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What is the Arctic Ice ‘Death Spiral’?

August 14, 2013 1 comment

tcktcktck.org

Sea Ice Spiral

Arctic sea ice in the summer. Creative Commons: Guido Appenzeller, 2011

“The record or near-records being reported from year to year in the Arctic are no longer anomalies or exceptions. Really they have become the rule for us, or the norm that we see in the Arctic and that we expect to see for the forseeable future” – Jackie Richter-Menge, US Army Corps of Engineers

Last week’s ‘State of the Climate’ report confirmed it: ice is melting in the Arctic at one of the fastest rates in human history. Researchers and climate scientists monitoring ice melt in the Arctic have started using the ominous term ‘death spiral’ to describe what’s happening at the top of the world. But what does it mean? And is Read more…

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NOAA: 2012 shows climate change with record sea-level rise, Arctic melting, heated-up oceans

August 7, 2013 Comments off
washingtonpost.com

2012 arctic ice meltWASHINGTON — A new massive federal study says the world in 2012 sweltered with continued signs of climate change. Rising sea levels, snow melt, heat buildup in the oceans, and melting Arctic sea ice and Greenland ice sheets, all broke or nearly broke records, but temperatures only sneaked into the top 10.

The National Oceanic and Atmospheric Administration on Tuesday issued a peer-reviewed 260-page report, which agency chief Kathryn Sullivan calls its annual “checking on the pulse of the planet.” The report, written by 384 scientists around the world, compiles data already released, but it puts them in context of what’s been happening to Earth over decades.

“It’s critically important to compile a big picture,” National Climatic Data Center director Tom Karl says. “The signs that we see are of a warming world.”

Sullivan says what is noticeable “are remarkable changes in key climate indicators,” mentioning dramatic spikes in ocean heat content, a record melt of Arctic sea ice in the summer, and Read more…

Arctic Soil Releases Dangerous Levels of CO2, Speeding Global Warming

February 12, 2013 Comments off

scienceworldreport.com

Arctic

(Photo : Reuters) Global warming has caused scientists to worry as permafrost melts, releasing a vast amount of CO2 into the atmosphere and further perpetuating the problem.

For most of the year, the Arctic is frozen: its hard-packed tundra and ice forming solid ground. In fact, some of that ice never melts in what is known as permafrost, which stays solid all year. Now, global warming has caused scientists to worry as permafrost melts, releasing a vast amount of CO2 into the atmosphere and further perpetuating the problem.

Flooding triggered by melting snow washes vast amounts of carbon-rich soil from the land into the water. These waters contain most of the carbon that is currently being released from melting permafrost. Permafrost itself contains years of collected organic matter and when it collapses, it exposes new layers of soil to sunlight. Once this carbon is exposed, it is then oxidized by bacteria and produces CO2. In fact, scientists estimate that carbon from Read more…

Arctic Sea Ice Melt May Trigger Extreme European Winter

September 18, 2012 Comments off

wired.com

Image: Jenny Downing/Flickr

By Stephen Leahy, the Guardian

The record loss of Arctic sea ice this summer may mean a cold winter for the UK and northern Europe. The region has been prone to bad winters after summers with very low sea ice, such as 2011 and 2007, said Jennifer Francis, a researcher at Rutgers University.

“We can’t make predictions yet … [but] I wouldn’t be surprised to see wild extremes this winter,” Francis told the Guardian.

This year’s ice melt has broken the 2007 record by an an area larger than the state of Texas.

Polar ice experts “thought that it would be many years until we again saw anything like we saw in 2007″, said Mark Serreze, director of the National Snow and Ice Data Centre in Colorado.

The unprecedented expanse of ice-free Arctic Ocean has been absorbing the Read more…

Arctic sea ice extent continues to melt below former record lows: data center

September 6, 2012 Comments off

nunatsiaqonline

Every year there's less of the multi-year, blue-tinged sea ice, like this ice seen in the Northwest Passage, in the Arctic. (PHOTO BY JANE GEORGE)
Every year there’s less of the multi-year, blue-tinged sea ice, like this ice seen in the Northwest Passage, in the Arctic. (PHOTO BY JANE GEORGE)
Arctic sea ice extent for August 2012 was 4.72 million sq. km.The magenta line shows the 1979 to 2000 median extent for that month. The black cross indicates the geographic North Pole. (IMAGE COURTESY OF THE NSIDC)

Following the new record low Arctic sea ice extent recorded Aug. 26, ice coverage has continued to drop and has now shrunk to less than four million square kilometres — smaller than the previous low extent of 2007.

Compared to September conditions in the 1980s and 1990s, the Arctic sea ice extent has dropped by 45 per cent, the Colorado-based National Snow and Ice Data Center said Sept. 5.

And that skimpy sea ice cover is likely to get lower yet, because Read more…

Oldest and thickest Arctic sea ice is disappearing

March 1, 2012 1 comment

earth-issues.com

Oldest Arctic Sea Ice is Disappearing

acquired November 1, 2011 – January 31, 2012download large image (1 MB, JPEG, 3840×2160)

A new study by NASA scientist Joey Comiso has found that the oldest and thickest Arctic sea ice is disappearing at a faster rate than the younger and thinner ice at the edges of the ice cap. The rapid disappearance of older ice makes the Arctic Ocean’s sea ice cap more vulnerable to further decline.

Arctic multi-year ice “extent”—which includes all areas where at least 15 percent of the ocean surface is covered by multi-year ice—has been vanishing at a rate of –15.1 percent per decade, Comiso found. Over the same period, the “area” covered by multi-year ice—which discards open water among ice floes and focuses exclusively on regions that are completely covered—has been shrinking by –17.2 percent per decade. The findings were Read more…

Low temperatures enhance ozone degradation above the Arctic

January 19, 2012 Comments off

physorg.com

March 2011: This shows strongly reduced ozone values (left, dark blue) and significantly increased concentration of chlorine monoxide (right, red) that is directly involved in ozone degradation. Credit: Figure: IMK-ASF, KIT

About a year ago, IMK scientists, together with colleagues from Oxford, detected that ozone degradation above the Arctic for the first time reached an extent comparable to that of the ozone hole above the . Then, the KIT researchers studied the mechanisms behind. Their results have now been published in the journal .

According to IMK studies, occurrence of the Arctic ozone hole was mainly due to the extraordinarily in the ozone layer that is located at about 18 km height in the stratosphere, i.e. the second layer of the earth’s atmosphere. There, originating from chlorofluorocarbons (CFC, e.g. and refrigerants) and other pollutants are converted chemically at temperatures below -78°C. These chemical conversion products attack the ozone layer and destroy it partly. One of the main statements in the study: If the trend to colder temperatures in the stratosphere observed in the past decades will continue, repeated occurrence of an Arctic ozone hole has to be expected.

The team of IMK researchers analyzed measurements of the chemical composition of the atmosphere by the MIPAS satellite instrument developed by KIT. In addition, model calculations were made to Read more…

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