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21 May 2012: Methane Sources Found
Bubbling Up from Melting Ice Caps

U.S. scientists report that they have discovered new sources of methane percolating up from underground reservoirs as glaciers, ice caps, and permafrost melt in the Arctic. University of Alaska researchers, conducting aerial and ground surveys, said they have discovered 150,000 methane seeps in Alaska alone near the margins of retreating glaciers or thawing permafrost. In Greenland, the seeps tended to be concentrated around the margins of ice caps that have been retreating for the past 150 years, the scientists said. Katey M. Walter Anthony, lead author of the study, published in Nature Geoscience, said these seeps in the earth’s frozen zones, or cryosphere, are not currently a major source of methane emissions. But, she added, “As the cryosphere degrades further, it could be a really big source.” Methane is a far more potent greenhouse gas than carbon dioxide, and researchers are concerned rapid warming of the Arctic could trigger a methane “time bomb” as thawing permafrost, vegetation, and land ice result in the release of huge quantities of methane.
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04 May 2012: Greenland Glaciers Moving
More Slowly Than Previous Estimates

A new U.S. study says that Greenland’s glaciers are sliding into the sea more slowly than previously estimated, a finding that may indicate future sea level rise will not be as high as some projected worst-case scenarios. Using satellite data to track changes to 200 outlet glaciers from 2000 to 2011, a team of scientists calculated that Greenland’s glaciers accelerated by an average of 30 percent during the decade — a significant amount but not as rapidly as feared. In an earlier study, scientists calculated that glacial flow would increase by 100 percent between 2000 and 2010, and then stabilize at the higher speed, contributing as much as 19 inches to global sea level rise by the end of the century. According to the new study, published in the journal Science, the glaciers are expected to continue gaining speed in the coming decades, possibly contributing four inches to sea level rise by 2100. The researchers cautioned, however, that a 10-year study is too short to make any conclusions on long-term behavior.
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02 May 2012: Polar Bears Taking Long Swims
In Absence of Summer Sea Ice, Study Says

A six-year study has found that polar bears are capable of swimming great distances when foraging for food, an increasingly critical skill as Arctic sea ice declines in summer. Using GPS collars attached to 52 adult females in the southern Beaufort and Chukchi seas from 2004 to 2009, scientists from the U.S. Geological Survey (USGS) found that about a third of the bears — including some with cubs — completed swims greater than 30 miles. Writing in the Canadian Journal of Zoology, the scientists found that in the case of 50 long-distance swims, the bears traveled an average of 96 miles, swimming from one to 10 days; one bear swam 220 miles. While such stamina will become increasingly important for polar bears as a warming climate makes resting on summer sea ice a less available option, the researchers expressed concern that traveling such great distances takes a greater energy toll on the animals. The study sample was too small to draw conclusions about the fate of entire populations, and it is unclear whether such long swims are a new behavior.
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26 Apr 2012: Warm Ocean Currents Play
Key Role in Melting Antarctic Ice Shelves

Warm ocean currents are melting many of Antarctica’s floating ice shelves from beneath, which in turn is speeding up the flow of land-based glaciers into the ocean and increasing global sea levels, according to a new study. An international team of scientists, led by researchers from the British Antarctic Survey (BAS), used 4.5 million measurements from a satellite-based laser altimeter that precisely measures the changing thickness of ice shelves. Using those readings and other data, the researchers determined that 20 of 54 ice shelves that flow off the Antarctic continent and float on the Southern Ocean are melting and thinning from below. Most of the 20 ice shelves are in West Antarctica, where air and ocean temperatures have been steadily rising in recent years. Along the western Antarctic Peninsula, eight ice shelves have fully or partially collapsed in the past several decades, allowing inland glaciers to surge into the sea. But the study, published in Nature, found that even the thinning of ice shelves, without total collapse, speeds up the flow of inland glaciers, increasing global sea levels.
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24 Apr 2012: European Satellite Provides
Precise Data On Arctic Sea Ice Thickness

The European Space Agency’s (ESA) CryoSat satellite is now providing highly accurate data on the thickness and volume of Arctic Ocean ice. Using a high-resolution synthetic aperture radar that sends down pulses of microwave energy, the satellite can measure the difference between the top of the ice and water in the cracks, or leads, that separate the floes. By measuring the height of the ice above water, which usually represents only one-eighth of total ice thickness, the satellite can provide data on ice thickness to within 10 to 20 centimeters, or 4 to 8 inches. The CryoSat satellite was launched in 2010, and since then scientists have been validating the measurements against other data from plane-based instruments and direct, on-ice measurements. "We now have a very powerful tool to monitor the changes taking place at the poles,” said Volker Liebig, the ESA’s director of Earth Observation.
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12 Apr 2012: Drilling of Arctic Could Pose
Ecological Risks, Lloyd’s Report Warns

A new report by Lloyd’s of London, the world’s largest specialist insurance market, warns that rapid development of Arctic oil resources threatens to cause huge ecological damage without strict oversight and appropriate risk management. The report, Arctic Opening: Opportunity and Risk in the High North, projects that as much as $100 billion ((£63 billion) will be invested in the Arctic region over the next decade as the melting of sea ice opens up vast areas to oil and gas exploration and creates new shipping routes. And while this phenomenon will create significant business opportunities, the report says it is “highly likely” that it will also further disturb ecosystems already stressed by climate change and create risks associated with oil spills, particularly in ice-covered areas. “The resilience of the Arctic’s ecosystems in terms of withstanding risk events is weak, and political sensitivity to a disaster is high,” a summary of the report on the Lloyd’s website says. “As a result, companies operating in the Arctic face significant reputational risk.”
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05 Apr 2012: End of Last Ice Age
Driven by Surge in CO2, Study Says

Large releases of carbon dioxide, primarily from oceans in the Southern Hemisphere, were the main factor in ending the last Ice Age, according to a study that confirms the key role of CO2 in warming the planet. Researchers from Harvard and Oregon State University collected 80 samples from ice and sea sediment cores to reconstruct CO2 and temperature levels as the last Ice Age ended beginning about 20,000 years ago. Previously, ice cores from Antarctica showed temperatures rising on that continent before CO2 levels started to climb, leading global warming skeptics to contend that CO2 was not the main driver of warming. But the new study, published in Nature, says that Antarctica was an anomaly and that the global ice and sediment cores unequivocally show that CO2 rose first, which then sparked temperature increases of 6 degrees F. The initial trigger to the end of the Ice Age was a change in the tilt of the Earth’s axis, which warmed land masses in the Northern Hemisphere and melted Arctic Ice, releasing huge amounts of cold, fresh water that changed global ocean circulation. That in turn warmed the Southern Hemisphere, which melted sea and terrestrial ice there, releasing CO2 trapped under the ocean and land, the study said.
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29 Mar 2012: Shell’s Spill Response Plan
For the Beaufort Sea Is Approved by U.S.

The U.S. Department of the Interior has approved Shell Oil’s plan to respond to an oil spill in the Arctic’s Beaufort Sea, clearing the way for exploratory drilling this summer. The decision follows similar U.S. government approval for a spill response plan in the Chukchi Sea, and Shell said that separate exploratory drilling ships will begin working in the two seas off Alaska when ice melts this summer. Shell’s response plan calls for the exploratory vessels to be accompanied by more than a dozen ships that will carry oil-soaking skimmers and booms, as well as a capping stack that could be lowered into the ocean to control a blowout. The Interior Department estimates that 26.6 billion barrels of recoverable oil and 130 trillion feet of natural gas lie under the continental shelf off Alaska. But environmental groups criticized the Interior Department for approving Shell’s spill response plans, saying there is no viable way to clean up an oil spill in the extreme, icy conditions of the Arctic Ocean.
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06 Mar 2012: Humans Carrying Seeds
Pose Threat to Antarctic Native Plants

The tens of thousands of tourists, scientists, and support personnel who visit Antarctica every year are carrying with them large numbers of seeds from alien plants that could one day pose a threat to Antarctica’s limited array of native plant species. A team of scientists vacuumed the clothes and luggage of 850 visitors to Antarctica during the 2007-2008 summer season, finding more than 2,600 stowaway seeds from other regions of the world, including the Arctic and the Alps. That season, 33,000 tourists and 7,000 scientists and support personnel visited Antarctica, carrying with them an estimated 70,000 seeds, according to a study published in the Proceedings of the National Academy of Sciences. The Antarctic continent only has two native species of vascular plants (a hair grass and a pearl wort), and so far scientists have discovered no alien plant species that have taken hold there. The study noted, however, that invasive species such as dandelions have taken root on some sub-Antarctic islands, and that as Antarctica continues to warm, alien species could eventually begin growing on the continent proper.
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01 Mar 2012: NASA Images Depict
Rapid Loss of Thick Arctic Sea Ice

A new comparison of satellite images from 1980 and 2012 vividly depicts the rapid disappearance of thick, multi-year Arctic Ocean ice in winter. Over the past three decades, the extent of the Arctic’s thickest ice has declined by 15 to 17 percent per decade, according to NASA climate scientist Joey Comiso. Using passive microwave sensors and other technology from NASA and U.S. Defense Department satellites, Comiso has shown that the thickest Arctic sea ice — formed over many years — has gone from covering most of the Arctic basin in winter to covering only about a third of the basin. In the images (above), which are based on data collected from November 1 through January 31, multi-year Arctic sea ice is shown in bright white, while thinner ice — often less than two years old — is shown in light blue and milky white. By 2012, thick Arctic sea ice had retreated to an area north of Greenland and Canada’s Arctic Archipelago, according to the images, published in the Journal of Climate.
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29 Feb 2012: Study Finds Level of
Overfishing That Threatens Seabirds

A new study says that seabirds experience a precipitous drop in birth rates when fish supplies dip beneath one-third of maximum levels, a finding that could provide critical insight into how overfishing imperils numerous bird species. In an analysis of research conducted on 14 bird species — from seagulls to penguins — in seven different ecosystems worldwide, an international team of scientists found that over long periods of time the ecosystems consistently followed the same basic law: When the amount of prey fish falls beneath that critical tipping point, the birds produce fewer offspring. The researchers selected only seabirds that feed on sardines, anchovies, herrings and other small fish targeted by fishermen and currently under threat. Those small fish, which are increasingly used to make meal and oil for fish farming, comprise about 30 percent of the global catch. The study, coordinated by Philippe Cury of the University of British Columbia, was published in the journal Science.
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22 Feb 2012: Near-Extinct Penguin Rookery
Recovers with Impressive Genetic Diversity

A century ago, a rookery of roughly 3 million king penguins on sub-Antarctic Macquarie Island was nearly wiped out as a New Zealand blubber merchant boiled the birds to extract oil for lamps. Saved by one of the first international wildlife campaigns, the 4,000 remaining penguins on Macquarie Island have rebounded to 500,000 birds, and new genetic tests show that the population’s genetic diversity is close to pre-slaughter levels. Tim Heupink of Griffith University in Australia compared DNA from 17 penguins today with that from the bones of 1,000-year-old penguins dug up on the island. He found that the recovered population of king penguins is nearly as genetically diverse as the older population, offering hope that other beleaguered populations of birds and mammals can regain not just their numbers but also their genetic diversity. “It is remarkable that a nearly extinct population has recovered levels of past genetic diversity in only 80 years,” said Heupink, whose study was published in the journal, Biological Letters.
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14 Feb 2012: Unique Antarctic Fish
Threatened by Warming Southern Ocean

A unique group of fish that has evolved to live in Antarctic waters thanks to “anti-freeze” proteins in their blood and body fluids is threatened by rising temperatures in the Southern Ocean, according to a new study. Yale University researchers say that the more than 100 species of so-called icefish, or notothenioids, evolved 20 million to 40 million years ago to live in waters as low as -2 degrees C, which is the freezing point of saltwater. The notothenioids account for the bulk of fish diversity in the waters around Antarctica and are an important source of food for penguins, seals, and toothed whales. But as water temperatures rise in the Southern Ocean — some Antarctic water temperatures have increased by .5 degrees C in the past several decades — the notothenioids may have trouble adapting to a warmer environment, said the study, published in the Proceedings of the National Academy of Science. “A rise of 2 degrees centigrade of water temperature will likely have a devastating impact on this Antarctic fish lineage,” said Thomas Near, associate professor of ecology and evolutionary biology at Yale.
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09 Feb 2012: Glaciers, Ice Caps Losing
150 Billion Tons of Ice Annually

A new analysis of global satellite data has found that the world’s glaciers and ice caps — excluding Antarctica and Greenland — lost about 150 billion tons of ice per year between 2003 and 2010, adding about 0.4 millimeters to global sea rise annually. Using data from the twin Gravity Recovery and Climate Experiment (GRACE) satellites, researchers at the University of Colorado-Boulder compiled what they say is the most comprehensive data on planetary ice loss. The satellites, which are part of a joint project between NASA and Germany, travel around Earth in tandem 16 times a day and are capable of sensing subtle variations in the planet’s mass and gravitational pull. While the new calculations are significantly lower than earlier land-based studies, the researchers say the findings still show the planet’s ice is melting and causing sea levels to rise. “These new results will help us answer important questions in terms of both sea rise and how the planet’s cold regions are responding to global change,” said John Wahr, a CU-Boulder physics professor and lead author of the study, published in Nature.
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08 Feb 2012: Russian Scientists Confirm
They Have Reached Ancient Antarctic Lake

Russian researchers say they have drilled through more than 2 miles of ice on Antarctica’s polar plateau and reached an ancient subglacial lake that has been sealed off for as many as 15 million years. Reaching the lake caps a two-decade drilling effort at Russia’s Vostok Station in Antarctica, which in 1982 recorded Earth’s coldest temperature of -129 degrees F. The chief of the Vostok Station, A.M. Yelagin, confirmed in a statement that Russia’s drilling team had reached the lake on Sunday, when water shot up from 12,365 feet below the surface and froze as it reached the -67 degree F air. Scientists are hoping that the lake could contain a wide variety of evolutionary secrets, including evidence of previously unknown prehistoric life forms. But Russian researchers said that clean water samples from the lake will not be taken until the next Antarctic summer, in December, since the water released over the weekend was contaminated by drilling fluids. Vostok is also the site of some of the deepest ice core samples ever taken on earth, revealing 800,000 years of climate data.
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23 Jan 2012: A Snowy Owl Boom
Is Hitting the Northern U.S. This Winter

Wildlife experts say an unprecedented number of snowy owls have ventured south into the northern U.S. this winter, a spike that may be driven by a dearth of food in the Arctic. From Seattle to Boston, bird-watchers have spotted the owls — marked by bright white plumage — in rarely seen numbers, Denver Holt, director of the U.S.-based Owl Research Institute, told the New York Times. In late November, Holt said, one owl was even spotted at an airport in Hawaii, the first reported sighting in that state. While the birds typically fly south in large numbers during the late fall — and stick around until March or April — researchers say this year’s movement has been massive. According to Holt, the species had a good breeding year and access to an ample food supply last year, including lemmings, which comprise 90 percent of its Arctic diet. But other ornithologists speculate that lemming populations have crashed recently, although scientists have not confirmed such a decline, the Times reports.
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18 Jan 2012: Warming Temperatures Help
Trumpeter Swans Thrive, Study Says

The trumpeter swan, nearly hunted to extinction across much of North America during the 19th century, has experienced a strong resurgence with the help of a warming climate, U.S. researchers say. The large bird, which depends on long summers for breeding, has expanded its summer range northward since the late 1960s into habitat that had previously been inaccessible, according to a new study published in the journal Wildlife Biology. The swan, which can have an 8-foot wingspan, requires 145 ice-free days to adequately raise its young. With warming temperatures, particularly in Alaska and northern Canada, the birds are gaining more nesting habitat than they are losing, researchers say. “In warmer periods, there are more pairs observed occupying the summer breeding habitat than in colder periods,” said Joshua Schmidt, a wildlife biologist with the National Park Service and lead author of the study. The authors of the new study warn that these changes in species distribution could create greater competition between species for breeding areas.
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04 Jan 2012: Teeming Ecosystem Found
Near Vents in Southern Ocean

Researchers exploring deep-sea hydrothermal vents near Antarctica in the Southern Ocean say they have discovered an ecosystem teeming with life, including hundreds of hairy-chested yeti crabs, stalked barnacles, and what could be a new species of octopus. Using a remotely operated vehicle to scan the sea bed near the East Scotia Ridge, located several miles under the ocean’s surface, a team of British scientists observed hundreds of yeti crabs clustered near the vents, where the water can reach temperatures of 752 degrees F (400 degrees C). Unlike yeti crabs discovered previously near hydrothermal vents in the South Pacific, these new crabs were found in greater numbers and had mats of hair covering their undersides, said Alex Rogers, an Oxford University researcher and lead author of the study published in the journal PLoS ONE. The researchers also photographed a pale octopus they say could be a new species related to Vulcanoctopus hydrothermalis, which has been found at other vents around the world. “The animals existing at these vents are almost all new to science,” Rogers said.
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13 Dec 2011: Huge Methane Plumes
Are Discovered in Arctic Ocean

Russian scientists sampling the waters of the East Siberian Arctic Shelf have discovered enormous plumes of methane, some more than a kilometer wide, bubbling up from the thawing seabed. Igor Semiletov, an oceanographer from the Russian Academy of Sciences, said a research cruise late this summer detected more than 100 of these extensive methane “fountains” in an area of less than 10,000 square miles. Semiletov, who has been studying the region’s seabed for 20 years, said the scale and volume of the plumes far surpasses anything he had seen previously and could indicate that slushy methane hydrates on the seabed are thawing at an intensifying rate as Arctic Ocean ice disappears and sea temperatures rise. In 2010, Semiletov estimated that the emissions of methane — a powerful heat-trapping gas — bubbling from the seabed in this region were about 8 million tons a year, but he said the recent expedition has shown that methane releases could be far higher. “We carried out checks at about 115 stationary points and discovered methane fields of a fantastic scale,” Lemiletov told the UK’s Independent.
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05 Dec 2011: Hidden Contours of Antarctica
Depicted in Map of ‘Ice-free’ Continent

Scientists with the British Antarctic Survey have published the most detailed map yet of what Antarctica’s landscape would look like without its thick covering of ice, showing that large portions of the frozen continent actually rest on the sea bed rather than on land. Using data collected by aerial flights, satellite technology, and research ships over 50 years, British researchers were able to illustrate mountain peaks that are the size of the European Alps but are hidden below thousands of feet of ice. Less than 1 percent of the continent’s rock base is currently visible above the ice, which is three miles thick in places. Known as BEDMAP, the imagery will be shown at a meeting of the American Geophysical Union this week. With increasing evidence that Antarctica's edges are warming faster than anywhere else on Earth, the new imagery could help scientists forecast future melting.
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