This almost looks like a magic trick, but it shows what can happen with very deep-seated fires, such as peat. Smouldering underground with limited oxygen, the very hot material and gasses can transition into flaming combustion once introduced to an atmosphere with a higher concentration of oxygen.
“The scary thing is future climate change may … dry out peatlands. If peatlands become more vulnerable to fire worldwide, this will exacerbate climate change in an unending loop.” Guido R. van der Werf
Six researchers have written a paper about how climate change is expected to increase the number of peat fires worldwide. This is disturbing for a number of reasons, including the health effects of the additional smoke that humans must breathe, and the additional carbon in the atmosphere may “exacerbate climate change in an unending loop.”
The researchers — Merritt R. Turetsky, Brian Benscoter, Susan Page, Guillermo Rein, Guido R. van der Werf, and Adam Watts — all work for universities. Even though the funding was supplied by five government agencies, if you want to read their paper at Nature Geoscience it will cost you between $5 and $32. Open Access is apparently not a priority for the universities and government agencies that are responsible for this important taxpayer funded research. The agencies that funded the research, other than the universities that employ the scientists, are National Science Foundation (NSF), NASA, The European Research Council, the Natural Sciences and Engineering Research Council of Canada, and the Desert Research Institute’s Division of Atmospheric Sciences (the environmental research arm of the Nevada System of Higher Education).
Government agencies should not fund research unless there is a guarantee that the results will be immediately, freely, and easily available on the internet.
Below is an article about their findings, supplied by the Desert Research Institute, the environmental research arm of the Nevada System of Higher Education, the employer of Mr. Watts.
The natural disaster plays out like a movie script – ash falling from the sky, thick smoke shutting down airports and businesses across the globe, and uncontrollable fires burning for days and weeks. But this is not from a script; rather, it is a vivid description of a future climate change scenario in which the Earth’s peat-rich regions become more susceptible to drying and burning.
New research published this week in the journal Nature Geoscience, co-authored by Adam Watts, a fire ecologist at Nevada’s Desert Research Institute (DRI) and deputy director of DRI’s Climate, Ecosystems, Fire and Applications Program, outlines the threat of drying peatlands (also known as mires) across the globe and their increased vulnerability to fire and carbon loss.
Peatlands – which make up around three-percent of the Earth’s land surface and store approximately 25-percent of the world’s soil carbon – are deposits of plant material and organic matter mixed with soil that is too wet to support high levels of decomposition. Peatlands are found on all seven continents.
Already the largest fires on Earth in terms of their carbon footprint, these smoldering fires burn through thick layers of peat, built up over thousands of years, which blanket the ground in ecosystems ranging from the tropics to the arctic.
“When people picture a forest fire, they probably think of flames licking up into tree tops, and animals trying to escape,” said the study’s lead author Merritt Turetsky, a professor of Integrative Biology at University of Guelph in Ontario, Canada. “But peat fires tend to be creeping ground fires. They can burn for days and weeks, even under relatively wet conditions. They lack the drama of flames, but they produce a lot of smoke.”
That smoke contains large amounts of carbon and makes peat fires dangerous to human health. It can worsen air quality and even trigger asthma and other respiratory problems.
“In addition to the amount of carbon released, the types of emissions also can make smoldering fires of greater concern than fires where most of the combustion takes place in flames,” said Watts, who is studying the emissions from burning peat and many other types of organic fuels with his DRI colleagues to determine their potential effects in the atmosphere and on our global climate.
“Peat fires are an example of wildfires having effects far beyond the areas where they occur, and these effects can last for a very long time,” he added.
Turetsky and former University of Guelph post-doctoral researcher Brian Benscoter teamed up with temperate and tropical fire scientists to summarize what is known about peat fires, from massive lightning-ignited fires that burn large areas of the boreal region to tropical fires often triggered by human activity.
“The tropical peatlands in Southeast Asia are a clear demonstration of how human activity can alter the natural relationships between ecosystems and fire,” explained Susan Page, a University of Leicester professor and co-author on the study. “Tropical peatlands are highly resistant to natural fires, but in recent decades, humans have drained peatlands for plantation agriculture. People cause the deep layers of peat to dry out, and also greatly increase the number of fire ignitions. It’s a double threat.”
This causes a host of problems, including health issues, airport and school closures, and political tensions.
The paper concludes that almost all peat-rich regions will become more susceptible to drying and burning with a changing climate. The authors also note that the ecology of peat fires and the role of peat fires in long-term Earth system processes need to be explored more thoroughly in future research.
“Thanks to satellite data, we are fully aware of the vast scale of burning in drained peatlands, mostly in Indonesia,” said co-author Guido van der Werf, a professor at Amsterdam’s VU University. “The scary thing,” Werf added,” is future climate change may actually do the same thing: dry out peatlands. If peatlands become more vulnerable to fire worldwide, this will exacerbate climate change in an unending loop.”
This research was supported by the National Science Foundation (NSF), NASA, The European Research Council, the Natural Sciences and Engineering Research Council of Canada, and the Desert Research Institute’s Division of Atmospheric Sciences.
Peat fires can burn up to 15 feet deep and are extremely difficult to extinguish. Russia, which has been plagued by peat fires this summer, constructed a 30-mile-long water pipeline from the Oka River to an area with peat fires east of Moscow.
The excerpt below is from a New York times article and is a quote from Guillermo Rein, an expert on smoldering subterranean fires and an assistant professor at the University of Edinburgh in Scotland.
Smoldering fires, the slow, low-temperature, flameless form of combustion, are an important phenomena in the Earth system, and the most persistent type of combustion. The most important fuels involved in smoldering fires are coal and peat. Once ignited, these fires are particularly difficult to extinguish despite extensive rains, weather changes or firefighting attempts, and can persist for long periods of time (months, years), spreading deep (5 meters) and over extensive areas of forest subsurface. Indeed, smoldering fires are the longest continuously burning fires on Earth. The Burning Mountain, a coal deposit in New South Wales, Australia, has been smoldering since 4,000 B.C.
The characteristic temperature, spread rate and heat released during smoldering are low compared to flaming fires. Smoldering peat fires creep at a speed of 1 meter per day. Whereas flaming fires result in superficial heating of the soil, smoldering leads to sterilization and loss of mass above 90 percent (a layer of 5 meters is reduced to 30 centimeters). Moreover, these fires are difficult to detect with current remote sensing methods because the chemistry is significantly different, their thermal signature is much smaller, and the smoke plume is much less buoyant than the emissions from flaming fires.
Smoldering fires can be ignited by natural causes such as wildfires, lightning strikes, self-heating or anthropogenic factors, e.g., slash and burn, arson, mining activities or waste incineration. The most typical scenario for peat fires is when a fast flaming wildfire sweeps over a region burning the surface vegetation and igniting the peat if this is dry enough. The peat then smolders for a much longer time. This is what happens in Indonesia and probably what has occurred in Russia this summer.
Water content of the peat governs smoldering ignition. The depth and the area affected in case of fire are also be dictated by the water content of the peat layers. The maximum water content for boreal peat to ignite has been measured to be 55 percent by weight. Any water content bellow this means the peat can smolder.
Wildfires in Russia, mostly from burning peat-bogs, are creating the worst smog Moscow has seen since 2002 and is exposing citizens to pollution that is 10 times above safe levels. Residents are inhaling the equivalent of 40 to 50 cigarettes every few hours.
Some reports say the peat-bogs spontaneously ignited. Here is an excerpt from the Epoch Times:
Moscow city center was enveloped by thick smoke on Wednesday coming from wildfires outside the Russian capital. The fires were sparked by the hot weather and drought that the country has been suffering this month.
Emergency officials say that peat-bog fires that can spontaneously burst into flames, are to blame for a large part of the natural disaster.
Russia’s emergency ministry has so far recorded about 50 flashpoints of peat-bog fires across the country, 43 of which are in the Moscow region.
The Russian meteorological office reports that the central region of the country, including Moscow, is currently most susceptible to fires.
On Tuesday, in a small village of Vladimirskaya, neighboring Moscow, wildfires destroyed about 20 houses. There were no reported deaths or injures.
Forty-two fires broke out overnight in peat bogs drained for agriculture during the Soviet era, including 39 in central Russia, according to the Emergency Situations Ministry. All but two of the fires were extinguished.
HERE is a link to a satellite photo of the smoke near Moscow.