By Rob Taylor
    Reuters

    Friday 19 January 2007

    They burn like fire hurricanes on fronts stretching sometimes thousands of kilometres and with a ferocity that explodes trees and makes them impossible to extinguish short of rain or divine intervention.

    Bushfires like those that had raged through Australia's southeast for two months and struck Europe, Canada and the western US in 2003 were a new type of "megafire" not seen until recently, a top Australian fire expert said today.

    "They basically burn until there is a substantial break in the weather, or they hit a coastline," Kevin O'Loughlin, chief executive of Australia's government-backed Bushfire Cooperative Research Centre, said.

    "These fires can't be controlled by any suppression resources that we have available anywhere in the world."

    Wildfires have struck five of Australia's six states since November, blackening more than 1.2 million hectares of bushland, killing two people and gutting dozens of homes.

    An army of 15,000 volunteers is being assisted by firefighters from Canada and New Zealand, with more teams from the US expected to arrive next week.

    Mr O'Loughlin said international experience pointed to megafires becoming usual in many parts of the world, driven in part by global warming and by laws protecting national parks, which provided a source of fuel to megafire fronts.

    Huge fires devastated large parts of Portugal, Spain and France in 2003, and also struck Canada and the US as well as Australia, which is the world's most fire-prone country.

    "Even in the US, which has quite substantial suppression resources - helicopters, the army, fleets of planes - they still cannot control them," Mr O'Loughlin said.

    Megafires are created when separate fires link and create one "super-front". Some of Australia's fires this summer have borders stretching thousands of kilometres, although authorities have been fortunate in that most have been in remote mountain ranges.

    The fires are so fierce they create their own weather and winds, sucking in air from all directions.

    "Once you get to a certain size the fire takes on a life of its own and, for example in Canberra in 2003, you got fire tornadoes," Mr O'Loughlin said, referring to blazes which swallowed entire suburbs in Australia's capital four years ago.

    To tackle megafires amid global warming, governments worldwide might have to consider unlocking protected parklands and rejecting environmentalist arguments against intentionally burning dry timber littering the forest floor, he said.

    Climate change was also playing a part, reducing seasonal rains in some areas and drying out forests.

    "The forests now form a major fire hazard. In the US they are starting to reintroduce fire to forested areas, but that is a very sensitive topic and you need to bring people along, especially parts of the conservation movement," Mr O'Loughlin said.

    Experts from Australia and around the world will gather in Canberra on February 27 to consider how to tackle megafires.

    "It's to do with land management, water resources, forestry resources, and it will require political decisions to be made," Mr O'Loughlin said.