Free Newsletters - Space News - Defense Alert - Environment Report - Energy Monitor
. Earth Science News .




ICE WORLD
East Antarctic Ice Sheet could be more vulnerable to climate change than previously thought
by Staff Writers
Durham, UK (SPX) Sep 05, 2013


Current scientific opinion suggests that glaciers in East Antarctica are at less risk from climate change than areas such as Greenland or West Antarctica due to its extremely cold temperatures which can fall below minus 30 C at the coast, and much colder further inland.

The world's largest ice sheet could be more vulnerable to the effects of climate change than previously thought, according to new research from Durham University.

A team from the Department of Geography used declassified spy satellite imagery to create the first long-term record of changes in the terminus of outlet glaciers - where they meet the sea - along 5,400km of the East Antarctic Ice Sheet's coastline. The imagery covered almost half a century from 1963 to 2012.

Using measurements from 175 glaciers, the researchers were able to show that the glaciers underwent rapid and synchronised periods of advance and retreat which coincided with cooling and warming.

The researchers said this suggested that large parts of the ice sheet, which reaches thicknesses of more than 4km, could be more susceptible to changes in air temperatures and sea-ice than was originally believed.

Current scientific opinion suggests that glaciers in East Antarctica are at less risk from climate change than areas such as Greenland or West Antarctica due to its extremely cold temperatures which can fall below minus 30 C at the coast, and much colder further inland.

But the Durham team said there was now an urgent need to understand the vulnerability of the East Antarctic Ice Sheet, which holds the vast majority of the world's ice and enough to raise global sea levels by over 50m.

The findings are published in the prestigious scientific journal Nature.

Dr Chris Stokes, in Durham's Department of Geography, said: "We know that these large glaciers undergo cycles of advance and retreat that are triggered by large icebergs breaking off at the terminus, but this can happen independently from climate change.

"It was a big surprise therefore to see rapid and synchronous changes in advance and retreat, but it made perfect sense when we looked at the climate and sea-ice data.

"When it was warm and the sea-ice decreased, most glaciers retreated, but when it was cooler and the sea ice increased, the glaciers advanced.

"In many ways, these measurements of terminus change are like canaries in a mine - they don't give us all the information we would like, but they are worth taking notice of."

The researchers found that despite large fluctuations in terminus positions between glaciers - linked to their size - three significant patterns emerged:

+ In the 1970s and 80s, temperatures were rising and most glaciers retreated;

+ During the 1990s, temperatures decreased and most glaciers advanced;

+ And the 2000s saw temperatures increase and then decrease, leading to a more even mix of retreat and advance.

Trends in temperature and glacier change were statistically significant along the East Antarctic Ice Sheet's warmer Pacific Coast, but no significant changes were found along the much cooler Ross Sea Coast, which might be expected if climate is driving the changes, the Durham researchers said.

Dr Stokes said that the cause of the recent trends in air temperature and sea ice were difficult to unravel but were likely to reflect a combination of both natural variability and human impacts.

However, he added that the changes observed in glaciers in East Antarctica needed further investigation against the backdrop of likely increases in both atmospheric and ocean temperatures caused by climate change.

Dr Stokes said: "If the climate is going to warm in the future, our study shows that large parts of the margins of the East Antarctic Ice Sheet are vulnerable to the kinds of changes that are worrying us in Greenland and West Antarctica - acceleration, thinning and retreat.

"When temperatures warm in the air or ocean, glaciers respond by retreating and this can have knock-on effects further inland, where more and more ice is drawn-down towards the coast.

"We need to monitor their behaviour more closely and maybe reassess our rather conservative predictions of future ice sheet dynamics in East Antarctica."

.


Related Links
Durham University
Beyond the Ice Age






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

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




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News





ICE WORLD
Change of Venue for NASA's IceBridge Antarctic Operations
Greenbelt MD (SPX) Aug 26, 2013
This fall, NASA's Operation IceBridge will base its annual Antarctic campaign out of National Science Foundation's McMurdo Station, a change from the mission's previous four campaigns that were based in Punta Arenas, Chile. By switching bases of operations, IceBridge will be able to expand its reach by measuring parts of Antarctica previously unavailable to the mission. "Antarctica is a bi ... read more


ICE WORLD
Niger asks for foreign help for flood victims

Olympics: Tokyo 2020 is a bid in the shadow of Fukushima

Italy says Syria crisis to worsen refugee problem

Australian police arrest suspected people smugglers

ICE WORLD
World's First Full Color 3D Desktop Printer Destined For High Schools

Lockheed Martin-Built A2100 Satellites: Over 400 Cumulative Years In Orbit And Counting

GSAT-7 Satellite Placed in Geosynchronous Orbit

A completely new atomic crystal dynamic of the white pigment titanium dioxide discovered

ICE WORLD
Submarine canyons a source of marine invertebrate diversity, abundance

Morphing manganese

Ocean fish acquire more mercury at depth

Sea otters promote recovery of seagrass beds

ICE WORLD
East Antarctic Ice Sheet could be more vulnerable to climate change than previously thought

On warming Antarctic Peninsula, moss and microbes reveal unprecedented ecological change

Arctic Sea Ice Update: Unlikely To Break Records, But Continuing Downward Trend

West Antarctica ice sheet existed 20 million years earlier than previously thought

ICE WORLD
Chinese dairies seek French tie-ups to shore up image

Peking duck not all it's quacked up to be

Crop pests moving polewards through global warming

New Zealand wants answers on milk 'botulism botch-up'

ICE WORLD
Vietnam flood toll hits 21

Supervolcanic Ash Can Turn To Lava Miles From Eruption, MU Scientists Find

Tropical Storm Lorena lashes Mexico Pacific coast

6.0 magnitude quake strikes off northern Philippines

ICE WORLD
Origin of state of ancient Egypt given new time line

Defence chiefs meet over DR Congo conflict

Kenyan soldiers kill al-Shabaab guerillas

Kenya looks east, signs $5-bn China deals

ICE WORLD
Researchers reveal hunter-gatherers' taste for spice

Building better brain implants: The challenge of longevity

Researchers say human foot not unique, more like those of great apes

Archaeologists find evidence of separate Neanderthal cultures in Europe




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal 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. 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. Privacy Statement