Science Current Events | Science News | Brightsurf.com
 

Changing Antarctic waters could trigger steep rise in sea levels

October 01, 2014

Current changes in the ocean around Antarctica are disturbingly close to conditions 14,000 years ago that new research shows may have led to the rapid melting of Antarctic ice and an abrupt 3-4 metre rise in global sea level.

The research published in Nature Communications found that in the past, when ocean temperatures around Antarctica became more layered - with a warm layer of water below a cold surface layer - ice sheets and glaciers melted much faster than when the cool and warm layers mixed more easily.

This defined layering of temperatures is exactly what is happening now around the Antarctic.

"The reason for the layering is that global warming in parts of Antarctica is causing land-based ice to melt, adding massive amounts of freshwater to the ocean surface," said ARC Centre of Excellence for Climate System Science researcher Prof Matthew England an author of the paper.

"At the same time as the surface is cooling, the deeper ocean is warming, which has already accelerated the decline of glaciers on Pine Island and Totten. It appears global warming is replicating conditions that, in the past, triggered significant shifts in the stability of the Antarctic ice sheet."

The modelling shows the last time this occurred, 14,000 years ago, the Antarctic alone contributed 3-4 metres to global sea levels in just a few centuries.

"Our model simulations provide a new mechanism that reconciles geological evidence of past global sea level rise," said researcher UNSW ARC Future Fellow Dr Chris Fogwill.

"The results demonstrate that while Antarctic ice sheets are remote, they may play a far bigger role in driving past and importantly future sea level rise than we previously suspected."

The accelerating melting of land ice into the sea makes the surface of the ocean around Antarctica colder, less salty and more easily frozen, leading to extensive sea ice in some areas. It is one of the reasons ascribed to the increasing trend in sea ice around Antarctica.

To get their results the researchers used sophisticated ice sheet and climate models and verified their results with independent geological observations from the oceans off Antarctica. The geological data clearly showed that when the waters around the Antarctic became more stratified, the ice sheets melted much more quickly.

"The big question is whether the ice sheet will react to these changing ocean conditions as rapidly as it did 14,000 years ago," said lead author Dr Nick Golledge, a senior research fellow at Victoria's Antarctic Research Centre.

"With 10 per cent of the world's population, or 700 million people, living less than 10 metres above present sea level, an additional three metres of sea level rise from the Antarctic alone will have a profound impact on us all."

ARC Centre of Excellence for Climate System Science


Related Antarctic Ice Current Events and Antarctic Ice News Articles


Will more snow over Antarctica offset rising seas? Don't count on it
Many factors related to warming will conspire to raise the planet's oceans over coming decades -- thermal expansion of the world's oceans, melting of snow and ice worldwide, and the collapse of massive ice sheets.

Scientists predict extensive ice loss from huge Antarctic glacier
Current rates of climate change could trigger instability in a major Antarctic glacier, ultimately leading to more than 2m of sea-level rise.

Evidence of repeated rapid retreat of the East Antarctic ice sheet
Research published in the journal Nature on May 19, 2016 has revealed that vast regions of the Totten Glacier in East Antarctica are fundamentally unstable and have contributed significantly to rising sea levels several times in the past.

Scientists track Greenland's ice melt with seismic waves
Researchers from MIT, Princeton University, and elsewhere have developed a new technique to monitor the seasonal changes in Greenland's ice sheet, using seismic vibrations generated by crashing ocean waves.

What lies beneath West Antarctica?
Three recent publications by early career researchers at three different institutions across the country provide the first look into the biogeochemistry, geophysics and geology of Subglacial Lake Whillans, which lies 800 meters (2,600 feet) beneath the West Antarctic Ice Sheet.

New study is 'a leap forward' in our understanding of ice sheet behavior, expert says
In recent years, climate scientists have grown increasingly concerned that massive rivers of ice flowing into the ocean from Greenland and Antarctica could accelerate as the planet warms, leading to a catastrophic collapse of Earth's ice sheets.

Colossal Antarctic ice-shelf collapse followed last ice age
In a new study that provides clues about how Antarctica's nation-sized Ross Ice Shelf might respond to a warming climate, U.S. and Japanese oceanographers have shown that a 100,000-square-mile section of the ice shelf broke apart within 1,500 years during a warming period after the last ice age.

How stable is the West Antarctic Ice Sheet?
A future warming of the Southern Ocean caused by rising greenhouse gas concentrations in the atmosphere may severely disrupt the stability of the West Antarctic Ice Sheet.

Antarctic study identifies melting ice sheet's role in sea level rise
Loss of ice in Antarctica caused by a warming ocean could raise global sea levels by three metres, research suggests.

Syracuse geophysicist questions stability of Antarctic ice sheet
A professor in Syracuse University's College of Arts and Sciences is joining the growing debate over the fate of the world's largest ice sheet, whose sudden melting is sending shockwaves throughout the geophysics community.
More Antarctic Ice Current Events and Antarctic Ice News Articles

Ice Diaries: An Antarctic Memoir

Ice Diaries: An Antarctic Memoir
by Jean McNeil (Author)


What do we stand to lose in a world without ice?

A decade ago, novelist and short story writer Jean McNeil spent a year as writer-in-residence with the British Antarctic Survey, and four months on the world’s most enigmatic continent — Antarctica. Access to the Antarctic remains largely reserved for scientists, and it is the only piece of earth that is nobody’s country. Ice Diaries is the story of McNeil’s years spent in ice, not only in the Antarctic but her subsequent travels to Greenland, Iceland, and Svalbard, culminating in a strange event in Cape Town, South Africa, where she journeyed to make what was to be her final trip to the southernmost continent.

In the spirit of the diaries of Antarctic explorers Robert Falcon Scott and Ernest Shackleton, McNeil mixes...

Antarctic Ice

Antarctic Ice
by Jim Mastro (Author), Norbert Wu (Author)


Antarctica is the coldest place on earth. Ice covers the mountains, the valleys, and even the sea. In this frozen winter world, every creature is waiting for summer to come.

When the sunny days arrive, a burst of new life begins. A mother Weddell seal finds a safe spot on the surface of the ice to have her baby. Nearby, a little Adélie penguin steals rocks from his neighbor to make a nest. A big emperor penguin works hard to find enough food for his newly hatched chick. The young animals must grow quickly, for summer in Antarctica is brief, and all too soon it will be winter once again.


Trapped by the Ice!: Shackleton's Amazing Antarctic Adventure

Trapped by the Ice!: Shackleton's Amazing Antarctic Adventure
by Michael McCurdy (Author), Michael McCurdy (Illustrator)


Describes the events of the 1914 Shackleton Antarctic expedition when, after being trapped in a frozen sea for nine months, the expedition ship, the Endurance, was finally crushed and Shackleton and his men made the very long and perilous journey across ice and stormy seas to reach inhabited land.

Eagle Over the Ice: The U.S. in the Antarctic

Eagle Over the Ice: The U.S. in the Antarctic
by Christopher C. Joyner (Author), Ethel R. Theis (Author)


The sprawling land mass at our globe's southernmost extreme is the remotest, coldest, highest, driest, windiest, least inhabited, and most barren of all the world's continents. It is also the most pristine, and its special geographical and environmental character makes Antarctica important for scientific research and also influences policies intended to regulate and husband its use. This study of America's role in developing an international regime for governance and protection of the Antarctic challenges the traditional assumption that pursuit of a state's national interest is often irreconcilable with the pursuit of global interests. Instead, Christopher C. Joyner and Ethel R. Theis suggest, by investing financial and physical resources in Antarctic research that surpass all other...

Alone on the Ice: The Greatest Survival Story in the History of Exploration

Alone on the Ice: The Greatest Survival Story in the History of Exploration
by David Roberts (Author)


“An important missing story from the heroic age of Antarctic exploration.”―Laurence Gonzales, author of Deep Survival On January 17, 1913, alone and near starvation, Douglas Mawson, leader of the Australasian Antarctic Expedition, was hauling a sledge to get back to base camp. The dogs were gone. Now Mawson himself plunged through a snow bridge, dangling over an abyss by the sledge harness. A line of poetry gave him the will to haul himself back to the surface.

Mawson was sometimes reduced to crawling, and one night he discovered that the soles of his feet had completely detached from the flesh beneath. On February 8, when he staggered back to base, his features unrecognizably skeletal, the first teammate to reach him blurted out, “Which one are you?”

...

An Antarctic Mystery (The Sphinx of the Ice Fields)

An Antarctic Mystery (The Sphinx of the Ice Fields)
by Jules Verne (Author)


The story is set in 1839, eleven years after the events in Arthur Gordon Pym, one year after the publication of that book. The narrator is a wealthy American Jeorling, who has entertained himself with private studies of the wildlife on the Kerguelen Islands and is now looking for a passage back to the USA. Halbrane is one of the first ships to arrive at Kerguelen, and its captain Len Guy somewhat reluctantly agrees to have Jeorling as a passenger as far as Tristan da Cunha. Underway, they meet a stray iceberg with a dead body on it, which turns out to be a sailor from Jane. A note found with him indicates that he and several others including Jane's captain William Guy had survived the assassination attempt at Tsalal and are still alive. Guy, who had talked to Jeorling earlier about the...

Ice: The Antarctic Diary of Charles F. Passel

Ice: The Antarctic Diary of Charles F. Passel
by Charles F Passel (Author)


"I will never speak lightly of an Antarctic winter night again—I have been through one . . . ."In 1939, Admiral Richard E. Byrd led his last expedition to the Ross Ice Shelf on the continent of Antarctica. A 25-year-old geologist named Charles Passel was one of a small crew of men who took part in this mission, which included a year and a half of isolation from the rest of the world except by amateur radio operators.Passel kept a daily diary throughout the expedition. Days began with the cook prying a frozen griddle from a shelf to make breakfast and the men taking half an hour to dress for work outdoors. Engines had to be heated by blow torch, oil froze while it was being changed, and the crew's tractor ran only in reverse. Though he had come for scientific research, Passel faced...

Ice Wreck (A Stepping Stone Book)

Ice Wreck (A Stepping Stone Book)
by Lucille Recht Penner (Author)


A hundred years ago, Ernest Shackleton and his crew set out for the South Pole. They never made it. Within sight of land, the ship ran into dangerous waters filled with chunks of ice. Then the sea froze around them! There was no hope of rescue. Could Shackleton find a way to save himself and his men?
“Well-written and packed with illustrations and photographs, this amazing tale of the will to survive under unthinkable circumstances will amaze kids and keep them glued to every page.”—Dallas Morning News
“Shackleton’s heart-pounding expedition and rescue comes vividly to life in this beginning chapter book.”—Booklist
Lucille Recht Penner is the author of many nonfiction books for kids, including Dinosaur Babies, and Monster Bugs, in Random House’s Step into Reading...

Innocents on the Ice: A Memoir of Antarctic Exploration, 1957

Innocents on the Ice: A Memoir of Antarctic Exploration, 1957
by John C. Behrendt (Author)


"Adventures in the Antarctic only happen when someone makes a mistake.”
—From the Preface In 1956, John C. Behrendt had just earned his master’s degree in geophysics and obtained a position as an assistant seismologist in the International Geophysical Year glaciological program. He sailed from Davisville, Rhode Island to spend eighteen months in Antarctica with the IGY expedition as part of a U.S. Navy-supported scientific expedition to establish Ellsworth Station on the Filchner Ice Shelf. Innocents on the Ice is a memoir based on Behrendt’s handwritten journals, looking back on his daily entries describing his life and activities on the most isolated of the seven U.S. Antarctic stations.
  Nine civilians and thirty Navy men lived beneath the snow...

The National Geographic Magazine / February, 1999. Biodiversity:Taking Stock of Life; Variety of Life; Under Antarctic Ice; Forest Elephants; Diatoms; Ants and Plants

The National Geographic Magazine / February, 1999. Biodiversity:Taking Stock of Life; Variety of Life; Under Antarctic Ice; Forest Elephants; Diatoms; Ants and Plants
by National Geographic Society / Editor-in-Chief: William L. Allen (Author)


Washington, DC: The National Geographic Society, 1999. The February, 1999 issue, Volume 195, No.2. Quarto, wraps, 132 numbered pp. + pages of unpaginated features and ads. As New; pristine, with a tiny ding at spine top, as received (see scan). Removed from its plastic mailing bag to scan and write-up, then placed in sealed storage. Highest grade. See scan. Feature articles: Biodiversity:Taking Stock of Life; The Variety of Life; Under Antarctic Ice; Forest Elephants; Diatoms, Plants With a Touch of Glass; Ants and Plants - A Profitable Partnership. Departments: Millenium Moments; Behind the Scenes; Forum; Geographica; From the Editor; Flashback; On Screen; Earth Almanac; Interactive; On Assignment. L-pr2

© 2017 BrightSurf.com