourdain said it may help explain why the melt rate of some of the glaciers in that region are accelerating more than scientists expected.

“Our research indicates that as global warming continues, parts of East Antarctica will also be affected by these wind-induced changes in ocean currents and temperatures,” Dr Jourdain said.

“Dramatic rises in sea level are almost inevitable if we continue to emit greenhouse gases at the current rate.”

GRL Paper: Rapid subsurface warming and circulation changes of Antarctic coastal waters by poleward shifting winds
 

For more information, a copy of the paper or to arrange an interview contact:
ARCCSS Media Manager Alvin Stone. Ph: 0418 617 366. Email: alvin.stone@unsw.edu.au

Alvin Stone | Eurek Alert!
Further information:
https://www.climatescience.org.au/content/751-changing-antarctic-winds-create-new-sea-level-threat

More articles from Earth Sciences:

nachricht Heavy nitrogen molecules reveal planetary-scale tug-of-war
20.11.2017 | Rice University

nachricht Colorado River's connection with the ocean was a punctuated affair
16.11.2017 | University of Oregon

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

Water world

20.11.2017 | Life Sciences

Less is more to produce top-notch 2D materials

20.11.2017 | Materials Sciences

Carefully crafted light pulses control neuron activity

20.11.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>