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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?"
More fundamentally, no one drought can be directly attributed to global warming, just as the current cold winter in NA can be considered as casting doubt on global warming.
Over time, global warming may make droughts such as the one that exacerbated the current AU fire situation more common. During the change, the vegetation left over from the wetter period before global warming will result in some spectacular fires, but it will only be in hindsight that we can say fires were a result of the change.
Its a good question. About a week ago there was an article in the paper here in Melbourne about a family who survived the fires in a concrete house. Building standards are going to change before new houses are built so I expect the situation to improve.
Some of the houses in the affected areas were as much as 100 years old. They were built when timber was the only material available. Later houses tended to be built the same way either because of tradition, or people wanting to build houses which fitted in with the historic designs.
I work with a guy who has a two story oiled timber house. On the day of the fire he was away from home with his family. When he finally got back a couple of days later he was surprised to find it still there. Another person I work with lost his home (and old farm house) in the fire and barely escaped. They actually drove one way into the fire, turned around and took the last clear road out of the area.
As for vegetation around houses home owners have been blaming local council regulations which prevent them from cutting down trees. One family were fined for removing a tree and later credited that act with saving their house.
http://michaelsmith.id.au
Yes, the building code could certainly do with an upgrade. When I was growing up many people had small fire bunkers dug into the ground and every local fire-brigade had a air-raid style siren. Neither are common today.
"As for vegetation around houses home owners have been blaming local council regulations which prevent them from cutting down trees. One family were fined for removing a tree and later credited that act with saving their house."
You may be interested in the councils side of that story, the minutes can be found here (pdf warning). I don't know what happend to the four acres of trees Mr Shehan cut down but from my days working on an old growth sawmill a back of the envelope calculation says that many trees would have yeilded ~5000 tons of processed timber and several thousand tons of woodchips.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
Climate change isn't the theory. It is the effect. The theory is that greenhouse gases raise the temperature of the atmosphere of a planet. This has been well tested with small scale experiments and large scale observations (such as observing the atmospheric composition and temperatures of Mars and Venus). There are a lot of details that go into climate change, but the general idea is very common sense:
Step 1: Shine some light in the visible spectrum on an object through a gas that doesn't absorb a huge amount of energy at most of those wavelengths (for example, from any random object that you might see that has a 5780 K blackbody temperature).
Step 2: Choose an appropriate gas (like CO2 or methane) that will absorb a lot of energy from the blackbody emissions of that object (Stefan's Law).
Step 3: Watch the temperature of that gas rise.
Do you get the gist? It isn't rocket science. If you add a shitload of CO2 to the atmosphere, the temperature of the surface of the planet is going to rise.
Suddenly, the hairy finger of a familiar monkey tapped me on the shoulder. It was time.--G. T.
The real issue is that there is currently no unambiguous method of measuring the global temperature
No, the real problem is that "global temperature" isn't a meaningful thermodynamic quantity. Global atmospheric heat content is, but no one has a clue what that is because we need to know both temperature and humidity (ie, both wet and dry bulb temperatures) to determine it.
However, global ocean heat content appears to be measurable, and appears to be rising.
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