Burning issues – Will a changing climate increase the incidence of wild fires?

Are wildfires going to be a common occurrence due to global warming and climate change? This is a subject discussed in a report presented this week at the 5th International Wildland Fire Conference in Sun City, South Africa. The report, entitled "Findings and Implications from a Coarse-Scale Global Assessment of Recent Selected Mega-Fires", examined recent fires in Australia, Botswana, Brazil, Indonesia, Israel, Greece, Russia, and the United States.

Coincidentally, the report was released just as fire-fighters were ending a week of hard work to tackle the recent wildfires that affected England’s forests leaving vast areas of burnt land. The large scale and intensity of these fires was due to the vegetation being dry after the hottest April on record. It is still not clear what started the fires, but it is quite possible that human carelessness is to blame; for example lit cigarette thrown out by passing drivers. Strong winds meant the fires swept across firebreaks, leaving a trail of devastation and causing families to be evacuated from homes near the forest in Berkshire, Lancashire, Yorkshire and parts of Wales, Northern Ireland and Scotland, The Telegraph online reported at the weekend.

Other recent examples of large wildfires include the 2009 Black Saturday blaze in Australia, which killed 173 people and record-setting wildfires in Russia last year, where 62 people were killed and around 2.3 million hectares burned as a result of over 32000 fires.

Nearly all of the mega-fires studied in the report were due to human interferences. Often fires are deliberately set in order to clear land for agricultural or development purposes. Drought was implicated in all but one of the mega-fires examined. Hot, dry and windy conditions accompanied all of the wildfires studied in the report. In tropical forests, mega-fires are mainly fuelled by dried-out woody debris left behind from logging and land clearing for plantations and crop production.

Although most mega-fires were found to be started by humans, they were likely exacerbated by the effects of climate change. Furthermore, whilst changing climatic conditions may be exacerbating the growing number of mega-fires around the world, these fires may also themselves be a contributing factor to global warming, said the FAO report. Therefore, we could be entering a vicious circle effect as well.

As wildfire risks intensify, the report suggests the importance of more balanced, more comprehensive wildfire protection approaches that better integrate fire-related considerations into natural resource management strategies at the landscape scale.

My search of the CABI Environmental Impact resource using the terms "wildfires" and "climate change" gave over 600 records, including 596 from the CAB Abstracts database.

Link to FAO press release. http://www.fao.org/news/story/en/item/74214/icode/

Link to FAO report. http://foris.fao.org/static/pdf/fm/5thIWFConference2011.pdf

Link to The Telegraph article.

Swimley Forest, UK, Image from Google Images.