Slashdot Mirror


Is Climate Change Affecting Bushfires?

TapeCutter writes "After the devastating firestorm in Australia, there has been a lot of speculation in the press about the role of climate change. For the 'pro' argument the BBC article points to research by the CSIRO. For the 'con' argument they quote David Packham of Monash university, who is not alone in thinking '...excluding prescribed burning and fuel management has led to the highest fuel concentrations we have ever had...' However, the DSE's 2008 annual report states; '[The DSE] achieved a planned burning program of more than 156,000 hectares, the best result for more than a decade. The planned burning of forest undergrowth is by far the most powerful management tool available...' I drove through Kilmore on the evening of the firestorm, and in my 50 years of living with fire I have never seen a smoke plume anything like it. It was reported to be 15 km high and creating its own lightning. There were also reports of car windscreens and engine blocks melting. So what was it that made such an unusual firestorm possible, and will it happen again?"

4 of 397 comments (clear)

  1. Why don't the Austrailians build differently? by Anonymous Coward · · Score: 5, Insightful

    Some years ago, Fine Homebuilding did an article about houses that did and did not survive wildfires in California. The houses that survived had certain characteristics. They were clad with non-burning material like stucco. They had metal or tile roofs. They didn't catch heat under the eaves. They didn't have trees near the house. The plantings they did have mattered. There was one kind of ground cover that was full of water and that would burst if heated, releasing the water and cooling the fire.

    The Australian houses I have seen (in pictures, I haven't been there) had almost none of the characteristics of the houses that survived the California fires. So, my question is; if you live in a country that has bush fires, why don't you build your houses to accommodate that fact?

  2. Goverment failed to back-burn, that is the story by Anonymous Coward · · Score: 5, Insightful

    David Packham is our foremost expert in this area, he "wrote the book".

    It is clear that when you let 35-50 tonnes of fuel build up per hectare by not backburning then you will get these sized fires.

    We have had similar fires in the 1850s, 1870s, 1930s, 1980s. The common factor is the amount of fuel ready to be burnt.

    Shouldn't Climate Change have actually reduced fuel load by killing the trees?

    It has a lot to do with the fact that the Government departments failed to conduct the necessary backburning.

    There will always be arsonists, lightning strikes and stray cigarettes. We can't stop ignition. We CAN reduce the amount of fuel available to a bushfire. Climate change has nothing to do with proper back burning.

  3. Re:CO2 causes Global Warming? by vadim_t · · Score: 5, Insightful

    There are different ways of acting.

    Stopping dumping tons of crap into the atmosphere is unlikely to make things worse. Now trying to fix things by releasing some other chemical to try to balance the problem could backfire.

    The first is like "Shouldn't we understand the complete ecosystem of the lake before we stop using it as a garbage dump?". It's generally unnecessary to wait to have a 100% complete understanding. Maybe the fish are dying for some other reason, but stopping dumping junk is unlikely to make things get any worse.

    The second is more like "The lake seems too acid, maybe we should compensate by dumping several tons of base to neutralize". Now this kind of solution will require a complete understanding, lest it turns out that wasn't the problem, and things become even worse than before.

  4. Re:CO2 causes Global Warming? by JWSmythe · · Score: 5, Insightful

      I was working under the assumption that the GP was indicating that we were suggested to step back into the stone age. That would be the entire population of earth, without modern technology to assist us. Really, I think the farthest back we would go would be to agrarian society, but that would have significant drawbacks.

        Say something cataclysmic happened tonight, and in the morning there was no power grid, no city water, no supply chains for food, fuel, etc. I'll focus on only the United States, because I am more familiar with it, and finding numbers relating to it.

        According to the 2000 US census, just about 226 million people lived in 3,629 population centers that could be considered "Urban". That's just over 79% of the US population.

        Assuming these people had exactly what they started out with before they went to bed, they typically would have 0 to 14 days of food supply on hand, and assuming the use of any water supplies available (i.e., toilet tank water, bottled water, etc), they may have a 3 to 4 day supply of water. Right now, if there is sufficient snow on the ground, some people may be smart and gather all the fresh fallen snow that they can. Virtually no one has any provisions for collecting rain water for drinking or cooking use.

        In up to 11 days, people will begin dying of dehydration. In up to 28 days, mass starvation would take effect. Sometime between day 1 and day 10, people will begin using force to horde supplies from weaker people.

        Some people will realize the futility of remaining in an urban area, and attempt to leave. In a best case scenario, starting with a fully fueled vehicle, and ideal cruising conditions, passenger vehicles can travel 400 miles. That's a best case. In reality, it won't be just one person saying "we have to get out of here", it will be hundreds of thousands. One accident, vehicle running out of fuel, or mechanical failure, and all vehicles behind them will come to a stop.

        The 21% living in "Rural" areas may have a better chance. If (IF) they are lucky, they have a fresh water supply that does not depend on electricity. Most rural homes I've seen are supplied with water from electric pumps. If they are lucky, they have a good on-hand food supply. If they are lucky, they already have a food crop that can be harvested on a regular basis.

        In reality, the numbers dwindle. Less than 1% of the 79% of the urbanites will be lucky enough to get to somewhere survivable, but they won't be alone. Less than 25% of the 21% rural dwellers will have the necessities on hand for continued survival without our modern infrastructures. i.e., how do you plow a field without a tractor (no fuel). How do you trade bare essentials with your neighbors who you can't reach without a car (no fuel).

        But, if the 285 million people in the United States did manage to disperse from the urban centers, to areas that could sustain them temporary for food, water, and shelter, and they managed to have or improvise hand tools to cut down trees, make fire for warmth and cooking, it would be absolutely disastrous for the environment.

        This is an easy game to play. Go into your garage and shut off the main breaker (or pull the main fuse in older homes). Shut off the water and gas mains. Take all the money out of your wallet, and your credit cards, and stick them in an envelope somewhere safe that you won't touch them. Now, survive for 6 months.

        In reality, if we stepped back to the "stone age" tonight, only small pockets of humanity would survive, and they would be the rural dwellers who live in fresh water rivers, have farms, and can live off the land. Everyone else will die.

    --
    Serious? Seriousness is well above my pay grade.