The fierce bushfires that scorched Australia’s Victoria State released millions of tonnes of carbon dioxide, a leading scientist has warned.
Forest fires could become a growing source of carbon pollution as the planet warms, he told Reuters news agency.
Mark Adams of the University of Sydney said global warming could trigger a vicious cycle in which forests could stop becoming sinks of CO2, further accelerating the rise of the planet-warming gas in the atmosphere.
“With increasing concerns about rising CO2, rising temperatures and reduced rainfall in many of the forested areas, then we could well see much greater emissions from forest fires,” added Professor Adams, dean of the Faculty of Agriculture, Food and Natural Resources.
The Victoria fires, which killed more than 200 people, were the worst in the nation’s history and many were still burning weeks later.
“Scientists worldwide are worried about fires and forests.
“It doesn’t matter if it’s the Arctic tundra fires, or peat fires in Kalimantan or bushfires in Australia,” observed the Australian researcher, who has worked in collaboration with the Bushfire Co-operative Research Centre.
In a submission to the United Nations last year, the Australian government said wildfires in 2003 released 190 million tonnes of CO2-equivalent, roughly a third of the nation’s total greenhouse gas emissions for the year.
Such large, one-off releases of CO2 and other greenhouse gases such as methane, are not presently accounted for in Australia’s annual list of national greenhouse gas emissions.
If they were, the country would vastly exceed its emission limits under the Kyoto Protocol, the United Nations’ main weapon to fight climate change.
This is one reason, critics say, why Australia is calling for amendments to UN rules on land use change, so that only human activities that “can be practicably influenced” are included.
Professor Adams said the UN climate summit at the end of the year in Denmark should discuss the growing threat from forest fires and how to develop better legal frameworks to tackle the problem.
In a study of how much carbon Australia’s forests and soil can store, he estimated that fires in 2003, which ravaged the capital Canberra, and in 2006-07 released about 550 million tonnes of CO2.
The current fires had already burned hundreds of thousands of hectares, he said, in areas with total carbon content of 200 tonnes per hectare or more.
Australia, though, was not his only concern; annual fires in Indonesia also release vast amounts of CO2.
Huge fires in 1997 released up to 6 billion tonnes of CO2, covering South-East Asia in a thick haze and causing a spike in global levels of the gas.
Research on the forest and peat fires by a team of international scientists found the blazes released the equivalent of up 40% of global annual emissions from burning fossil fuels.
Professor Adams described the findings as a “wake-up call”.
“When you see the step-increases (of CO2) that they observed, we have to sit up and take notice, that fires are a major problem,” he said.
In the past, he explained, native forest carbon had been in rough equilibrium over millions of years with fires, with very small accretion of carbon over very long periods of time.
“But then if you add rapid climate change and much greater fire frequency, the equilibrium carbon content of the native forests, instead of going up, is going to go down.”
Filed under: carbon, climate change, deforestation, forest fires, sequestration Tagged: | australia fires, bush fires, carbon cycle, carbon sinks, carbon stores, climate change, climate deal, climatology, CO2, copenhagen, environment, global warming, greenhouse gases, kyoto, land use, rising temperatures, un, university of sydney, victoria, wildfires