Friday, 6 May 2016

Peat fires in the tundra and other articles related to the Alberta wildfires

This is a collection of articles that provides some context to the wildfires in Alberta – something sorely missing from the media discussion that fails to even tell us that Fort McMurray is situated in the tar sands area of Alberta, that this is conencted to unprecedented heat caused by disruption of the jetstream, a major symptom of abrupt climate change.


Join the dots.

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According to the authors, their observations of carbon loss from the Anaktuvuk River fire support the idea that tundra fires have the potential to release large amounts of carbon and decrease landscape carbon stocks, having an immediate impact on atmospheric carbon and climate.”


Largest recorded tundra fire yields scientific surprises


This NASA MODSIS image of the North Slope of the Brooks Range in Alaska shows the Anaktuvuk River fire scar in the lower right quarter of the image. Credit: NASA/GSFC, MODIS Rapid Response

27 July, 2011

In 2007 the largest recorded tundra fire in the circumpolar arctic released approximately as much carbon into the atmosphere as the tundra has stored in the previous 50 years, say scientists in the July 28 issue of the journal Nature. The study of the Anaktuvuk River fire on Alaska's North Slope revealed how rapidly a single tundra fire can offset or reverse a half-century worth of soil-stored carbon.

Tundra soils store huge amounts of carbon hundreds to thousands of years old. Intact, the layers of organic soil insulate the permanently frozen ground, called permafrost, below.

"Fire has been largely absent from tundra for the past 11,000 or so years, but the frequency of tundra fires is increasing, probably as a response to climate warming," said co-author Syndonia "Donie" Bret-Harte, an ecosystem ecologist at the University of Alaska Fairbanks Institute of Arctic Biology.

The Anaktuvuk River fire burned 1,039 square kilometers (401 square miles), an area roughly the size of Cape Cod and visible from space, and released more than 2.1 teragrams (2.3 million tons) of carbon into the atmosphere. Radiocarbon dating of the soils revealed the maximum age of the soil carbon emitted from the fire was 50 years.

"The amount of carbon released into the atmosphere from this fire is equivalent to the amount of carbon stored by the global tundra biome," said lead author Michelle Mack, a biologist from the University of Florida. "This was a boreal forest-sized fire."

Little is known about the effects of fire on carbon storage and cycling in tundra ecosystems. Cool, wet soils underlain by permafrost are thought to restrict fires to aboveground plants and ground-level plant litter leaving the carbon stored in soils relatively intact. As arctic summers get warmer and dryer, so too do the soils, which are highly flammable and able to burn more deeply when dry.

"If the frequency of these fires remains at long intervals, 80 to 150 years, then the tundra has time to recover," Bret-Hart said. "If these fires occur more frequently, say every 10 years or so, then the landscape cannot recover."

The Anaktuvuk River fire was started by a lightning strike in July 2007. "Normally we would expect the fire to go out in the moist soil, but this summer was so dry that the fire didn't go out and strong winds in September caused it to burn a very large area," said Bret-Harte, who noted that 40 percent of the fire was classified as a severe burn – high for a tundra fire. The fire was visible 24 kilometers south at the IAB Toolik Field Station, where the scientists were working, as a wall of smoke on the horizon.

In addition to the direct release of carbon into the atmosphere, tundra fires are important because of the potential feedbacks to global climate change. "These fires could be a radical and very rapid positive feedback to atmospheric carbon dioxide," said Mack.

Fire removes organic material that insulates permafrost from warm summer temperatures. Insufficient insulation can lead to thawing permafrost, destabilization of the ground surface and exposure of deep soil carbon to decomposition and release into the atmosphere – ultimately amplifying high-latitude warming.

According to the authors, their observations of carbon loss from the Anaktuvuk River fire support the idea that tundra fires have the potential to release large amounts of carbon and decrease landscape carbon stocks, having an immediate impact on atmospheric carbon and climate.


Provided by: University of Alaska Fairbanks




Greenpeace warns fires raging across forest and peatlands will match the worst year ever and exceed the total annual carbon output of the UK

Fires raging across the forests and peatlands of Indonesia are on track to pump out more carbon emissions than the UK’s entire annual output, Greenpeace has warned.

As well as fuelling global warming, the thick smoke choking cities in the region is likely to cause the premature deaths of more than 100,000 people in the region and is also destroying vital habitats for endangered orangutans and clouded leopards.

New drone video footage from Greenpeace from around the Gunung Palung national park in Kalimantan shows the peat fires smouldering underground, as well as flames burning down trees, and the thick haze they produce.

There have been almost 10,000 fires in the last month across Kalimantan (Indonesian Borneo) and Sumatra, with the drifting smoke also provoking protests from neighbouring Malaysia, Singapore and Thailand......

The record forest and peat fires of 1997 produced huge carbon emissions, estimated by scientists at between 0.81 and 2.57 gigatonnes (Gt), equivalent to 13-40% of the entire world’s annual fossil fuel emissions. It lead to the biggest annual jump in CO2 ever recorded. By comparison, the UK’s carbon emissions for the whole of 2014 were 0.52Gt.

The health impact of the forest and peat fires is also expected to be large, with the resulting premature deaths across south-east Asia estimated at 110,000 deaths in an average year. More than 75,000 people are already suffering from upper respiratory infections as a result of the haze, according to media reports.


Indonesia's peat fires make it the 4th-largest carbon emitter in the world


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"The McMurray Formation is a stratigraphic unit of Early Cretaceous age (late Barremian to Aptian stage) of the Western Canada Sedimentary Basin in northeastern Alberta.[3] It takes the name from Fort McMurray, and was first described in the outcrops exposed along the banks of the Athabasca River, 5 KILOMETERS (3.1 mi) north of Fort McMurray, by F.H. McLearn in 1917.[4] It is a well-studied example of fluvial to estuarine sedimentation, and it is economically important because it hosts most of the vast bitumen resources of the Athabasca Oil Sands region."





Danger map shows 'extreme' risk of fires in both provinces


As tens of thousands of residents flee from Fort McMurray, Alta., the threat of more fires continues to loom across Alberta and Saskatchewan.

On May 4, Natural Resources Canada indicated that the risk of fire is "extreme" in the two provinces.

A map the federal department produced for Wednesday shows a huge red zone over most of the region.

The Canadian Wildland Fire Information System is a computer-based system that monitors fire danger conditions across Canada.

The system creates a fire danger map based on daily weather conditions such as temperature and humidity.

It also takes into consideration factors like how easy it is to ignite vegetation, how difficult a fire may be to control, and how much damage a fire can do.




There appears to be little relief on the way to help with this year's uncharacteristically early start to British Columbia's fire season. BC Wildfire Service spokesman Kevin Skrepnek says cooler temperatures forecast for the coming days are unlikely to bring much rain and that worsening winds will likely only fan the flames.

British Columbia has turned down a request for help from Alberta to send firefighters to help battle the Fort McMurray blaze, as the province struggles with an early start to this year’s wildfire season.

Ryan Turcot, an information officer with the B.C. Wildfire Service, said Alberta made a request for help Tuesday through the national Canadian Interagency Forest Fire Centre. Requests go to all provinces and territories, so that those jurisdictions experiencing lower levels of activity can lend resources if available.

But B.C. is currently experiencing high levels of fire activity, especially in the Peace River Region, where more than 50 fires are burning and five evacuation alerts are in place. “Our personnel are currently fully engaged across the province,” said Turcot, in an email Wednesday morning.

Given the current level of fire activity in B.C, and the need to maintain necessary resources here, B.C. was unable to lend crews at this time. Future requests will be considered,” he said.





Smouldering peat fires already are the largest fires on Earth in terms of their carbon footprint,”explained mega-fire expert Prof. Guillermo Rein last week.

He is coauthor of a new study called “Global vulnerability of peatlands to fire and carbon loss,” which warns that massive, difficult-to-stop peatland fires are likely to become even larger in the future, as human activity keeps drying out the formerly wet peatlands.

Since a key reason many peatlands will become drier is global warming, and since peatland fires can release staggering amounts of carbon dioxide, this process is a vicious circle, a dangerous amplifying carbon cycle feedback.

From Indonesia to Botswana, from Scotland to North Carolina, peat mega-fires burn for months, destroy habitat, clog the air with haze, and self-accelerate climate change impacts.


Smouldering combustion is the slow, low temperature, flameless burning of porous fuels. It is especially common in wildland fuels which are thermally thick and form a char on heating. In the natural environment, smouldering fires burn two types of biomass: thick fuels like tree branches or logs, and organic soils like the duff layer or peat. These are characterized by having a significantly greater thermal time compared to fine fuels like foliage. The persistent smouldering of thick fuels is typically observed for a few days after a flaming wildfire has passed, and it is often referred to as residual combustion. This can make residual smouldering be responsible for the majority of the biomass burned during a wildfires.


PEATLANDS UNDER FIRE!

by Simon van Bellen ·

21 February, 2014

Can pristine, undrained bogs burn? Looking at the soggy surface conditions of most northern peatlands, it may be hard to believe that, even in a natural state, they can actually burn. Perhaps it is even more surprising to learn that the ones that can burn most frequently and severely are located in the colder regions of the global peatland distribution

The shadow of a past burn.

Simon examining a core in Quebec.

The peatlands of North America form a major part of the global peatland area, comprising about a third of the global peatland carbon pool. Many North American peatlands are located in boreal forests, where coniferous trees dominate the landscape. Since the onset of the Holocene, these peatlands have developed over millennia under continental climate conditions: relatively warm summers and cold, harsh winters with low precipitation. As a result of these extreme climate conditions, peat accumulation is limited to a growing season of only a few months and in the northern parts, patches of permafrost may occur in the form of peat palsas. In the coniferous forests surrounding the boreal peatlands, fires are frequent and intense and, more often than not, ignited by lightning. The occurrence of fires may be explained by the dry, warm summers, but also because of specific tree adaptation: jack pine (Pinus banksiana) and to a lesser extent black spruce (Picea mariana) need the intense heat for seed release and regeneration.

Helicopters are the only way to reach these remote bogs.
Evidence of an old burn at the bog edge.

The Canadian boreal peatland zone runs from eastern to western Canada. Going westward, climate becomes generally drier and the peatland vegetation cover changes from open Sphagnum bogs with shrubby hummocks and wet hollows in Quebec, to spruce-covered bogs in northern Alberta. Although forest fires are frequent in the entire Canadian boreal zone, peatlands are affected more frequently in western Canada because of the differences in vegetation cover. In the western part, peatlands have burned as frequently as the neighbouring uplands during the last couple of decades.


Fires directly release carbon to the atmosphere by combustion, but they also influence the functioning of the ecosystem in the long term. Fire and charcoal production alter the soil microclimate and microbial populations (e.g. testate amoebae) and therefore respiration dynamics. As fires may burn live vegetation and/or litter as well as peat, thecarbon balance of the peatlands is negatively influenced by recurrent fires. About 3 kg of carbon per metre squared can be released from a peat bog per fire in western Canada, which means that under the current climate conditions these bogs are only small net sinks of carbon. With ongoing climate change and more peat being burned, these bogs may even become net sources in the near future.
The situation is somewhat different in eastern Canada. During my Ph.D. research atUniversité du Québec à Montréal, I analysed peat cores from three open bogs from the Eastmain region in the heart of the spruce-dominated boreal forest, searching for evidence of peat burning and possible effects of varying fire regimes on peat carbon sequestration during the Holocene. In short, peat burns here too. However, peat fires are much less frequent than in western Canada and do not seem to affect the deeper peat. Therefore, fire has been a minor factor in the development of these peatlands, especially when compared to other external variables, of which Neoglacial cooling may have been the most important one.

A spectacular aerial view across the bogs in Quebec.

Charcoal from past burns in the peatland record.

A view across the bog in Quebec


Burning patterns can be highly variable at the ecosystem scale as well. In sites with micro-topographical features, hollows generally lose more organic matter by combustion than hummocks. The explanation for this lies in the nature of the hollow vegetation. During dry periods, hollows dry out much more rapidly than hummocks, because of the ‘loose’ nature of the Sphagnum species found here and their low potential for water retention, while the dense Sphagnum cover of hummocks retains humidity more effectively. Therefore, in these peatlands, hollows tend to burn more deeply.

Looking at the complex spatial and temporal patterns of peat fire occurrence, it may seem difficult to forecast peat fire regimes with ongoing climate change. In general, larger areas of forest will be affected and fire occurrence and fire season length are anticipated to increase for most of the Canadian boreal regions. One could argue that if forest fires become more frequent, peatlands too may burn more often. However, the sensitivity of peatlands to burning may not depend on the same meteorological variables that determine the sensitivity of forest stands. Alternatively perhaps, peatland vegetation, rather than weather, may be a critical factor. Either way, the fire regimes of boreal peatland regions are likely to become an increasingly important factor in the estimation of future carbon fluxes from natural sources.

Further reading:

de Groot, W.J., Flannigan, M.D., Cantin, A.S. (2013) Climate change impacts on future boreal fire regimes. Forest Ecology and Management 294: 35-44.

Turetsky, M., Wieder, K., Halsey, L., Vitt, D. (2002) Current disturbance and the diminishing peatland carbon sink. Geophysical Research Letters 29. doi:10.1029/2001GL014000.

Yu, Z. (2012) Northern peatland carbon stocks and dynamics: a review. Biogeosciences Discussions 9: 5073–5107

The worst U.S. mine fire, in Centralia, Pennsylvania, passed its 50-year mark last year. As coal-powered development spreads globally, so does the risk of underground fire.


The Centralia blaze, still burning more than 50 years after it began, ranks as the worst mine fire in the United States. But it is by no means the only one. More than 200 underground and surface coal fires are burning in 14 states, according to the U.S. Department of Interior's Office of Surface Mining Reclamation and Enforcement.

And with worldwide demand for coal surging, especially in industrializing nations such as India and China, mine fires have emerged as a global environmental and public health threat. Thousands of coal fires rage on every continent but Antarctica, endangering nearby communities. The blazes spew toxic substances such as benzene, hydrogen sulfide, mercury, and arsenic, as well as greenhouse gases like methane and carbon dioxide.

Final word from Sam Carana - 

Wildfires in the North threaten to cause large emissions of greenhouse gases and soot, which can settle on snow and ice in the Arctic and the Himalayan Plateau, with the resulting albedo changes causing a lot more sunlight to be absorbed, instead of reflected as was the case earlier. 

This in turn adds to the problem. 

Additionally, rising temperatures in the Arctic threaten to cause release of huge amounts of methane from sediments below the Arctic Ocean. 

This situation threatens to escalate into runway global warming in a matter of years
--SAM CARANA

The Threat of Wildfires in the North






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