Free Newsletters - Space News - Defense Alert - Environment Report - Energy Monitor
. 24/7 Space News .




ICE WORLD
Arctic Sea Ice Hits Smallest Extent In Satellite Era
by Maria-Jose Vinas for NASA Earth Science News
Greenbelt MD (SPX) Sep 21, 2012


Satellite data reveal how the new record low Arctic sea ice extent, from Sept. 16, 2012, compares to the average minimum extent over the past 30 years (in yellow). Sea ice extent maps are derived from data captured by the Scanning Multichannel Microwave Radiometer aboard NASA's Nimbus-7 satellite and the Special Sensor Microwave Imager on multiple satellites from the Defense Meteorological Satellite Program. Credit: NASA/Goddard Scientific Visualization Studio. For a larger version of this image please go here or lower res version here.

The frozen cap of the Arctic Ocean appears to have reached its annual summertime minimum extent and broken a new record low on Sept. 16, the National Snow and Ice Data Center (NSIDC) has reported. Analysis of satellite data by NASA and the NASA-supported NSIDC at the University of Colorado in Boulder showed that the sea ice extent shrunk to 1.32 million square miles (3.41 million square kilometers).

The new record minimum measures almost 300,000 square miles less than the previous lowest extent in the satellite record, set in mid-September 2007, of 1.61 million square miles (4.17 million square kilometers). For comparison, the state of Texas measures around 268,600 square miles.

NSIDC cautioned that, although Sept. 16 seems to be the annual minimum, there's still time for winds to change and compact the ice floes, potentially reducing the sea ice extent further. NASA and NSIDC will release a complete analysis of the 2012 melt season next month, once all data for September are available.

Arctic sea ice cover naturally grows during the dark Arctic winters and retreats when the sun re-appears in the spring. But the sea ice minimum summertime extent, which is normally reached in September, has been decreasing over the last three decades as Arctic ocean and air temperatures have increased.

This year's minimum extent is approximately half the size of the average extent from 1979 to 2000. This year's minimum extent also marks the first time Arctic sea ice has dipped below 4 million square kilometers.

"Climate models have predicted a retreat of the Arctic sea ice; but the actual retreat has proven to be much more rapid than the predictions," said Claire Parkinson, a climate scientist at NASA Goddard Space Flight Center, Greenbelt, Md. "There continues to be considerable inter-annual variability in the sea ice cover, but the long-term retreat is quite apparent."

The thickness of the ice cover is also in decline.

"The core of the ice cap is the perennial ice, which normally survived the summer because it was so thick", said Joey Comiso, senior scientist with NASA Goddard. "But because it's been thinning year after year, it has now become vulnerable to melt".

The disappearing older ice gets replaced in winter with thinner seasonal ice that usually melts completely in the summer. This year, a powerful cyclone formed off the coast of Alaska and moved on Aug. 5 to the center of the Arctic Ocean, where it churned the weakened ice cover for several days.

The storm cut off a large section of sea ice north of the Chukchi Sea and pushed it south to warmer waters that made it melt entirely. It also broke vast extensions of ice into smaller pieces more likely to melt.

"The storm definitely seems to have played a role in this year's unusually large retreat of the ice", Parkinson said. "But that exact same storm, had it occurred decades ago when the ice was thicker and more extensive, likely wouldn't have had as prominent an impact, because the ice wasn't as vulnerable then as it is now."

NASA scientists derive 2012 sea ice concentration data from microwave instruments aboard Defense Meteorological Satellite Program satellites. The wind data in the visualization is from the National Centers for Environmental Prediction.

.


Related Links
NSIDC's Arctic Sea Ice News and Analysis
NASA Sea Ice Imagery
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
'Planetary emergency' due to Arctic melt, experts warn
New York (AFP) Sept 19, 2012
Experts warned Wednesday of a "planetary emergency" due to the unforeseen global consequences of Arctic ice melt, including methane gas released from permafrost regions currently under ice. Columbia University and the environmental activist group Greenpeace held separate events to discuss US government data showing that the Arctic sea ice has shrunk to its smallest surface area since record- ... read more


ICE WORLD
Protection for Moon, Mars astronauts eyed

Russia to start research base on the Moon

Remains of astronaut legend Neil Armstrong buried at sea

Memorial service honors 'man on the moon' Armstrong

ICE WORLD
NASA Mars Rover Targets Unusual Rock En Route to First Destination

Dark Bands Run Through Light Layers

NASA Mars Rover Curiosity Looks at Ground Ahead, Moons Above

'Jake Matijevic' Contact Target for Curiosity

ICE WORLD
Cavenauts return to Earth

Brazil unveils tax incentives to boost tech innovation

New Technology Being Stymied by Copyright Law

Boeing Establishes Configuration of Commercial Crew Transportation

ICE WORLD
Tiangong Orbit Change Signals Likely Date for Shenzhou 10

China Focus: Timeline for China's space research revealed

China eyes next lunar landing as US scales back

China unveils ambitious space projects

ICE WORLD
Crew Members Prepare for Departure

ISS Crew Lands Safely in Kazakhstan

ISS Crew Enjoys Light Duty Day

Europe's ATV-3 Spacecraft to Readjust Space Station's Orbit

ICE WORLD
Fueling underway with the Galileo satellites for next Soyuz launch from French Guiana

SpaceX, NASA Target Oct. 7 Launch For Resupply Mission To Space Station

Failure Review Oversight Board Establishes Proton Return to Flight Schedule

HISPASAT chooses Arianespace to launch its Amazonas 4A and AG1 satellites

ICE WORLD
Meteors Might Add Methane to Exoplanet Atmospheres

Two 'hot Jupiters' found in star cluster: NASA

Planets Can Form in the Galactic Center

Birth of a planet

ICE WORLD
iPhone 5 rollout draws big crowds worldwide

Using a laser to 'see' the smallest world

YouTube seeking education video 'gurus'

Angling for gold




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