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Showing posts with label Arctic. Show all posts
Showing posts with label Arctic. Show all posts

Saturday, June 4, 2011

With Global Warming, Arctic Access Will Diminish by Land but Improve by Sea



Global warming over the next 40 years will cut through Arctic transportation networks like a double-edged sword, limiting access in certain areas and vastly increasing it in others, a new UCLA study predicts.
Arctic shipping routes. 
(Credit: Image courtesy of UCLA)

"As sea ice continues to melt, accessibility by sea will increase, but the viability of an important network of roads that depend on freezing temperatures is threatened by a warming climate," said Scott Stephenson, a UCLA graduate student in geography and the study's lead author.

Winners are expected to be coastal communities, coastal resource-extraction operations, tourism, fishing, and shipping concerns, the researchers say. Potential losers include inland mining and timber operations, inland oil and gas drilling, and smaller inland communities, often inhabited by indigenous peoples. Even northern Canada's famed Tibbitt-Contwoyto "diamond road," said to be the world's most lucrative ice road, is expected to suffer, according to the researchers.

The findings appear in the current issue of the peer-reviewed scholarly journal Nature Climate Change.

"Popular perception holds that climate warming will mean an opening up of the Arctic, but our study shows that this is only partly so," said co-author Laurence C. Smith, a UCLA professor of geography and author of "The World in 2050: Four Forces Shaping Civilization's Northern Future" (Dutton Books, 2010). "Rising maritime access for ships will be severely countered by falling vehicular access on land."

Along with veteran UCLA geographer John A. Agnew, Stephenson and Smith integrated existing accessibility models for the Arctic with the National Center for Atmospheric Research's widely used climate models for the coming century. The researchers averaged month-to-month accessibility rates for two time periods: 2010 to 2014 and 2045 to 2059. They then compared the two scenarios.

With an overall anticipated temperature increase of 3.6 to 6.2 degrees Fahrenheit by 2050 -- and an even sharper increase of 7.2 to 10.8 degrees Fahrenheit in the winter -- climate change is expected to have more dramatic effects in the Arctic than anywhere on Earth.

A major casualty will be temporary ice roads, according to the study. Constructed across frozen ground, lakes, rivers and swampy areas using compacted snow and ice and applied sheets of ice, these roads currently provide access to vast swaths of inland terrain where the construction of all-weather roads is not economically viable.

As a result, all eight countries that border the Arctic -- Canada, Finland, Greenland, Iceland, Norway, Russia, Sweden and the United States -- are expected to experience declines in winter-road land accessibility. Losses in access range from 11 percent to 82 percent, depending on the area, the geographers calculate.

In absolute terms, Canada and Russia stand to lose the most winter-road potential as rising temperatures will prevent up to 400,000 square miles from hardening into potential roadways, the researchers found. By 2020, the Tibbitt-Contwoyto winter road, popularized in the History Channel reality television series "Ice Road Truckers," is projected to lose 17 percent of its eight- to 10-week operating season.

With the losses will come severe delays, as overland travelers are forced to combine vehicular transportation with slower means of travel, such as ferries.

An example provided in the study is a land route from the Northwest Territories capital of Yellowknife to the distant northern Canadian community of Bathurst Inlet. By mid-century, the trip, which now takes 3.8 days is expected to drag out for 6.5 days.

The study looked at accessibility for two-ton vehicles, the equivalent of a standard sedan. Losses are expected to be greater for big rigs, the researchers point out. A future project involves refining the model for a greater range of vehicles.

"Remote communities that rely on winter roads, especially those that are inland, may have to switch to air cargo services, which will dramatically increase the costs of supplies," Stephenson said. "That would make life that much harder in these communities."

By contrast, climate change is expected to breathe new life into coastal communities by increasing shipping throughout the Arctic, especially for Type A vessels, which have limited ice-breaking capabilities. (These vessels are used widely for commercial shipping in the Baltic Sea and northern Canada, but less costly vessels without ice-breaking abilities remain the norm in global shipping today, and their accessibility rates in 2050 are the subject of a future study by the same team.)

By 2050, three of the four major shipping routes will be fully accessible from July to September to Type A vessels, the study predicts. One shipping route is so new that it does not yet have a formal name. Stretching from Rotterdam, the Netherlands, to the Bering Strait, the passage was dubbed the "North Pole Route" by the study's authors.

"If you can imagine taking a boat from Europe directly to Alaska, that would be possible according to our results for the North Pole Route," Smith said.

Also fully accessible will be the Northern Sea Route, which stretches from the small northwestern Russian port of Amderma to the small far eastern Russian port of Provideniya, and the Arctic Bridge, which stretches from the Canadian port town of Churchill to the major Russian port Murmansk, the geographers found. The Arctic Bridge is the only Arctic route that already is reliably open during summer months.

Ironically, the sea route that is not expected to become fully passable for the entire summer is the one for which explorers have held the most hope -- the Northwest Passage. Still, stretching from the small Canadian archipelago community of Iqaluit to the Alaskan coastal town of Nome, the route is expected to become 30 percent more accessible to Type A vessels by 2050, the UCLA geographers calculate.

Greenland, Canada, Russia and the United States will enjoy increased access to their exclusive economic zones -- the offshore waterways to which they have exclusive access for fishing and other resource extraction activities, the study states. Arctic high seas, meanwhile, will become four times more accessible, as approximately 700,000 square miles become newly navigable by Type A vessels.

"This will be good news for global shipping interests, who stand to reap savings by moving cargo through these passages rather than through the Panama Canal, Suez Canal or the Strait of Malacca," Stephenson said.

Tuesday, May 17, 2011

Striking Ecological Impact on Canada's Arctic Coastline Linked to Global Climate Change



Scientists from Queen's and Carleton universities head a national multidisciplinary research team that has uncovered startling new evidence of the destructive impact of global climate change on North America's largest Arctic delta.
Dead vegetation killed by the 1999 storm surge is in stark
contrast to the vegetation along the edges of waterways
that receive regular freshwater (and thus survived the
damage). (Credit: Trevor Lantz, University of Victoria)


"One of the most ominous threats of global warming today is from rising sea levels, which can cause marine waters to inundate the land," says the team's co-leader, Queen's graduate student Joshua Thienpont. "The threat is especially acute in polar regions, where shrinking sea ice increases the risk of storm surges."

By studying growth rings from coastal shrubs and lake sediments in the Mackenzie Delta region of the Northwest Territories -- the scene of a widespread and ecologically destructive storm surge in 1999 -- the researchers have discovered that the impact of these salt-water surges is unprecedented in the 1,000-year history of the lake.

"This had been predicted by all the models and now we have empirical evidence," says team co-leader Michael Pisaric, a geography professor at Carleton. The Inuvialuit, who live in the northwest Arctic, identified that a major surge had occurred in 1999, and assisted with field work.

The researchers studied the impact of salt water flooding on alder bushes along the coastline. More than half of the shrubs sampled were dead within a year of the 1999 surge, while an additional 37 per cent died within five years. A decade after the flood, the soils still contained high concentrations of salt. In addition, sediment core profiles from inland lakes revealed dramatic changes in the aquatic life -- with a striking shift from fresh to salt-water species following the storm surge.

"Our findings show this is ecologically unprecedented over the last millennium," says Queen's biology professor and team member John Smol, Canada Research Chair in Environmental Change and winner of the 2004 NSERC Herzberg Gold Medal as Canada's top scientist. "The Arctic is on the front line of climate change. It's a bellwether of things to come: what affects the Arctic eventually will affect us all."

Since nearly all Arctic indigenous communities are coastal, the damage from future surges could also have significant social impacts. The team predicts that sea ice cover, sea levels and the frequency and intensity of storms and marine storm surges will become more variable in the 21st century.

Other members of the team include Trevor Lantz from the University of Victoria, Steven Kokelj from Indian and Northern Affairs Canada, Steven Solomon from the Geological Survey of Canada and Queen's undergraduate student Holly Nesbitt. Their findings are published in the Proceedings of the National Academy of Sciences.

Research funding comes from the Natural Sciences and Engineering Research Council of Canada (NSERC), the Polar Continental Shelf Program, the Cumulative Impact Monitoring Program, and Indian and Northern Affairs Canada.

Thursday, May 5, 2011

Effects of Climate Change in Arctic More Extensive Than Expected, Report Finds



A much reduced covering of snow, shorter winter season and thawing tundra: The effects of climate change in the Arctic are already here. And the changes are taking place significantly faster than previously thought. This is what emerges from a new research report on the Arctic, presented in Copenhagen this week. Margareta Johansson, from Lund University, is one of the researchers behind the report.
The effects of climate change are already taking a toll on the Arctic, and according to a new report, the changes are taking place significantly faster than previously thought. (Credit: © Martin Schwan / Fotolia)
Together with Terry Callaghan, a researcher at the Royal Swedish Academy of Sciences, Margareta is the editor of the two chapters on snow and permafrost.

"The changes we see are dramatic. And they are not coincidental. The trends are unequivocal and deviate from the norm when compared with a longer term perspective," she says.

The Arctic is one of the parts of the globe that is warming up fastest today. Measurements of air temperature show that the most recent five-year period has been the warmest since 1880, when monitoring began. Other data, from tree rings among other things, show that the summer temperatures over the last decades have been the highest in 2000 years. As a consequence, the snow cover in May and June has decreased by close to 20 per cent. The winter season has also become almost two weeks shorter -- in just a few decades. In addition, the temperature in the permafrost has increased by between half a degree and two degrees.

"There is no indication that the permafrost will not continue to thaw," says Margareta Johansson.

Large quantities of carbon are stored in the permafrost.

"Our data shows that there is significantly more than previously thought. There is approximately double the amount of carbon in the permafrost as there is in the atmosphere today," says Margareta Johansson.

The carbon comes from organic material which was "deep frozen" in the ground during the last ice age. As long as the ground is frozen, the carbon remains stable. But as the permafrost thaws there is a risk that carbon dioxide and methane, a greenhouse gas more than 20 times more powerful than carbon dioxide, will be released, which could increase global warming.

"But it is also possible that the vegetation which will be able to grow when the ground thaws will absorb the carbon dioxide. We still know very little about this. With the knowledge we have today we cannot say for sure whether the thawing tundra will absorb or produce more greenhouse gases in the future," says Margareta Johansson.

Effects of this type, so-called feedback effects, are of major significance for how extensive global warming will be in the future. Margareta Johansson and her colleagues present nine different feedback effects in their report. One of the most important right now is the reduction of the Arctic's albedo. The decrease in the snow- and ice-covered surfaces means that less solar radiation is reflected back out into the atmosphere. It is absorbed instead, with temperatures rising as a result. Thus the Arctic has entered a stage where it is itself reinforcing climate change.

The future does not look brighter. Climate models show that temperatures will rise by a further 3 to 7 degrees. In Canada, the uppermost metres of permafrost will thaw on approximately one fifth of the surface currently covered by permafrost. The equivalent figure for Alaska is 57 per cent. The length of the winter season and the snow coverage in the Arctic will continue to decrease and the glaciers in the area will probably lose between 10 and 30 per cent of their total mass. All this within this century and with grave consequences for the ecosystems, existing infrastructure and human living conditions.

New estimates also show that by 2100, the sea level will have risen by between 0.9 and 1.6 metres, which is approximately twice the increase predicted by the UN's panel on climate change, IPCC, in its 2007 report. This is largely due to the rapid melting of the Arctic icecap. Between 2003 and 2008, the melting of the Arctic icecap accounted for 40 per cent of the global rise in sea level.

"It is clear that great changes are at hand. It is all happening in the Arctic right now. And what is happening there affects us all," says Margareta Johansson.

The report "Impacts of climate change on snow, water, ice and permafrost in the Arctic" has been compiled by close to 200 polar researchers. It is the most comprehensive synthesis of knowledge about the Arctic that has been presented in the last six years. The work was organised by the Arctic Council's working group for environmental monitoring (the Arctic Monitoring and Assessment Programme) and will serve as the basis for the IPCC's fifth report, which is expected to be ready by 2014.

Besides Margareta Johansson, Torben Christensen from Lund University also took part in the work.

More information on the report and The Artic as a messenger for global processes - climate change and pollution conference in Copenhagen can be found at: http://amap.no/Conferences/Conf2011/