2 June 2016, The guardian, Spike in Alaska wildfires is worsening global warming, US says Report from US Geological Survey says northern wildfires must now be seen as significant driver of climate change, not just a side-effect. The devastating rise in Alaska’s wildfires is making global warming even worse than scientists expected, US government researchers said on Wednesday. The sharp spike in Alaska’s wildfires, where more than 5 million acres burned last year, are destroying a main buffer against climate change: the carbon-rich boreal forests, tundra and permafrost that have served as an enormous carbon sink. Northern wildfires must now be recognised as a significant driver of climate change – and not just a side-effect, according to the report from the US Geological Survey. “This is one of the surprises that we haven’t talked about much,” said Virginia Burkett, chief climate scientist at the USGS. “It has tremendous implications for the carbon that is locked up in Alaska soils and vegetation.” A record wildfire year – such as 2015 which was the worst in Alaska for a decade – had a measurable effect on the release of carbon dioxide and methane, which are the main drivers of climate change. “Our scientists found that the balance of carbon storage versus release in Alaska was strongly linked with wildfires,” Burkett said. “In years where there was high wildfire activity the net carbon balance declined dramatically, and then it would rebuild in the absence of fire.” Alaska is a far bigger storehouse for carbon than the lower 48 states, according to the USGS. The state’s boreal forests, peat-rich tundra, and permafrost hold about 53% of US carbon. Alaska accounts for about 18% of US land mass. Alaska currently absorbs about 3.7m tonnes of carbon a year, the USGS assessment found. But that vast storehouse of carbon has been breached by warming temperatures, thawing permafrost – and wildfire. Read More here
Tag Archives: Bushfire
10 May 2016, New York Times, Global Warming Cited as Wildfires Increase in Fragile Boreal Forest. Scientists say the near-destruction of Fort McMurray last week by a wildfire is the latest indication that the vital boreal forest is at risk from climate change. Scientists have been warning for decades that climate change is a threat to the immense tracts of forest that ring the Northern Hemisphere, with rising temperatures, drying trees and earlier melting of snow contributing to a growing number of wildfires. The near-destruction of a Canadian city last week by a fire that sent almost 90,000 people fleeing for their lives is grim proof that the threat to these vast stands of spruce and other resinous trees, collectively known as the boreal forest, is real. And scientists say a large-scale loss of the forest could have profound consequences for efforts to limit the damage from climate change. In retrospect, it is clear that Fort McMurray, in northern Alberta, was particularly vulnerable as one of the largest human outposts in the boreal forest. But the destruction of patches of this forest by fire, as well as invasions by insects surviving warmer winters, has occurred throughout the hemisphere. In Russia, about 70 million acres burned in 2012, new statistics suggest, much of that in isolated areas of Siberia. Alaska, home to most of the boreal forest in the United States, had its second-largest fire season on record in 2015, with 768 fires burning more than five million acres. Global warming is suspected as a prime culprit in the rise of these fires. The warming is hitting northern regions especially hard: Temperatures are climbing faster there than for the Earth as a whole, snow cover is melting prematurely, and forests are drying out earlier than in the past. The excess heat may even be causing an increase in lightning, which often sets off the most devastating wildfires. Read More here
1 April 2016, Climate News Network, New strategy devised to tackle wildfires. High-risk areas mapped and targeted in efforts by the US and Europe to reduce the risks of catastrophic economic and health damages caused by forest fires. Communities in both Europe and the US are preparing to fight fire not with fire, but with information. European researchers have just established a map of the regions most at riskfrom catastrophic wildfire. And in the US, where 2015 saw more fire damage than any other year on record, a new Wildland Fire Science Centre in Reno, Nevada, hopes to help federal, state and local agencies confront and better prepare for the hazards. The reasoning on both continents is the same. “In the regions we have identified as high risk, local authorities need to prioritise fire risk control and develop better forest fire risk management strategies,” says Heiko Balzter, director of the Centre for Landscape and Climate Research at the University of Leicester, UK. Read More here
23 February 2016, The Conversation, Aboriginal fire management – part of the solution to destructive bushfires. As destructive bushfires become more common there is increasing political discussion how we manage them sustainably. Inevitably these debates raise questions of the past ecological effects of Aboriginal fire usage. There are two well-known narratives about Aboriginal fire use. One, popularised by Tim Flannery, stresses the ecologically disruptive impact of Aboriginal fire use. This storyline argues that the megafauna extinctions that immediately followed human colonisation in the ice age resulted in a ramping up of fire activity. This then led to the spread of flammable vegetation which now fuels bushfires. Another, promoted by Bill Gammage, suggests that the biodiverse landscapes that were colonised by the British were the direct product of skilful and sustained fire usage. Such broad-brush accounts give the impression that the specific details of Aboriginal fire usage are well-known and can be generalised across the entire continent. Sadly this is not the case. So rapid was the socio-ecological disruption of southern Australia that researchers have had to rely on historical sources, such as colonial texts and images, and tree rings, pollen and charcoal in lake sediments, to piece together how Aboriginal people burned the land. Such records are open to interpretation and there remains vigorous debate about the degree to which Aboriginal people shaped landscapes. Piecing together the past There are only a handful of detailed observational studies of the ecology of Aboriginal fire usage, and all from northern Australia, so there is dispute whether their findings can be extrapolated in the south. These studies demonstrate skilful use of fire that created fine-grained burn patterns, designed to promote food resources. For instance, a prime motive for burning savannas is attracting kangaroos to nutrient-rich grass that sprouts after the fire. In the desert, Aboriginal patch burning increases the habitat for sand goannas. In sum, there is mounting evidence that sustained Aboriginal fire use shaped many Australian landscapes by sharpening vegetation boundaries, maintaining open vegetation, and creating habitat for game species. Read More here