sail-world.com
 
 
News Home Cruising Photo Gallery Video Gallery
Sail-World.com : Antarctic sea ice cover increases under the effects of climate change
Antarctic sea ice cover increases under the effects of climate change

'Sea ice around Antarctica'    British Antarctic Survey ©

The first direct evidence that marked changes to Antarctic sea ice drift have occurred over the last twenty years, in response to changing winds, is published this week in the journal Nature Geoscience. Scientists from NERC’s British Antarctic Survey (BAS) and NASA’s Jet Propulsion Laboratory (JPL), Pasadena California explain why, unlike the dramatic losses reported in the Arctic, the Antarctic sea ice cover has increased under the effects of climate change.

Maps created by JPL using over five million individual daily ice motion measurements captured over a period of 19 years by four US Defense Meteorological satellites show, for the first time, the long-term changes in sea ice drift around Antarctica.

Lead author, Dr. Paul Holland of BAS says: 'Until now these changes in ice drift were only speculated upon, using computer models of Antarctic winds. This study of direct satellite observations shows the complexity of climate change. The total Antarctic sea-ice cover is increasing slowly, but individual regions are actually experiencing much larger gains and losses that are almost offsetting each other overall. We now know that these regional changes are caused by changes in the winds, which in turn affect the ice cover through changes in both ice drift and air temperature. The changes in ice drift also suggest large changes in the ocean surrounding Antarctica, which is very sensitive to the cold and salty water produced by sea-ice growth.

Dr Paul Holland - Ocean Modeller at British Antarctic Survey -  British Antarctic Survey ©  
'Sea ice is constantly on the move; around Antarctica the ice is blown away from the continent by strong northward winds. Since 1992 this ice drift has changed. In some areas the export of ice away from Antarctica has doubled, while in others it has decreased significantly.'

Sea ice plays a key role in the global environment — reflecting heat from the sun and providing a habitat for marine life. At both poles sea ice cover is at its minimum during late summer. However, during the winter freeze in Antarctica this ice cover expands to an area roughly twice the size of Europe. Ranging in thickness from less than a metre to several metres, the ice insulates the warm ocean from the frigid atmosphere above.

The new research also helps explain why observed changes in the amount of sea-ice cover are so different in the two Polar Regions. The Arctic has experienced dramatic ice losses in recent decades while the overall ice extent in the Antarctic has increased slightly. However, this small Antarctic increase is actually the result of much larger regional increases and decreases, which are now shown to be caused by wind-driven changes. In places, increased northward winds have caused the sea-ice cover to expand outwards from Antarctica. The Arctic Ocean is surrounded by land, so changed winds cannot cause Arctic ice to expand in the same way.

Dr. Ron Kwok, JPL says, 'The Antarctic sea ice cover interacts with the global climate system very differently than that of the Arctic, and these results highlight the sensitivity of the Antarctic ice coverage to changes in the strength of the winds around the continent.'

There has been contrasting climate change observed across the Antarctic in recent decades. The Antarctic Peninsula has warmed as much as anywhere in the Southern Hemisphere, while East Antarctica has shown little change or even a small cooling around the coast. The new research improves understanding of present and future climate change. It is important to distinguish between the Antarctic Ice Sheet — glacial ice — which is losing volume, and Antarctic sea ice — frozen seawater — which is expanding.

This research was funded by the Natural Environment Research Council (NERC) and National Aeronautics and Space Administration (NASA).

British Antarctic Survey website


by British Antarctic Survey

  

Click on the FB Like link to post this story to your FB wall

http://www.sail-world.com/index.cfm?nid=103823

6:49 PM Thu 15 Nov 2012GMT


Click here for printer friendly version
Click here to send us feedback or comments about this story.







News - USA and the World









Volvo Ocean Race 2014-15 CEO Knut Frostad talks (Part III) *Feature by Rob Kothe and the Sail-World team,


Audi Melges 20 World Championship - ‘Samba Pa Ti’ crowned champion by International Audi Melges 20 Class Association,










Audi Melges 20 World Championship - Final race to decide champion by International Audi Melges 20 Class Association,










Fort Lauderdale International Boat Show - 13 things to See and do by Fort Lauderdale International Boat Show,




Volvo Ocean Race: Update from Team Vestas Wind in images by Richard Gladwell/Sail-World.com/nz,








Audi Melges 20 World Championship - Classic Garda conditions on day 2 by International Audi Melges 20 Class Association,
























Audi Melges 20 World Championship - Alessandro Rombelli's 'STIG' leads
Volvo Ocean Race: Call of Duty comes first for Team Alvimedica
Audi Melges 20 World Championship - Day 1 images by Stefano Gattini
Helping boaters understand weather basics
PWA Alacati World Cup - Exciting finish on day 2
Match 40s find the surface again + Video
Audi Melges 20 World Championship - Day 1 images by Max Ranchi
Clagett Regatta names first Executive Director
Transatlantic Race - Fleet expanded for 2015 edition
IFDS World Championship overall
Anna Tunnicliffe: Alinghi finishes second - Extreme Sailing Series
2014 18' Skiff International Regatta - Day 2
2014 Audi Melges 20 World Championship - It's go time in Garda
2nd Annual Keith Dinsmoor Regatta September 13-14
Aldo Alessio Regatta - Three days of tight racing
PWA Alacati World Cup - First blood to Van Der Steen and Offringa
Oakcliff Sailing hosts the Nacra 17, 49er and 49erFX Nationals + Video
International 18ft Skiff Regatta underway on San Francisco Bay
Maxi Yacht Rolex Cup 2014 - Quality fleet for Maxi Classic
Sailing Champions League - which is Europe's best sailing club?
Weta fun at the Wine & Roses Regatta   
Extreme Sailing Series: The Wave, Muscat claims victory on Cardiff Bay   
International 14 World Championships 2015: Not just for boys   
Rio de Janeiro achieves 50% treatment of sewage outflow *Feature   
2014 AWT Quatro Desert Showdown - Event memorable videos   
2014 18' Skiff Int Regatta: Day 1 at San Francisco - Reversal on beach   
Emirates Team NZ: Last race boost cannot save team from table bottom   
PWA Alacati World Cup - Furious slalom is upon us   
J/111 World Championships - The Winner is Shmokin Joe!   
J/24 US National Championship - Victory for Will Welles’ Cougar   
Extreme Sailing Series: View the Final Day's action - Replay   
NYYC Grandmasters Team Race - Reign continues for Noroton Yacht Club   
WSSR announces new World Record Around Britain and Ireland   
IFDS Worlds 2014 - Final day photos by Tim Wilkes   
2014 Detroit Cup - Morvan wins   
Newport Bucket Regatta 2014 -Images by George Bekris   
IFDS Worlds 2014 - Final report: USA qualifies for Rio 2016   
Extreme Sailing Series: Absent With-Out Leave – Ben Ainslie Racing   
2014 IFDS World Championship - New champions claim medals   
2014 IFDS World Championships - Sunday’s race images by Tim Wilkes   


For this week's complete news stories select    Last 7 Days
   Search All News
For last month's complete news stories select    Last 30 Days
   Archive News







Sail-World.com  


















Switch Default Region to:

Social Media

Asia

Australia

Canada

Europe

New Zealand

United Kingdom


http://www.sail-world.com/event_images/image/Twitter_logo_small.png http://www.sail-world.com/event_images/image/FaceBook-icon.png  http://www.sail-world.com/event_images/image/RSS-Icon.png

United States

Cruising Northern

Cruising Southern

MarineBusiness World

PowerBoat World

FishingBoating World

 

Contact

Commercial

News

Search

Contact Us

Advertisers Information

Submit news/events

Search Stories/Text

Feedback

Advertisers Directory

Newsletter Archive

Photo Gallery

 

Banner Advertising Details

Newsletter Subscribe

Video Gallery

Policies

 

 

 

Privacy Policy

 

 


Cookie Policy

 

 



This site and its contents are © Copyright TetraMedia and/or the original author, photographer etc. All Rights Reserved.  Photographs are copyright by law.  If you wish to use or buy a photograph contact the photographer directly.
XLXL VIR US
LocalAds   DE  ES  FR  IT