sail-world.com
 
 
News Home Video Gallery Photo Gallery
Sail-World.com : Planning a sail to the Antarctic any time soon? - check this out!
Planning a sail to the Antarctic any time soon? - check this out!


'Antarctic sea ice'    . ©    Click Here to view large photo

While global warming may be making it easier to sail the Northwest Passage and in Arctic regions generally, the same global warming might, paradoxically, make it more difficult to sail in Antarctic regions.

In an apparent polar paradox, global warming has led to more ice in the sea around Antarctica and could help insulate the southern hemisphere from atmospheric warming.


A Dutch study says that unlike in the Arctic region, sea ice around Antarctica has expanded at a significant rate since 1985.

Scientists have known for several years that meltwater from ice sheets can form a cold, fresh layer on the ocean surface that protects sea ice from the warmer waters below. But they were not sure whether that aided the observed expansion of Antarctic sea ice as the new study suggests.

Published online in Nature Geoscience, the article suggests cool freshwater from melt beneath the Antarctic ice shelves has insulated offshore sea ice from the warming ocean beneath.

Richard Bintanja of the Royal Netherlands Meteorological Institute and colleagues say the Antarctic sea ice expands during southern hemisphere autumn and winter in response to this fresh, cool surface layer that freezes easily.

'Against the background of global climate warming, the expansion of Antarctic sea ice is an exceptional feature, which seems to be associated with decreasing sea surface temperatures in the Southern Ocean,' they write.

'We predict that this mechanism will be a sizable contributor to the factors that regionally and seasonally offset greenhouse warming and the associated sea ice retreat.'

They say the expanding sea ice may constitute a 'feedback' that has the potential to oppose southern hemisphere atmospheric warming and amplify increases in global sea level.

Changes in sea ice can significantly modulate climate change because of its high reflective and strong insulating nature, the paper says.

There are other plausible explanations for Antarctic sea-ice expansion, however.

'The mechanism could be completely true, but this study does not demonstrate that increased melting has made a significant contribution to the increase in sea-ice cover,' says Paul Holland, an ocean modeller at the British Antarctic Survey in Cambridge, UK, who last year co-authored a study showing that the sea-ice expansion is caused in large part by regional wind patterns.

Winds change the extent of sea ice, both by physically moving the ice and by warming or cooling the sea surface. Using satellite data for sea-ice motion in 1992–2010, Holland and his colleague Ron Kwok, a climate researcher at NASA's Jet Propulsion Laboratory in Pasadena, California, showed that in certain regions of Antarctica, such as the Weddell Sea, sea-ice changes are almost entirely due to the physical force of the winds. In other areas, such as the King Håkon Sea, they result from the combined effects of wind force and temperature.

Bintanja says that wind effects are important locally but that meltwater influences sea-ice expansion regionally. Holland counters that ice melt is not uniform around the Antarctic coastline — as assumed by the authors of the latest study — but is concentrated in certain locations. Holland says that both wind patterns and meltwater may be expanding the sea-ice near the South Pole, but that remains to be seen.

More at http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo1767.html


by Media Services

  

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

http://www.sail-world.com/index.cfm?nid=107995

6:17 AM Mon 1 Apr 2013GMT


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







News - USA and the World

Rolex China Sea Race 2014 - nip and tuck for IRC honours by RHKYC and Guy Nowell, Sail-World Asia, Hong Kong


America's Cup Book Review: Winging It - Oracle Team USA's comeback *Feature by Richard Gladwell Sail-World.com/nz,


























HUD Vision: An interview with Afterguard Marine’s Alex Moret *Feature by David Schmidt, Sail-World USA Editor, Seattle














America's Cup: Expected de Ridder penalty should be reduced *Feature by Richard Gladwell/Sail-World.com/nz, Auckland, NZ
















Congressional Cup - Victory for Taylor Canfield and crew by Rich Roberts (As Amended by ISAF),




2014 Halifax – Saint-Pierre Ocean Race by Patricia Nelder, Nova Scotia




WWA Pro Card Qualifier - Pro Cards earned at Freedom Wake Park
Christmas Caribbean Rally - Top class sailors to compete
Earth Day boater tips
Anna Tunnicliffe - from CrossFit to Extreme 40's
Charleston Race Week - Photos by Chris Howell
Image Gallery: Stratis SL33 flies on the Waitemata
Audi Melges 20- Sperry Topsider Charleston Race Week - Light final day
Clipper Round the World Yacht Race - PSP Logistics prepares for USA
ISAF Sailing World Cup Hyères - Crème of the crop to compete
Congressional Cup: Luna Rossa makes podium in first event
Int 14 World Championships 2015 launch new event website
International Optimist Regatta Clinic and Team Race - Register now!
Congressional Cup: World top rankers finish that way in Long Beach
Sperry Top-Sider Charleston Race Week Day 3 finale
America's Cup: Gino Morrelli outlines the new AC62 design
Doyle Sails New Zealand signs Andrew Brown as One Design Manager
America's Cup: Dean Barker's Blog - A sail with the Duke and Duchess *Feature
29er World Youth Sailing Week Easter regatta - Day 1 and 2 overall
C Thomas Clagett Jr Memorial Clinic/Regatta - Entries start to roll in
50th Congressional Cup: See the delayed coverage and media conferences
Clipper Race 10 Day 27: Closing stages - Qingdao to San Francisco   
Canfield, Williams, Bruni, Swinton in Congressional Cup final four   
Sperry Top-Sider Charleston Race Week - Day 2   
Audi Melges 20 Charleston Race Week - Perfect conditions in Charleston   
Oyster Regatta Antigua - Full on ocean conditions for day 3   
PWA World Tour - A taste of things to come at La Torche + Video   
Women's International Match Racing Series kicks off in June   
Melges 32 Audi Tron Sailing Series - Action shots by Max Ranchi   
Clipper Round the World Yacht Race - Frustrating conditions   
Man rescued after falling overboard in Pacific taken to hospital   
Sperry Top-Sider Charleston Race Week 2014 - Youth leading Melges 20   
Congressional Cup - Canfield leads toward Congressional Cup sailoffs   
Sperry Top-Sider Charleston Race Week 2014 - Perfection for Day 1   
America's Cup: Coutts claims ISAF Jury on a crusade, backs Kiwi report *Feature   
Clipper Round the World Yacht Race - Will light winds hamper progress?   
Les Voiles de St. Barth - Preparing to rock Saint Barthélemy waters   
Clipper Round the World Race - OneDLL and Qingdao now in San Francisco   
America's Cup: Emirates Team NZ up against funding hurdle for year *Feature   
Melges 32 Sailing Series Napoli - Day 1 images by Stefano Gattini   
50th Congressional Cup: View the Live racing here   


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.
X6XL NEW US