 |
|
NASA data show Arctic saw fastest August sea ice retreat on record
September 29, 2008Following a record-breaking season of arctic sea ice decline in 2007, NASA scientists have kept a close watch on the 2008 melt season. Although the melt season did not break the record for ice loss, NASA data are showing that for a four-week period in August 2008, sea ice melted faster during that period than ever before.
Each year at the end of summer, sea ice in the Arctic melts to reach its annual minimum. Ice that remains, or "perennial ice," has survived from year to year and contains old, thick ice. The area of arctic sea ice, including perennial and seasonal ice, has taken a hit in past years as melt has accelerated. Researchers believe that if the rate of decline continues, all arctic sea ice could be gone within the century.
"I was not expecting that ice cover at the end of summer this year would be as bad as 2007 because winter ice cover was almost normal," said Joey Comiso of NASA's Goddard Space Flight Center in Greenbelt, Md. "We saw a lot of cooling in the Arctic that we believe was associated with La Niña. Sea ice in Canada had recovered and even expanded in the Bering Sea and Baffin Bay. Overall, sea ice recovered to almost average levels. That was a good sign that this year might not be as bad as last year."
The 2008 sea ice minimum was second to 2007 for the record-lowest extent of sea ice, according to a joint announcement Sept. 16 by NASA and the University of Colorado's National Snow and Ice Data Center (NSIDC) in Boulder, Colo. As of Sept. 12, 2008, the ice extent was 1.74 million square miles. That's 0.86 million square miles below the average minimum extent recorded from 1979 to 2000, according to NSIDC.
Contributing to the near-record sea ice minimum in 2008 was a month-long period in the summer that saw the fastest-ever rate of seasonal retreat during that period. From August 1 to August 31, NASA data show that arctic sea ice extent declined at a rate of 32,700 square miles per day, compared to a rate of about 24,400 square miles per day in August 2007. Since measurements began, the arctic sea ice extent has declined at an average rate of 19,700 miles per day at the point when the extent reaches its annual minimum.
Observations of changes to sea ice over time are possible due to a 30-year record of data from NASA and other agency satellites, including Nimbus-7, Aqua, Terra and the Ice, Cloud, and land Elevation Satellite (ICESat).
Researchers say that the recent seasonal acceleration could be in part due to conditioning going on in the Arctic. For example, research by Jennifer Kay of the National Center for Atmospheric Research in Boulder, Colo., and colleagues reported this April in Geophysical Research Letters that reduced cloud cover in 2007 allowed more sunlight to reach Earth, contributing to a measureable amount of sea ice melt at the surface. Reduced cloud cover also contributed to warmer ocean surface temperatures that led to melting of the ice from below.
"Based on what we've learned over the last 30 years, we know that the perennial ice cover is now in trouble," Comiso said. "You need more than just one winter of cooling for the ice to recover to the average extent observed since the measurements began. But the trend is going the other way. A warming Arctic causes the surface water to get warmer, which delays the onset of freeze up in the winter and leads to a shorter period of ice growth. Without the chance to thicken, sea ice becomes thinner and more vulnerable to continued melt."
NASA/Goddard Space Flight Center
The 2008 sea ice minimum was second to 2007 for the record-lowest extent of sea ice, according to a joint announcement Sept. 16 by NASA and the University of Colorado's National Snow and Ice Data Center (NSIDC) in Boulder, Colo. As of Sept. 12, 2008, the ice extent was 1.74 million square miles. That's 0.86 million square miles below the average minimum extent recorded from 1979 to 2000, according to NSIDC.
Contributing to the near-record sea ice minimum in 2008 was a month-long period in the summer that saw the fastest-ever rate of seasonal retreat during that period. From August 1 to August 31, NASA data show that arctic sea ice extent declined at a rate of 32,700 square miles per day, compared to a rate of about 24,400 square miles per day in August 2007. Since measurements began, the arctic sea ice extent has declined at an average rate of 19,700 miles per day at the point when the extent reaches its annual minimum.
Observations of changes to sea ice over time are possible due to a 30-year record of data from NASA and other agency satellites, including Nimbus-7, Aqua, Terra and the Ice, Cloud, and land Elevation Satellite (ICESat).
Researchers say that the recent seasonal acceleration could be in part due to conditioning going on in the Arctic. For example, research by Jennifer Kay of the National Center for Atmospheric Research in Boulder, Colo., and colleagues reported this April in Geophysical Research Letters that reduced cloud cover in 2007 allowed more sunlight to reach Earth, contributing to a measureable amount of sea ice melt at the surface. Reduced cloud cover also contributed to warmer ocean surface temperatures that led to melting of the ice from below.
"Based on what we've learned over the last 30 years, we know that the perennial ice cover is now in trouble," Comiso said. "You need more than just one winter of cooling for the ice to recover to the average extent observed since the measurements began. But the trend is going the other way. A warming Arctic causes the surface water to get warmer, which delays the onset of freeze up in the winter and leads to a shorter period of ice growth. Without the chance to thicken, sea ice becomes thinner and more vulnerable to continued melt."
NASA/Goddard Space Flight Center
Sea Ice Current Events and Sea Ice News RSSCave Study Links Climate Change to California Droughts
California experienced centuries-long droughts in the past 20,000 years that coincided with the thawing of ice caps in the Arctic.
Last time carbon dioxide levels were this high: 15 million years ago, scientists report
You would have to go back at least 15 million years to find carbon dioxide levels on Earth as high as they are today, a UCLA scientist and colleagues report Oct. 8 in the online edition of the journal Science.
NASA flies to Antarctica for largest airborne polar ice survey
NASA begins a series of flights Oct. 15 to study changes to Antarctica's sea ice, glaciers and ice sheets. The flights are part of Operation Ice Bridge, a six-year campaign that is the largest airborne survey ever made of ice at Earth's polar regions.
Peering under the ice of a collapsing polar coast
Starting this month, a giant NASA DC-8 aircraft loaded with geophysical instruments and scientists will buzz at low level over the coasts of West Antarctica, where ice sheets are collapsing at a pace far beyond what scientists expected a few years ago.
Arctic sea ice recovers slightly in 2009, remains on downward trend, says U. of Colorado report
Despite a slight recovery in summer Arctic sea ice in 2009 from record-setting low years in 2007 and 2008, the sea ice extent remains significantly below previous years and remains on a trend leading toward ice-free Arctic summers, according to the University of Colorado at Boulder's National Snow and Ice Data Center.
Arctic Sea ice extent is third lowest on record
U.S. satellite measurements show Arctic sea ice extent in 2009 - the area of the Arctic Ocean covered by floating ice - was the third lowest since satellite measurements were first made in 1979.
Algae and pollen grains provide evidence of remarkably warm period in Antarctica's history
For Sophie Warny, LSU assistant professor of geology and geophysics and curator at the LSU Museum of Natural Science, years of patience in analyzing Antarctic samples with low fossil recovery finally led to a scientific breakthrough.
Arctic sea ice reaches minimum extent for 2009, third lowest ever recorded
The Arctic sea ice cover appears to have reached its minimum extent for the year, the third-lowest recorded since satellites began measuring sea ice extent in 1979, according to the University of Colorado at Boulder's National Snow and Ice Data Center.
UA scientists seek new emphases in Arctic climate change research
Much of circumpolar Arctic research focuses on the physical, direct changes resulting from climate warming such as sea ice retreat and temperature increases.
Satellites and submarines give the skinny on sea ice thickness
This summer, a group of scientists and students - as well as a Canadian senator, a writer, and a filmmaker - set out from Resolute Bay, Canada, on the icebreaker Louis S. St-Laurent.
More Sea Ice Current Events and Sea Ice News Articles
 |
Sea Ice: An Intorduction to its Physics, Chemistry, Biology and Geology by David N. Thomas (Editor), G. S. Dieckmann (Editor) Sea ice, which covers up to 7% of the planet’s surface, is a major component of the world’s oceans, partly driving ocean circulation and global climate patterns. It provides a habitat for a rich diversity of marine organisms, and is an extremely valuable source of information in studies of global climate change and the evolution of present day life forms. Increasingly sea ice is being used as a proxy for extraterrestrial ice covered systems. Sea Ice provides a comprehensive review of our current available knowledge of polar pack ice, the study of which is severely constrained by the logistic difficulties of working in such harsh and remote regions of the earth. The book’s editors, Drs Thomas and Dieckmann have drawn together an impressive group of international... |
 |
Sea Ice by David N. Thomas (Editor), Gerhard S. Dieckmann (Editor) As the Arctic perennial sea ice continues to disappear at an alarming rate, a full understanding of sea ice as a crucial global ecosystem, and the effects of its loss is vital for all those working with and studying global climate change. Building on the success of the previous edition, the second edition of Sea Ice, now much expanded and in full colour throughout, includes six completely new chapters with complete revisions of all the chapters included from the first edition. The Editors, Professor David Thomas and Dr Gerhard Dieckmann have once again drawn together an extremely impressive group of internationally respected contributing authors, ensuring a comprehensive worldwide coverage of this incredibly important topic. Sea Ice, second edition, is an... |
 |
3 Silicone Ice Tray Sea Shaped Cube Mold Party Fun New by 4 Seasons 3 Brand New Silicone Ice Cube Trays. These durable trays have sea life shapes that give your ice you a fun look! Flexible and easy to use. Freezer and refrigerator safe. Easy to wash. Each tray makes: 2 crabs 2 nutmeg shells 2 sea stars 2 scallop shells Perfect for parties and for kids! Available colors: Green, Orange & Blue. Measures: 4.25" W 8.75" L x 1" H Cube size:1.5" x 1.5" x 1" (approx.) Sealed in original package. |
![Nature: Under Antarctic Ice/Encountering Sea Monsters [Blu-ray]](http://ecx.images-amazon.com/images/I/51VXooyLRmL._SL160_.jpg) |
Nature: Under Antarctic Ice/Encountering Sea Monsters [Blu-ray] Starring: Hilary Swank, Tim Matheson Directed By: NATURE produced by WNET Program 1: Under Antarctic Ice - Beneath the surface of stunningly cold water, an abundance of lifeforms and icescapes can be found. Academy Award-winner Hilary Swank narrates encounters with jellyfish that have thirty-foot long tentacles, sponges the size of large mammals, killer whales, and more in this fascinating look at what lies in the ocean depths beneath the surface of one of the coldest continents on Earth. Program 2: Encountering Sea Monsters - Enter the gloomy green ocean depths with deep-sea cameraman Bob Cranston to discover fantastic worlds and the beautiful but deadly creatures that inhabit them. Nothing in science fiction can prepare you for a creature with a beak like a parrot, no bones in its body, three hearts, blue blood, skin that can change colors, and arms... |
 |
Diesel Men's Ice Cool Lace-up Sneaker,White/Turkish Sea,13 M US by Diesel |
 |
Piggy Polish Toe Nail Polish, Polar Sea Ice by Piggy Polish A fun, colorful way to show off your toes! Professional quality, long lasting toe nail polish. |
 |
Ship of Ice Directed By: Peter Lynch Also With: John Davis (Producer), Eco-Nova Productions Ltd. (Producer), Thor Henrikson (Writer) |
|
Hotpuppy So Many Fish in the Sea Tee in Ice Grey in XX-Large by Hotpuppy | |
 |
Fire N and Ice Dragons Mega Bloks Fyren Sea Phoenix Warship by Mega Bloks Part of the Fire Ice Dragons Mega Bloks collection, the Fyren Sea Phoenix is a 210-piece building set that will launch your imagination into the land of dragons! |
 |
SEA ICE 1/4 OZ ANTI FOG by MCNETT THUNDER SHIELD SPRAY Specialized liquid formula provides gentle cleaning. Easy in-field application. Safe for all glass and plastic lenses. Limited quantity on Sea Ice Anti Fog. |
| © 2009 BrightSurf.com |