Until Between 6 to 10 Million Years ago, the Arctic was ice Free During Summer

An international team of scientists led by the Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research (AWI) have managed to open a new window into the climate history of the Arctic Ocean. Using unique sediment samples from the Lomonosov Ridge, the researchers found that six to ten million years ago the central Arctic was completely ice-free during summer and sea-surface temperature reached values of 4 to 9 degrees Celsius. In spring, autumn and winter, however, the ocean was covered by sea ice of variable extent, the scientists explain in the current issue of the journal Nature Communications. These new findings from the Arctic region provide new benchmarks for groundtruthing global climate reconstructions and modelling.

The researchers had recovered these unique sediment samples during an expedition with Germany's research icebreaker RV Polarstern in summer of 2014. "The Arctic sea ice is a very critical and sensitive component in the global climate system. It is therefore important to better understand the processes controlling present and past changes in sea ice. In this context, one of our expedition's aims was to recover long sediment cores from the central Arctic, that can be used to reconstruct the history of the ocean's sea ice cover throughout the past 50 million years. Until recently, only a very few cores representing such old sediments were available, and, thus, our knowledge of the Arctic climate and sea ice cover several millions of year ago is still very limited," Prof. Dr. Ruediger Stein, AWI geologist, expedition leader and lead author of the study, explains.

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North Pole Experienced 4 C (40 F) This Week, in the Dead of Winter

A weather anomaly sweeping across the world could cause temperatures at the North Pole to reach nearly 4 C this week.

Texas, Australia and England are just a few of the regions that have seen a spate of extreme weather this month, including tornadoes, brush fires and flooding. Now, forecasters say the North Pole is seeing temperatures well above normal.

CBC North's resident meteorologist, Ashley Brauweiler, says the severe weather system that wreaked havoc in the U.S. and beyond is the reason.

"We have temperatures above zero near the poles and that's because the jet stream is bringing that warm air from the south up and along Greenland and Iceland. While storms here are normal, the strength of the storm isn't," Brauweiler said.

"They're seeing the same storms that were affecting the southern [U.S.] states."

At the North Pole on Thursday, temperatures are expected to hit 3 C. On New Year's Day it will be nearly 4 C.

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The North Pole, in the darkest time of the year, experienced warmer temperatures than parts of the SF Bay Area in California at night.  Consider that for a moment.

hat tip to Randy.

Reconstructing the Paleohydrology of a Cretaceous Alaskan Paleopolar Coastal Plain

Reconstructing the paleohydrology of a cretaceous Alaskan paleopolar coastal plain from stable isotopes of bivalves

Authors:

Suarez et al

Abstract:

As global mean annual temperatures continue to rise, modern Arctic climates are changing at an incredibly fast rate. To predict changing climate dynamics, a number of researchers have been focused on characterizing Arctic climate from ancient greenhouse worlds such as the Cretaceous and Eocene. Characterization of these climates requires analysis of a variety of proxy materials. Here we use bivalve shells, identified as Nucula aff. Nucula percrassa Conrad, from the Cretaceous (early Maastrichtian) Prince Creek Formation in combination with isotope data from previous lithologic and isotopic studies to characterize a cool-house Cretaceous climate bounded by greenhouse climates (mid-Cretaceous thermal maximum and Late Paleocene climate). Bivalves were analyzed by powder X-ray diffraction (PXRD), cathodoluminescence (CL), and thin section petrography to determine mineralogy and integrity of shells. PXRD analysis indicates that shells are composed of primary aragonite and not secondary calcite. Thin section and CL images reveal well preserved shell morphology including daily growth lines, and no luminescent patches or coarsening of crystal sizes to indicate diagenetic alteration/recrystallization. Aragonite carbon isotopic composition (δ13Carag) range from + 0.45‰ to − 3.00‰ VPDB and average − 1.58‰. Aragonite oxygen isotopic composition (δ18Oarag) range from − 10.48‰ to − 15.42‰ VPDB and average − 12.83‰. Using temperatures from 4.5 °C to 12.5 °C, the salinity–δ18Owater relationship of a modern Arctic setting from Torres et al. (2011), and the water–aragonite equation of Grossman and Ku (1986) reveal salinity ranges between 8 and 17.7 ppt. Using these salinity ranges and temperatures, N. percrassa precipitated shell aragonite from water that ranged between δ18Owater = − 14.41‰ VSMOW (at 12.5 °C) and − 16.23‰ (at 4.5 °C). Shell growth was in equilibrium with water that represents a coastal, mixed water setting such as an estuary. When combined with previous studies, the mixture of fresh:marine water represents a 50%:50% to 72%:28% mixture and ranged between − 14.41‰ and − 16.23‰ during spring to summer months.

Crayfish Burrows From Maastrichtian Cretaceous Alaska Suggest PaleoTemperature Range Between -6 C to 28C

Crayfish burrows from the latest Cretaceous lower Cantwell Formation (Denali National Park, Alaska): Their morphology and paleoclimatic significance

Authors:

Fiorillo et al

Abstract:

Latest Cretaceous strata of the lower Cantwell Formation, Denali National Park, central Alaska Range, contain an abundance of megafloral remains and invertebrate and vertebrate trace fossils. Though dominated by herbivorous dinosaur footprints, the abundance and diversity of fossil bird tracks are unique. We present newly discovered crayfish burrows from several areas along a 50 km transect with Denali National Park. Most crayfish burrows from the lower Cantwell Formation are preserved only in cross-section and range from approximately 5–10 cm in diameter. Where preserved in full relief and terminations present, burrow depth is generally less than 50 cm. Burrow morphology is similar to burrow morphology of modern freshwater crayfish (Cambaridae).

The Cantwell Formation fills the Cantwell Basin, a 135 km-long and up to 35 km-wide, east–west trending basin, bracketed by the Hines Creek Fault to the north and the McKinley Fault to the south. Basin fill comprises up to 4000 m of continental deposits, interpreted as braided rivers, alluvial fans, floodplains, swamps, and ponds.

Crayfish burrows provide evidence of water table level, soil moisture fluctuations, as well as insight into mean annual temperatures at the time of deposition of the lower Cantwell Formation, a Late Cretaceous high-latitude paleoecosystem. Despite a relatively high latitudinal setting (~ 71°N paleolatitude), the Late Cretaceous (i.e., Campanian–Maastrichtian) mean annual temperature, based on the distribution of similar present-day crayfish burrows, was more like that of southernmost Ontario, Canada, where the northernmost burrowing crayfish are found today. The burrow depth suggests (1) no permafrost was present, and (2) the phreatic zone was ~ 30–50 cm below the paleo-ground surface. Based on the presence of these crayfish burrows, the paleoclimate is interpreted as humid continental (Köppen scheme), with average summer high temperatures between 25 °C and 28 °C and average winter low temperatures between − 6 °C and 0 °C. These estimates compare somewhat favorably with previous CLAMP estimates of a warm monthly mean temperature of 17.08 +/− 1.6 °C and a cold monthly mean temperature of − 2.31 +/− 1.9 °C.

Terrestrial Evidence for a Middle-Maastrichtian Cretaceous Warming Event in Alaska

Terrestrial isotopic evidence for a Middle-Maastrichtian warming event from the lower Cantwell Formation, Alaska

Authors:

Salazar-Jaramillo et al

Abstract:

Carbon stable isotope data (δ13C) and new radiometric dates indicate that the non-marine Late Cretaceous lower Cantwell Formation, central Alaska, registers the Middle-Maastrichtian Event (MME), a global warming episode. A stratigraphic section measured at the East Fork of the Toklat River in Denali National Park & Preserve includes a bentonite layer that we have dated to 69.5 ± 0.7 Ma using U–Pb isotope analysis of zircons. The new depositional age confirms that dinosaur tracks from the lower Cantwell Formation are coeval with dinosaur bones from outcrops of the Prince Creek Formation on Alaska's North Slope. δ13C data from fossil wood recovered from the lower Cantwell Formation records an ~ 3‰ positive excursion correlative with positive excursions from terrestrial and marine sections in West Texas (USA) and Gubbio (Italy), respectively. The similarity between marine and terrestrial records suggests that this excursion is the result of a major perturbation in the global carbon cycle, known as the Middle-Maastrichtian Event (MME). Mean annual precipitation (MAP) estimates calculated from δ13C data yield a range of 168–470 mm/yr during the MME, 353–1050 mm/yr before and 475–1451 mm/yr after the warming event. The δ13C record from the lower Cantwell Formation provides the first terrestrial high-latitude evidence for the MME, while MAP estimates for the coeval Prince Creek Formation suggest that the arctic coast may have been more humid than southern interior Alaska during the Middle Maastrichtian.

The Weird World of Alaska's Arctic Dinosaurs

During Patrick Druckenmiller's not-so-restful sabbatical year, he is flying to museums around the world. In Alberta a few weeks ago and London now, the University of Alaska Museum's curator of earth science is looking at bones of dinosaurs similar to ones found in northern Alaska. The more he squints at them and chats with experts, the more he thinks far-north dinosaurs are like Alaskans compared to other Americans: kind of the same, but a little off.

"When we really reexamine the fauna, (northern Alaska) is a very weird place," Druckenmiller said.

The mini tyrannosaur, duck-billed swamp-stompers, armor-headed planteaters and other dinosaurs found in northern Alaska hint of a story that is theirs alone. That tale is separate from the one we learned as kids, told by fossils found in Montana, Alberta, Mongolia and other more-exposed and easier-to-get-to places.

Druckenmiller's examinations of the duckbilled dinosaurs found in Alberta led to the recent declaration of a new Alaska hadrosaur species due to slight but significant differences in body structure.

"They're close but they're different," Druckenmiller said. "It's true for fish, dinosaurs and mammals. There's no obvious gene flow between areas."

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The Mean Days of Ice Cover in the Arctic Since 1920 to 2100, historical to projected

Ice was in the news quite a lot last week. There was, for example, the news that Antarctica could be gaining, not losing, ice, at least for now.

Lest you were tempted to breathe a sigh of relief, critics pointed to contrary evidence. And there were also these unsettling findings about the gigantic West Antarctic Ice Sheet.

But far to the north, some equally important news unfortunately got less attention. For the long and short of it, see the animation above.

I created it to portray in visual form what a study published last week has revealed: Unless we start reining in greenhouse gas emissions, “our projected impact on the climate system will change the face of Arctic sea ice,” says Katy Barnhart, who led the study while she was at the University of Colorado’s Institute for Arctic and Alpine Research. (Full disclosure: I’m a professor at the University of Colorado.)

The animation shows computer model simulations of how Arctic sea ice is likely to respond to continued human-caused warming. More specifically, it models how the number of days of open water change each year from 1920 to 2100 under a “business-as-usual” scenario. By 2100, according to the study, much of the Arctic has greater than 150 additional days of open water as compared with the pre industrial period prior to 1850.

But we won’t have to wait that long to see significant changes. If greenhouse gas emissions continue to rise, the entire coastline of the Arctic, and most of the Arctic Ocean itself, will see at least 60 additional days a year of open water by mid-century. Some sites will even see 100 additional open water days.

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The Environment of the High Arctic During the Late Cretaceous

Environmental Constraints on Terrestrial Vertebrate Behaviour and Reproduction in the High Arctic of the Late Cretaceous

Authors:

Herman et al

Abstract:

Reconstructions of temperature and moisture regimes based on fossil leaves, combined with tree ring studies, detail the light regime, length of the growing season, and summer and winter temperatures of the Late Cretaceous Arctic. Such constraints have important implications for dinosaur feeding and reproductive behaviour, and the capacity to reside year-round in near-polar environments.

At the highest palaeolatitudes where dinosaurs have been found (82-85 °N) winter darkness lasted for ~ 120 days and the spring and autumn twilight periods for ~ 15 days. A mostly cloud and mist-shrouded environment witnessed a mean annual temperature (MAT) of 6-7 °C, a warm month mean temperature (WMMT) of 14.5 ± 3.1 °C and a cold month mean temperature (CMMT) of -2 ± 3.9 °C. Growth rings in wood suggest summer temperatures frequently fell below + 10 °C. Winter temperatures as low as -10 °C were likely for short periods. Spring bud break in late February to early March and leaf fall in early October limited the time when fresh food was available in any quantity to not more than 6 months.

The diversity of Arctic dinosaur body sizes implies a range of overwintering strategies but year-round residency requires reproduction. Burrowing and enclosed nest building no doubt facilitated overwintering for small animals, but for larger dinosaurs shelter was problematical. No dinosaur egg remains have yet been found as far north as 82° palaeolatitude, but they occur 6° further south in the Early Maastrichtian Kakanaut Formation, Northeastern Russia. Here the winter darkness was shorter (45 days), and the temperature regime warmer (MAT 10 °C, WMMT 19 °C, CMMT + 3 °C). The growing season (temperatures greater than 10 °C) was ~ 6.3 months and fresh food was available in quantity for slightly longer. These summer temperatures constrain the thermal regime of nest environments and suggest sophisticated nest management and possibly brooding strategies for the necessary rapid incubation and hatching before the onset of winter.

Yours, Mine and Moscow's: Russian Arctic Claims

On August 4th, the Russian Federation’s Foreign Ministry reported that it had resubmitted its claim to a vast swath (more than 1.2 million square kilometers, including the North Pole) of the rapidly changing and potentially lucrative Arctic to the United Nations. In 2002, Russia put forth a similar claim, but it was rejected based on lack of sufficient support. This latest petition, however, is supported by “ample scientific data collected in years of arctic research,” according to Moscow. Russia’s latest submission for the United Nation’s Commission on the Limits of the Continental Shelf’s (CLCS) consideration coincides with increased Russian activity in the High North, both of a military and economic nature. Recent years have seen Russia re-open a Soviet-era military base in the remote Novosibirsk Islands (2013), with intentions to restore a collocated airfield as well as emergency services and scientific facilities. According to a 2015 statement by Russian Deputy PM Dmitry Rogozin, the curiously named Academic Lomonsov, a floating nuclear power plant built to provide sustained operating power to Arctic drilling platforms and refineries, will be operational by 2016. Though surely the most prolific in terms of drilling and military activity, Russia is far from the only Arctic actor staking their claim beyond traditional EEZs in the High North. Given the increased activity, overlapping claims, and dynamic nature of Arctic environment as a whole, Russia’s latest claim has tremendous implications, whether or not the United Nations CLCS provides a recommendation in favor of Moscow’s assertions.

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Russia is Claiming a Vast Undersea Territory in the Arctic

Moscow’s occupation and annexation of Crimea has attracted enormous attention and much criticism, but its efforts to get the international community to declare a much larger area of the Arctic Ocean Russian coastal waters and thus an exclusion zone have not.

That may be about to change. Moscow has just filed a revised request with the International Commission on Continental Shelf Boundaries, a UN body, and asked that the commission grant Russian the right to an economic exclusion zone in the Arctic far beyond the current 350 miles from its shores.

The Russian government made a similar request in 2001, but after three years of study and controversy with the other Arctic powers – Norway, Denmark, Canada and the United States – the commission rejected that application. Now, on what it says is new research over the last decade, Moscow is applying again.

The Russian argument is that various undersea mountains and plateaus are part of its continental shelf and therefore naturally part of its coastal waters. But the other Arctic powers and others, including China, have disputed that, arguing that these subsea features are separate and independent from any continental shelf.

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A 4 Celsius Cold Snap in the Aptian/Albian Cretaceous High Arctic

Mid-Cretaceous High Arctic stratigraphy, climate, and Oceanic Anoxic Events

Authors:

Herrie et al

Abstract:

Over the past decades, much research has focused on the mid-Cretaceous greenhouse climate, the formation of widespread organic-rich black shales, and cooling intervals from low- to mid-latitude sections. Data from the High Arctic, however, are limited. In this paper, we present high-resolution geochemical records for an ∼1.8-km-thick sedimentary succession exposed on Axel Heiberg Island in the Canadian Arctic Archipelago at a paleolatitude of ∼71°N. For the first time, we have data constraints for the timing and magnitude of most major Oceanic Anoxic Events (OAEs) in brackish-water (OAE1a) and shelf (OAE1b and OAE2) settings in the mid-Cretaceous High Arctic. These are consistent with carbon-climate perturbations reported from deep-water records of lower latitudes. Glendonite beds are observed in the upper Aptian to lower Albian, covering an interval of ∼6 m.y. between 118 and 112 Ma. Although the formation of glendonites is still under discussion, these well-dated occurrences may support the existence of cool shelf waters in the High Arctic Sverdrup Basin at this time, coeval with recent geochemical data from the subtropical Atlantic indicating a drop in sea-surface temperature of nearly 4 °C.

Phytoplankton Amplifying Arctic Greenhouse Warming

Amplified Arctic warming by phytoplankton under greenhouse warming

Authors:

Park et al

Abstract:

Phytoplankton have attracted increasing attention in climate science due to their impacts on climate systems. A new generation of climate models can now provide estimates of future climate change, considering the biological feedbacks through the development of the coupled physical–ecosystem model. Here we present the geophysical impact of phytoplankton, which is often overlooked in future climate projections. A suite of future warming experiments using a fully coupled ocean−atmosphere model that interacts with a marine ecosystem model reveals that the future phytoplankton change influenced by greenhouse warming can amplify Arctic surface warming considerably. The warming-induced sea ice melting and the corresponding increase in shortwave radiation penetrating into the ocean both result in a longer phytoplankton growing season in the Arctic. In turn, the increase in Arctic phytoplankton warms the ocean surface layer through direct biological heating, triggering additional positive feedbacks in the Arctic, and consequently intensifying the Arctic warming further. Our results establish the presence of marine phytoplankton as an important potential driver of the future Arctic climate changes.

DNA Testing Suggests Alaska's North Slope was Ancient Homeland for PreColumbian Arctic North American Peoples

Genetic testing of Iñupiat people currently living in Alaska's North Slope is helping Northwestern University scientists fill in the blanks on questions about the migration patterns and ancestral pool of the people who populated the North American Arctic over the last 5,000 years.

"This is the first evidence that genetically ties all of the Iñupiat and Inuit populations from Alaska, Canada and Greenland back to the Alaskan North Slope," said Northwestern's M. Geoffrey Hayes, senior author of the new study to be published April 29, 2015, in the American Journal of Physical Anthropology.

In this study, all mitochondrial DNA haplogroups previously found in the ancient remains of Neo- and Paleo-Eskimos and living Inuit peoples from across the North American Arctic were found within the people living in North Slope villages.

These findings support the archaeological model that the "peopling of the eastern Arctic" began in the North Slope, in an eastward migration from Alaska to Greenland. It also provides new evidence to support the hypothesis that there were two major migrations to the east from the North Slope at two different times in history.

"There has never been a clear biological link found in the DNA of the Paleo-Eskimos, the first people to spread from Alaska into the eastern North American arctic, and the DNA of Neo-Eskimos, a more technologically sophisticated group that later spread very quickly from Alaska and the Bering Strait region to Greenland and seemed to replace the Paleo-Eskimo," Hayes said.

"Our study suggests that the Alaskan North Slope serves as the homeland for both of those groups, during two different migrations. We found DNA haplogroups of both ancient Paleo-Eskimos and Neo-Eskimos in Iñupiat people living in the North Slope today."

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There was a 4 C Temperature Drop at High Latitude During the Valanginian Cretaceous

Latitudinal temperature trends in the northern hemisphere during the Early Cretaceous (Valanginian - Hauterivian)

Authors:

Meissner et al

Abstract:

We present the first detailed stable isotope record (δ13C, δ18O) for the Valanginian (Lower Cretaceous) of the southern Boreal Realm. The observations are based on the geochemical analysis of 286 belemnite rostra from stratigraphically well-dated sections in northwest Germany. A major positive carbon isotope excursion (CIE) of ~ 2‰ in the early late Valanginian documents a perturbation of the carbon cycle. This positive CIE, which is well known as the 'Weissert Event' in the Tethys, is also displayed in composite carbon isotope records based on published and own data from three different palaeolatitudes (35°, 39°, 65° North). These findings suggest that the environmental changes indicated by the CIE in the early late Valanginian are synchronous, thereby pointing to a global control. The combined oxygen isotope data sets show long-term fluctuations of up to 7 °C with a cooling in the late Valanginian for both the southern and the arctic part of the Boreal Realm, while Tethyan data document only a ca. 1 °C cooling. Based on a reliable bio- and chemostratigraphic correlation between the different realms this study highlights the amplitude of the environmental perturbations in the Valanginian and supports the idea that a combination of regional and global factors caused such shifts.

Russia Warns NATO Away From Arctic Involvement

There were no emerging problems in Arctic that require NATO involvement and, “moreover, there are no problems there which demand military decisions,” Russia’s foreign minister Sergei Lavrov said in a foreign policy lecture on Monday.

“We firmly believe that there are no problems in the Arctic which demand NATO participation,” he said according to a report in the ITAR TASS news agency.

“The Arctic is a territory of dialogue… We use this slogan for regular forums in Russia, and the work of the Arctic Council, to a large extent, is drawn up in this way.”

[...]

However, despite Lavrov’s comments, Russia is currently reestablishing a robust military presence in the Arctic.

Russia has reactivate[d] ten bases on its northern border to protect its claims in the region and stood up a new Northern Fleet-Unified Strategic Command earlier this year.

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Methanoflorens stordalenmirensis: A Potentially Potent Microbial Amplipher to Anthropogenic Global Warming

Tiny soil microbes are among the world's biggest potential amplifiers of human-caused climate change, but whether microbial communities are mere slaves to their environment or influential actors in their own right is an open question. Now, research by an international team of scientists from the U.S., Sweden and Australia, led by University of Arizona scientists, shows that a single species of microbe, discovered only very recently, is an unexpected key player in climate change.

The findings, published in the journal Nature, should help scientists improve their simulations of future climate by replacing assumptions about the different greenhouse gases emitted from thawing permafrost with new understanding of how different communities of microbes control the release of these gases.

Earlier this year, the international team discovered that a single species of microbe, previously undescribed by science, was prominent in permafrost soils in northern Sweden that have begun to thaw under the effect of globally rising temperatures. Researchers suspected that it played a significant role in global warming by liberating vast amounts of carbon stored in permafrost soil close to the Arctic Circle in the form of methane, a powerful greenhouse gas trapping heat in the Earth's atmosphere. But the actual role of this microbe — assigned the preliminary name Methanoflorens stordalenmirensis, which roughly translates to "methane-bloomer from the Stordalen Mire" — was unknown.

The new research nails down the role of the new microbe, finding that the sheer abundance of Methanoflorens, as compared to other microbial species in thawing permafrost, should help to predict their collective impact on future climate change.

"If you think of the African savanna as an analogy, you could say that both lions and elephants produce carbon dioxide, but they eat different things," said senior author Scott Saleska, an associate professor in the UA's Department of Ecology and Evolutionary Biology and director of the UA's new Ecosystem Genomics Institute. "In Methanoflorens, we discovered the microbial equivalent of an elephant, an organism that plays an enormously important role in what happens to the whole ecosystem."

Significantly, the study revealed that because of these microbial activities, all wetlands are not the same when it comes to methane release.

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Increased Arctic Planet Growth Increases High Latitude Warming

Increased carbon dioxide in the atmosphere is known to boost vegetation cover at high latitudes — and this could accelerate Arctic warming year-round.

Grasses and shrubs have a warming effect because plant-covered areas reflect less sunlight than barren surfaces do. Baek-Min Kim at the Korea Polar Research Institute in Incheon, South Korea, Sang-Yoon Jun at the Korea Institute of Atmospheric Prediction Systems in Seoul and their colleagues used a climate model to study the impact of doubled CO2 concentrations and increased high-latitude plant growth on Arctic temperatures.

They found that increased vegetation in summer warms the surface and this heat moves to the Arctic, where it causes additional ocean warming and sea-ice melting in winter and spring. The exposed ocean then releases more heat, leading to a further boost in Arctic warming and promoting even more plant growth the following season, the team says.

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2014 the 6th Lowest Arctic Sea Ice Level Measured

Arctic sea ice coverage continued its below-average trend this year as the ice declined to its annual minimum on Sept. 17, according to the NASA-supported National Snow and Ice Data Center (NSIDC) at the University of Colorado, Boulder.

Over the 2014 summer, Arctic sea ice melted back from its maximum extent reached in March to a coverage area of 1.94 million square miles (5.02 million square kilometers), according to analysis from NASA and NSIDC scientists. This year's minimum extent is similar to last year's and below the 1981-2010 average of 2.40 million square miles (6.22 million square km).

"Arctic sea ice coverage in 2014 is the sixth lowest recorded since 1978. The summer started off relatively cool, and lacked the big storms or persistent winds that can break up ice and increase melting," said Walter Meier, a research scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland.

"Even with a relatively cool year, the ice is so much thinner than it used to be," Meier said. "It's more susceptible to melting."

This summer, the Northwest Passage above Canada and Alaska remained ice-bound. A finger of open water stretched north of Siberia in the Laptev Sea, reaching beyond 85 degrees north, which is the farthest north open ocean has reached since the late 1970s, according to Meier.

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Even ice Covered Arctic Sea Absorbs Carbon dioxide

Due to global warming, larger and larger areas of sea ice melt in the summer and when sea ice freezes over in the winter it is thinner and more reduced. As the Arctic summers are getting warmer we may see an acceleration of global warming, because reduced sea ice in the Arctic will remove less CO2 from the atmosphere, Danish scientists report.

"If our results are representative, then sea ice plays a greater role than expected, and we should take this into account in future global CO2 budgets", says Dorte Haubjerg Søgaard, PhD Fellow, Nordic Center for Earth Evolution, University of Southern Denmark and the Greenland Institute of Natural Resources, Nuuk.

Only recently scientists have realized that sea ice has an impact on the planet's CO2 balance.

"We have long known that the Earth's oceans are able to absorb huge amounts of CO2. But we also thought that this did not apply to ocean areas covered by ice, because the ice was considered impenetrable. However, this is not true: New research shows that sea ice in the Arctic draws large amounts of CO2 from the atmosphere into the ocean", says Dorte Haubjerg Søgaard.

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Snow on Arctic Ice has Radically Decreased

From research stations drifting on ice floes to high-tech aircraft radar, scientists have been tracking the depth of snow that accumulates on Arctic sea ice for almost a century. Now that people are more concerned than ever about what is happening at the poles, research led by the University of Washington and NASA confirms that snow has thinned significantly in the Arctic, particularly on sea ice in western waters near Alaska.

A new study, accepted for publication in the Journal of Geophysical Research: Oceans, a publication of the American Geophysical Union, combines data collected by ice buoys and NASA aircraft with historic data from ice floes staffed by Soviet scientists from the late 1950s through the early 1990s to track changes over decades.

Historically, Soviets on drifting sea ice used meter sticks and handwritten logs to record snow depth. Today, researchers on the ground use an automated probe similar to a ski pole to verify the accuracy of airborne measurements.

"When you stab it into the ground, the basket move up, and it records the distance between the magnet and the end of the probe," said first author Melinda Webster, a UW graduate student in oceanography. "You can take a lot of measurements very quickly. It's a pretty big difference from the Soviet field stations."

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