> Powerboat-World.com
 
 
News Home Video Gallery Newsletters FishingBoating Features Photo Gallery Sail-World Australia Australian Cruising
MarineBusiness-World
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.powerboat-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.







Power Boat News























Yamaha inspires students to succeed by Yamaha Motor Australia,








Swan celebrates sales success *Feature by Jeni Bone,




Polar research: Six priorities for Antarctic science by Mahlon C. Kennicutt II and colleagues,


Stealth i14 out of China by Neil Patchett,






























2014 Auckland on the Water Boatshow - Huge prize packs up for grabs
4X4 Outdoors Show and Fishing and Boating Expo wows water lovers
John Wilson has sights set on second P1 SuperStock title
Torquay Grand Prix - Pertemps tops table on penultimate day
Plain sailing for yachts with river cargo ship ban in Shanghai
Dangerous conditions for boaters from this afternoon
Sydney Int'l Boat Show - Stellar results for Multihull Solutions
NSW Environment Minister awards 'Fish Friendly' Marina Accreditations
Refurbished Protector project 'better than buying new'
Gold Coast International Marine Expo - High-Diver Steve Black is back
4x4 Outdoors Show, Fishing and Boating Expo - Campfire cooking corner
See the heat with FLIR ONE *Feature
John Temple to retire, Will Sangster appointed General Manager
Multihull Central launches Aquila range at SIBS *Feature
If all else fails read the instructions!!
If all else fails read the instructions!!
Sun shines on recreational boating at Sydney International Boat Show
Phuket Yacht Show: new kid on the block taking on PIMEX? *Feature
2014 Offshore Superboat Championships - The boats are back!
Sydney International Boat Show - Days 3 & 4 *Feature
Kirby Marine launch 13metre Naiad Tender   
Shellfish reefs in Port Phillip Bay to be rejuvenated   
2014 Brisbane Boat Show - What's your trailer boat worth?   
Custom exhaust system solves buoyancy problem   
Sydney International Boat Show - Day 2 *Feature   
Marine Rescue volunteers celebrate new unit and $120,000 vessel   
Sydney International Boat Show - images from Day 1 *Feature   
Pantaenius Insurance - being seen in yellow, green and orange *Feature   
Sydney International Boat Show begins!   
Sydney International Boat Show - Changed conditions on Sydney Harbour   
Fraser Island annual fishing closure starts August 1   
Mildura boaters reminded Murray River will be low until mid August   
Gold Coast Broadwater no closer to welcoming supermaxis *Feature   
Sydney International Boat Show - all systems go!   
UK superyacht industry on the rise   
EOMAP modelling shows what's under our water   
Great Barrier Reef in a bad state, and getting worse   
Gold Coast International Marine Expo - Organisers add extra sites   
Series Point’s Championship - Formula Two team secures a second place   
Marine Rescue volunteers called to rescue second vessel out of fuel   


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/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 PBW
LocalAds   DE  ES  FR  IT