RELATED e360 DIGEST ITEMS

10 Nov 2009: Retreating Antarctic Ice Has
Created New Carbon Sink, Study Says

The melting of Antarctic ice has allowed large blooms of tiny marine phytoplankton to flourish, creating a significant new biological sink for carbon, according to a new study by the British Antarctic Survey. Over the last five decades, retreating glaciers around the Antarctic Peninsula have opened about 24,000 square kilometers of open water that has been colonized by the carbon-absorbing phytoplankton, according to the study being published in the journal Global Change Biology. After the phytoplankton dies, it eventually sinks to the ocean floor where it can store carbon for thousands or millions of years. The researchers estimate this new carbon sink will absorb about 3.5 million tons of carbon from the ocean and atmosphere annually. “Although this is a small amount of carbon compared to global emissions of greenhouse gases in the atmosphere, it is nevertheless an important discovery,” said the study's lead author, Lloyd Peck. The authors called the new bloom the second largest factor acting against climate change so far discovered on Earth (the largest being new forest growth in the Arctic).
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30 Oct 2009: Thick, Multi-Year Arctic Ice
Has Effectively Disappeared, Scientist Says

One of Canada’s top Arctic experts, recently returned from an expedition in the far north, has told the Canadian parliament that the Arctic’s thick, multi-year sea ice has largely vanished, removing the last barrier to ships navigating the polar region. David Barber, Canada’s Research Chair in Arctic System Science at the University of Manitoba, said his expedition aboard an icebreaker was looking for a huge pack of thick ice that has existed for tens of thousands of years in the Beaufort Sea. But that multi-year ice, often dozens of feet thick, has largely been replaced by one-year-old “rotten” ice less than 20 inches thick, which is not an impediment to navigation. “We are almost out of multi-year ice in the northern hemisphere,” Barber told Parliament. “I’ve never seen anything like this in my 30 years of working in the high Arctic... From a practical perspective, we almost have a seasonally ice-free Arctic now.” Barber’s icebreaker did find a 10-mile-wide floe of multi-year ice that was 20 to 26 feet thick, but he said the expedition watched as those floes began breaking apart after being hit large waves. In 2007, the extent of Arctic sea ice, most of it thin, was 40 percent below the long-term average.
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23 Oct 2009: Protected Polar Bear Habitat
Proposed by U.S. Government in Alaska

The U.S. Interior Department is proposing that more than 200,000 square miles of land, sea, and ice in Alaska and nearby waters be given special protection to help preserve 3,500 polar bears threatened by the rapid loss of Arctic sea ice. The Interior Department has proposed designating the vast area as “critical habitat,” which means that any government agency or company must show that activities such as oil drilling and shipping will not affect the bears’ habitat or accelerate the extinction of the species. In 2008, the Interior Department declared that polar bears were threatened with extinction. Shell Oil this week was given permission to drill in the proposed protected area, and conservation groups have criticized the Interior Department for not banning all oil and gas activity in the protected zone. Meanwhile, the National Oceanic and Atmospheric Administration has released its annual “Arctic Report Card” saying there is mounting evidence of widespread warming in the Arctic, including a drastic reduction in thick, multi-year sea ice; record-setting heat in Greenland and other parts of the Arctic; an unprecedented amount of freshwater on the surface of the Atlantic from melting ice; and growing evidence that Arctic warming is altering weather patterns in the northern hemisphere.
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15 Oct 2009: Major Arctic Ice Survey
Finds Significant Drop in Ice Thickness

A pioneering expedition to the North Pole, during which a team trekking across the Arctic Ocean drilled 1,500 holes in the ice, has found that most of the ocean is covered by thinner, first-year ice, leading scientists to forecast that the ocean will be largely ice-free in summer within a decade or two. The Catlin Arctic Survey, carried out last spring as the expedition trekked for 73 days across 280 miles of the northern Beaufort Sea to the North Pole, determined that the average thickness of ice in the area was close to six feet. Analyzing the data, ice experts said that much of the sea ice is only about a year old, replacing the thicker ice, formed over many decades, that once covered the sea. Measurements made by nuclear submarines in the 1950s showed that much of the northern Beaufort Sea was once covered by multi-year ice that was twice as thick. “With a larger part of the region now first-year ice, it is clearly more vulnerable,” said Peter Wadhams of the Polar Ocean Physics Group at Cambridge University. “The area is more likely to become open water each summer.” Within 10 to 20 years, Wadhams said, the Arctic Ocean “will essentially be an open sea in the summer.”
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12 Oct 2009: U.S. Scientists Back Reduction
In Drilling Plans Off Coasts and in Arctic

Scientists at the National Oceanic and Atmospheric Administration (NOAA) have recommended dramatically scaling back oil drilling plans off U.S. coasts and have proposed a ban on oil and gas exploration in the Arctic until oil companies significantly improve their ability to prevent and clean up oil spills. The non-binding recommendations to U.S. Interior Secretary Ken Salazar represent a stark reversal from the pro-drilling policies of the Bush administration; the new administrator of NOAA, Jane Lubchenco, is an oceanographer who has vowed to restore science to federal environmental policy. The NOAA scientists recommended excluding large tracts of coastline off California, the Atlantic seaboard, the Gulf of Mexico, and Alaska from a proposed 2010 to 2015 drilling plan that had been pushed by the Bush administration. The scientists said the previous plan understated the risks that oil exploitation posed to marine life and coastlines. In recommending the temporary Arctic drilling ban, the scientists expressed concern about the impact of potential oil spills on commercial and subsistence fisheries in the North Aleutian Basin and Chukchi Sea.
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07 Oct 2009: From ‘Albatross Cam’
New Insights into Foraging Behavior

By attaching small digital cameras to the backs of several albatrosses in the sub-Antarctic, Japanese and British scientists have discovered that the great seabirds sometimes feed in conjunction with pods of killer whales, apparently picking up scraps left by the predatory mammals. The researchers affixed the cameras to four black-browed albatrosses captured on Bird Island in South Georgia in January, then retrieved three of the four cameras when the seabirds returned to their breeding colonies. The scientists collected nearly 29,000 digital images, some of which showed albatrosses flying behind killer whales and landing in the sea near the orcas. Reporting in the journal PLoS ONE, the scientists said that the albatrosses appeared to be feeding on scraps of Patagonian toothfish or other prey devoured by the killer whales. Such interactions between albatrosses and killer whales have rarely been observed, and the researchers said that one way albatrosses may locate prey in a vast, featureless sea is by spotting orcas and feeding in their vicinity. The cameras, each weighing 82 grams, captured other images of fellow albatrosses in flight, as well as icebergs adrift in the Southern Ocean.
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06 Oct 2009: Arctic Sea Ice Extent
At Third-Lowest Level Since 1979

The extent of ice covering the Arctic Ocean reached its third-lowest level this summer since satellite observations began in 1979, rebounding from record lows in 2007 and 2008, according to the U.S. National Snow and Ice Data Center (NSIDC). Arctic sea ice, measured at its low point in September, covered an area of two million square miles last month — 649,000 square miles below the September average from 1979 to 2000. This year’s summer sea ice extent was nevertheless 409,000 square miles greater than the record low ice extent set in 2007. Ice extent grew this year, scientists say, because cloudy skies in late summer kept sea surface temperatures lower and because atmospheric patterns in August and September helped to spread out the ice pack. Despite the rebound in extent, ice thickness continues to decline, with only 19 percent of the ice cover more than two years old — far below the 1981 to 2000 average of 52 percent. Arctic sea ice is still declining at a rate of 11 percent per decade. “It’s nice to see a little recovery over the past couple years, but there’s no reason to think that we’re headed back to conditions seen back in the 1970s,” said NSIDC director and senior scientist Mark Serreze. “We still expect to see ice-free summers sometime in the next few decades.”
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24 Sep 2009: Melting of Greenland and Antarctica Ice Sheets is Accelerating

Ice sheets on the edges of Greenland and western Antarctica are melting faster than expected, new satellite information shows, and scientists say in some regions the melt is accelerating at “runaway” speeds. Ice in some parts of Antarctica has lost about 30 feet of thickness each year since 2003, according to a report published in the journal Nature. The rate of melt during that span is about 50 percent faster than it was from 1995 to 2003. The findings, which are based on laser readings from a NASA satellite, confirm concerns among some climate scientists that the accelerating rate of ice sheet melting has become a self-feeding phenomenon — essentially, the more the ice melts, the more the water near the ice sheets causes more melting. “The question is how far will it run?” said Hamish Pritchard of the British Antarctic Survey and lead author of the study. “It’s more widespread than we previously thought.” According to researchers, 81 of the 111 Greenland glaciers are melting at an accelerated pace. The study does not indicate how this acceleration will affect sea level rise.
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11 Sep 2009: With Melting Arctic Ice, Ships Prepare to Complete Northern Passage

Aided by thawing sea ice, two German ships are en route to becoming the first commercial vessels to complete the Northern Sea Route through the Arctic from Asia to the West. The ships, which began their voyage in South Korea in July, are scheduled to depart a Siberian port this week for Rotterdam in the Netherlands. “It is global warming that enables us to think about using that route,” a spokeswoman for the shipping company, the Beluga Group, told the New York Times. The ships have been accompanied by Russian icebreakers, but reportedly so far have encountered only scattered ice floes. The Russian government declared the Northern Sea Route, or Northeast Passage, open for international vessels after the collapse of the Soviet Union, but no commercial ships have yet traveled all the way across. The Russians hope that the melting sea ice, combined with economic benefits, will eventually make the Arctic passage a strong competitor to longer southerly routes.
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04 Sep 2009: Millennia of Arctic Cooling
Came to Abrupt End in 20th Century

Greenhouse gases released by human activity have swiftly ended a millennia-long trend of cooling in the Arctic and may well halt the next cyclical descent into an ice age, according to a new study. The report — based on a study of glacial ice, lakebed mud, and tree rings that provide a decade-by-decade record of Arctic climate for the past 2,000 years — demonstrates that humankind is now pouring so many greenhouse gases into the atmosphere that we are interfering with ancient cycles of ice ages and inter-glacial periods that have occurred for millions of years. Writing in the journal Science, researchers reported that until 1900, the Arctic was cooling at a rate of half a degree Fahrenheit per millennium for the past 2,000 years. This was because of a natural cycle in which earth’s orbit is farther from the sun. But since 1900, the Arctic has warmed 2.2 degrees F, with 1998 to 2008 being the warmest decade in 2,000 years. This precipitous warming caused by heat-trapping greenhouses gases is not only melting Arctic Ocean ice and the Greenland ice sheet but, if not brought under control, may stave off the arrival of the next Ice Age, expected in roughly 20,000 years.
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02 Sep 2009: Summer Sea Ice in Arctic
Could Disappear by 2016, Scientists Say

Summer sea ice covering the Arctic Ocean could disappear by 2016 and the thawing of the Greenland ice sheet is occurring so rapidly that the meltwater from Greenland alone could raise sea levels by one meter this century. Meeting in Greenland, scientists from the Danish Meteorological Institute, the Greenland Climate Center, and other organizations said that the thickness and volume of Arctic ice is decreasing at an even more rapid rate than the precipitous decline in ice extent; Arctic Ocean winter ice thinned by 2.2 feet from 2004 to 2008. As a result, the Danish researchers said it is quite likely that much of the Arctic ocean could be ice-free in summer by 2016. In addition, the scientists said that the Greenland ice sheet has been losing mass at a rate of 240 cubic kilometers (58 cubic miles) of ice per year in the last five years, with the loss accelerating in the past two years. Up until now, the loss of mass of the Greenland ice sheet has been concentrated in the southern part of the country, but the melting and ice loss is spreading north, the scientists reported.
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21 Aug 2009: Expansion of Arctic Fishery
Prohibited Until Further Study by U.S.

With Arctic summer sea ice rapidly disappearing, U.S. Secretary of Commerce Gary Locke has prohibited the expansion of fishing into ice-free seas until scientists can study the marine life in the newly opened waters and devise a sustainable fishing plan. The new federal fisheries plan, hailed by environmental groups and commercial fishing interests, would prohibit commercial fishing in nearly 200,000 square miles of federal waters in the Beaufort and Chukchi seas. Scientists are beginning to study the areas within 200 miles of the Alaska coast to determine the type and abundance of fish species, after which they are to propose a plan for limited commercial fishing. Among the commercial species likely to be targeted are Arctic cod, saffron cod, and snow crab. Locke’s decision will not affect fishing for Pacific salmon, halibut, whitefish, and shellfish close to the Alaskan coast. Commercial fishing interests said the plan will prevent the over-exploitation of fisheries stocks in the newly opened waters, and environmental groups said the plan represented the first instance in which management guidelines will be developed before an area is opened to fishing.
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17 Aug 2009: Large Plumes of Methane
Discovered Off Spitsbergen in Arctic

British and German scientists have discovered 250 plumes of methane gas rising from the thawing seabed off the Spitsbergen archipelago in the Norwegian Arctic, apparently a result of the warming of the West Spitsbergen current. The researchers measured the plumes rising from the seabed at a depth of 150 to 400 meters (500 to 1,300 feet). The methane — a potent greenhouse gas — is being released by frozen methane hydrates on the sea floor, which are thawing as a result of a 1 degree C (1.8 F) warming of the West Spitsbergen current in the last 30 years, the scientists said. Most of the methane is absorbed by the ocean before it reaches the surface, but the gas increases the acidity of the ocean, which inhibits the ability of marine creatures to grow shells. Scientists fear that as the world’s oceans warm, huge amounts of methane will be released. The Spitsbergen researchers said they were surprised by the large number of methane plumes. “Our survey was designed to work out how much methane might be released by future ocean warming,” said one scientist. “We did not expect to discover such strong evidence that this process has already started.”
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31 Jul 2009: Arctic Tundra Undergoing
Major Changes As it Warms, Studies Show

Several recent studies show that the rapid warming of Arctic tundra is leading to a host of sweeping changes, including more extensive fires, the growth of larger vegetation, more absorption of solar energy, melting permafrost, and substantially larger releases of carbon dioxide, methane, and other greenhouse gases. Taken together, the studies demonstrate that rising temperatures set in motion a vicious circle of more warming and higher releases of greenhouse gases. In Alaska, scientists studying a 2007 fire that burned nearly 400 square miles of the Brooks Range found that the burned tundra lost 40 to 120 grams of carbon per square meter, while pristine tundra absorbed 30 to 70 grams. Burned tundra also absorbed 71 percent more solar radiation than normal and caused permafrost to melt to a depth of several inches. A study in the Canadian Arctic has shown that tundra vegetation is becoming weedier, larger, and darker, significantly increasing the amount of absorbed sunlight and further boosting temperatures. The study also showed the warming tundra giving off unexpectedly high levels of methane and nitrous oxide. And in Scandinavia researchers found that by warming Arctic peatlands by nearly 2 degrees F over eight years, the tundra released an extra 60 percent CO2 in spring and 52 percent in summer, according to a study in the journal, Nature.
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17 Jul 2009: U.S. Agency Releases
Spy Satellite Images of Arctic Ice

The U.S. government has released 1,200 photographs of Arctic sea ice taken by spy satellites, a trove of images that scientists say will better help them understand the dynamics of the melting northern ice cap. The U.S. Geological Survey released the images just hours after the National Academy of Sciences had called for their dissemination. Seven hundred of the photographs depict sea ice at six Arctic sites outside of the U.S., while 500 images show 22 sites in Alaskan waters. Scientists said that the extremely fine resolution of the spy satellite images — one yard — will enable them to better understand processes such as the formation of melted pools of water on the surface of sea ice, which hastens the disintegration of the ice. Scientists said that by studying the photographs — which span the last nine years, at least — they will be able to develop more accurate models of what might happen to Arctic sea ice as warming continues. “These... one-meter images... give you a big picture of the summertime Arctic,” said Thorsten Markus of NASA’s Goddard Space Flight Center, which studies climate change. “This is the main reason we are so thrilled about it.”
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02 Jun 2009: Emperor Penguin Colonies
Discovered by Spotting Guano from Space

Poring over satellite photographs, researchers from the British Antarctic Survey (BAS) have discovered 10 new emperor penguin colonies in Antarctica by spotting telltale brown excrement patches on snow and ice. Emperor penguins — the world’s largest penguin, reaching four feet tall and weighing more than 80 pounds — spend eight months breeding and rearing chicks on sea ice around Antarctica, creating large fields of guano. Studying satellite photographs taken from 1999 to 2004, BAS researchers discovered 10 previously unknown emperor penguin colonies and learned that four previously known colonies had disappeared. Based on this research, published in the journal Global Ecology and Biogeography, the researchers concluded that 38 emperor penguin colonies now exist in Antarctica, harboring a population of 200,000 to 400,000 breeding pairs. The life cycle of emperor penguins is heavily dependent on sea ice, and numerous researchers have predicted recently that as Antarctica warms and sea ice melts, emperor populations will decline sharply.
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15 May 2009: Study Halves Projected
Sea Rise if Antarctic Ice Sheets Melt

The disintegration of Antarctica’s vast western ice sheets would cause seas to rise only half as much as previously estimated, according to a new report. While previous studies projected that a partial or total collapse of Antarctica's massive western sheets would raise seas by about 20 feet, a new report published in the journal Science suggests that sea levels would rise by only about 11 feet. The study combined computer modeling with measurements of the ice and the underlying bedrock. “Our calculations show those [earlier] estimates are much too large, even on a thousand-year timescale,” said the study's lead author, Jonathan Bamber, of the University of Bristol. Scientists consider West Antarctica vulnerable to collapse because so much of the ice sits on bedrock well below sea level. But while the new report is less dire than earlier projections, the authors called for renewed investment in satellite monitoring to clarify the global risk. They predict seas will rise 25 percent more on both U.S. coasts because shifting such a mass of ice would alter gravity locally and cause water to build up in the northern oceans.
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28 Apr 2009: Wilkins Breakup Continues

The recent collapse of a vital buttress in Antarctica’s Wilkins Ice Shelf is now leading to the fracturing of large icebergs from the massive floating ice sheet, according to recent satellite photos from the European Space Agency. The pictures show that since the disintegration of a 25-mile-long ice bridge on April 2, icebergs equaling the size of New York City have split off from the ice shelf and floated into a nearby bay. The image, captured by the space agency’s Envisat satellite, shows the area — outlined in pink — where icebergs have calved from the northern end of the Wilkins Ice Shelf since the disintegration of the ice bridge that had connected the shelf to Charcot Island. The area once occupied by the ice bridge is outlined in white. Rapidly rising temperatures along the Antarctic Peninsula, where the Wilkins Ice Shelf is located, have led to the full or partial breakup of 10 ice shelves in recent decades. The Envisat image shows scores of other icebergs that have broken off recently from the shelf.
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07 Apr 2009: Arctic Ice Volume, Thickness
Now At Record Low Levels, Study Shows

The volume of ice covering the Arctic Ocean is now at record low levels, as thicker, multi-year ice that has blanketed the sea is rapidly melting and being flushed out of the Arctic basin, according to a new study. Analyzing satellite imagery from 1979 to 2008, scientists from NASA and the National Snow and Ice Data Center at the University of Colorado produced dramatic evidence showing that thicker sea ice — which a quarter-century ago covered 30 to 40 percent of the Arctic Ocean — now comprises less than 10 percent of the polar ice cap. As the older ice — which sometimes reaches a thickness of 10 feet or more — disappears, the sea ice covering the Arctic freezes in winter and melts the following summer, leaving record areas of the Arctic Ocean ice-free. The researchers said ice volume in the Arctic was at its lowest level since records began being kept in the 1930s and may be at its lowest point in 8,000 years. The video — based on satellite images since 1979 — shows how older, thicker ice (in red and yellow) is rapidly disappearing from the Arctic.
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24 Mar 2009: Study Shows Southern Ocean May Be Poor Locale For Geo-engineering Plan

A controversial study to see if seeding the Southern Ocean with iron would remove large amounts of carbon dioxide from the atmosphere has shown that the frigid ocean does not appear to be a good locale for the geo-engineering scheme. Indian and German scientists, working aboard the vessel Polar Stern, spent 2 ½ months in the Southern Ocean for an experiment in which they dumped six tons of dissolved iron into a 116-mile patch of ocean. Based on earlier experiments in other oceans, the scientists believed iron fertilization would create large blooms of phytoplankton, or algae, that would absorb CO2 from the air and then sink to the bottom, sequestering the carbon and helping to slow global warming. But the recent experiments showed the fertilization created a type of phytoplankton that was quickly eaten by shrimp-like zooplankton called amphipods, leading to little sequestration. Scientists believed the iron seeding might create phytoplankton called diatoms, which have a hard silica shell and are not eaten by zooplankton. But because the Southern Ocean was low in the silicic acid needed to make the hard silica shells, regular phytoplankton formed and were consumed before they had a chance to sink.
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