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





ISAF Sailing Worlds, Santander - Strong competition for RS:X fleets by Olga Maslivets, International RS:X Class Assoc.,


































470 Men and Women Worlds - Game on for Olympic Qualification by 470 International Association Class,












A complete recap of the most successful Melges 20 World Championship by International Audi Melges 20 Class Association,




ISAF Santander - Upwards path for Austrian women's 470 crew + video by Luissa Smith, International 470 Class Association,












ISAF Sailing World Championships - Day 4 images from Santander
ISAF Sailing Worlds, Santander: Emerging Nations Program sailors shine
ISAF Sailing Worlds, Santander - Teasing winds play havoc on day 4
ISAF Sailing World Championships: Hot conditions in Santander on day 4
Santander ISAF Sailing World Championships joins Bart’s Bash
PWA Cold Hawaii World Cup - Grounded fishing boat creates problems
Marseille One Design - GC32 Armin Strom Sailing Team emerge victorious
Rolex Big Boat Series 2014 - Ready for another 50 years
2014 Rolex Big Boat Series - Farr 40 Day 4
2014 Rolex Swan Cup - Eleventh-hour victories
Extreme Sailing Series - Kiwis clinch Act win in Istanbul + Video
2014 Rolex Big Boat Series - Two long races today for the J70 fleet
2014 Rolex Big Boat Series - Impressive to sail out of the Golden Gate
Extreme Sailing Series - Istanbul delivers four days of great racing
ISAF Sailing Worlds Santander - Day 3 images by Sail-World.com
Extreme Sailing Series: Emirates Team NZ bounces back for series win
Santander 2014 ISAF Worlds - Light winds and current test six classes
ISAF Sailing World Championships - Solid Day 3 for US Sailing Team
ISAF Sailing World Championships - Day 3 images by Jesus Renedo
Marseille One Design 2014 - GC32 Armin Strom blitzes final day
Volvo Ocean Race 2014-15 - Una Etapa 0 complicada para todos   
Santander 49ers: Olympic Gold Medallist says two into 90 does not go!! *Feature   
GBR aiming for first ever Nacra 17 Games berth at Santander Worlds   
Volvo Ocean Race: Man and sail overboard as Leg 0 serves up drama   
ISAF Sailing World Championships Santander 2014 – Images by Dan Ibsen   
Santander Worlds – already a spectator success   
ISAF Sailing World Championships Santander 2014 - Day 3 morning report   
Volvo Ocean Race 2014-15 - Tales from the extreme   
Volvo Ocean Race: Latest starter wins opening race   
2014 J/70 World Championship - Healy, Abdullah, Becker and Borges win   
2014 Rolex Big Boat Series - Full-blown, once again   
ISAF Worlds - Americans jump up Laser and Laser Radial leaderboard   
2014 Rolex Big Boat Series - Farr 40 Day 3   
ISAF Sailing World Championships - Day 2 images from Sail-World.com   
America's Cup: Luna Rossa sailing with two foiling AC45's + Video   
Extreme Sailing: Emirates Team NZ retain second overall   
ISAF Sailing Worlds, Santander - Rio Olympic Laser spots snapped up   
Rolex Swan Cup - All set for final showdown   
Upper Midwest sailors need help to take it to the next level   
ISAF Sailing World Championships - RS:X action begins in Santander   


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 NEW US
LocalAds   DE  ES  FR  IT