Wall St was down 94 overnight, its biggest fall in a month, while the local market is down 66.
Once-in-a-century floods, drought and fire. Again.
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The NSW coast is burning in winter. Is the end nigh? No. It’s happened before. Australia has about 50,000 bushfires a year. Very few are killers. The best predictor of a bad bushfire year is drought. One wet winter won’t end this severe drought, but it will help. It’s been very wet in WA, good in SA and western Victoria, but not so wet around Melbourne. All eyes are on the spring rains, which have failed abysmally in recent years. Runoff is still pathetic in many regions. Queensland is laughing, but southern dams are years away from filling. But maybe the southern drought is permanent. Reading the Sunday Age in a Sunday daze, my gob was smacked by the following revelation: “Scientists studying Victoria’s crippling drought have, for the first time, proved the link between rising levels of greenhouse gases and the state’s dramatic decline in rainfall.” So said Melissa Fyffe in The Sunday Age on August 30. The “proof” is that climate modelling shows that the continental high-pressure systems that have blocked the wet westerly fronts for the past 13 years are intensifying. Rain fronts are thus forced south, missing the Australian coast. This happens in every drought, of course, but models suggest that anthropogenic greenhouse gases are the cause, therefore the change is permanent. Fyffe’s adamantine conclusion is not supported by the very Bureau of Meteorology source she quotes. He says “it’s reasonable” to believe that anthropogenic global warming is causing most of the problem. Hardly proof. Fyffe then retreats to “not all experts agree”, quoting one who rejects the argument. Scientists cringe at the epidemic of tabloid climatic hyperbole. The Queensland and NSW north coasts were deluged several times earlier this year. One priceless report told us it was “the third time in six months the region had experienced once-in-a-hundred-year floods”. With a welcome touch of satire, a smirking ABC Landline reporter said another district had its “second once-in-a-century flood in a few weeks”. The great drama of our time is climate change. It is bedevilled by three confusions: weather versus climate, local versus region versus global, and short memories. Climate change deniers in WA, SA and Victoria are chortling. It’s been a wet winter. In Tasmania, they’re manic. The state’s been swamped. Record rainfall in some places. Those puny westerly fronts have smashed the “AGW intensified continental high-pressure thugs. Alas, one swallow doesn’t make a pub crawl. Cherry-picking extreme weather events weakens your case. Both sides do it shamelessly. Australia is a continent. Recorded history is very short in climatic terms. Long droughts are normal. We just don’t know the deeper rhythms of the country, if there are any. Local records are broken all the time, somewhere. Different regions suffer drought or flood or fire simultaneously. The Dorothea Mackellar syndrome. Just like now. Tasmania floods while NSW burns. Unprecedented? No. Neither was Black Saturday. People forget. Officials feign amnesia. Why are there no fire historians and journalists? Don’t answer that. Just listen to the trams. Climate science is in its infancy and may never grow up. We have little idea what drives climate variability, apart from vague awareness of oceanic temperatures. Regional variations are huge and opaque. We don’t know how the 0.4 degrees of global warming since 1970 is affecting continental, let alone regional climate. Global warming has levelled off in the past decade, fuelling increasingly shrill polemic from AGW deniers and believers. But whether the global temperature rises or falls in future tells us little about regional Australian climates in the medium term. Therefore long-term bushfire prediction remains guesswork. Just look at official long-term weather predictions. The current spring forecast for most of the country is numbing: “the chance of a wetter-than-average season is between 40% and 50%. In other words the chances of above-normal falls are about the same as the chances of below normal.” For most of the SW the odds are a bit higher and for the SE a tad lower. But last April and June the bureau was predicting lower rainfall in Tasmania, SA and Western Victoria. They were wrong. Well, are we going to burn again this summer? The drought continues. A dry spring and hot summer will produce severe bushfire risk. Last summer’s rainfall map is salutary. Great rain in the north, mostly average elsewhere. But look at the hills north and east of Melbourne… |
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6 Comments
I’m sorry, what was the point of this article? Is the author a AGW “denier” or “believer”? I can’t really tell.
I was amused having given us the facts that “climate science is in its infancy and may never grow up” and that the BOM was “wrong” in their forecast of winter’s rainfall, the author goes on to make his own at the end.
No I’m not in the forecasting business Davo- my point was that the drought hasn’t broken (except in Taz) so a dry spring and hot summer will recreate bad bushfire conditions in the south.
And the point about AGW is that no one knows how it has affected/will affect regional weather or climate. Which doesn’t stop it being dragged into debate after every bushfire, windstorm or “rain event”.
Reading between the line I would say he’s a denier and that he works by belittleing anybody else with an opinion on the subject.
Dr Timbal of the Met did say that it is reasonable to think that anthropogenic warming is causing a lot of the drought and then he went on to quantify this with an estimate of 80% contribution. The reporter may have used the word proof, but reporters aren’t scientists. All science is based on the idea that theories can’t be proven only disproven. This doesn’t mean that theores aren’t useful, because they can’t be proven, because as models of the physical world they can still be used to predict the future within prescribed limits.
Mellissa Fyfe did not quote a contrary view of an EXPERT in this particular field of climate research. She quoted the CEO of the Murry Darling Basin, Rob Freeman, a professional public service manager, not a climate scientist. He used weasel words to put a corporate spin on the issue, but basically agreed with Timbal. I don’t think he was even responding directly to the research. What Freeman was quoted as saying is:
“Some commentators (not scientists) say this is the new future. I think that is an extreme position and probably a position that’s not helpful to take,” he said, expressing confidence that wetter times would return.”
He did not say that things would return to normal, he simply said it would get wetter. I would have asked him how wet? And to what level of confidence. He may have provided facts to back his words. If he did, they were not reported.
The idea that we have no clue as to the severity of drought in Australia is rubbish.
Significant work has been done by a number of scientists in this area. Of particular relevence to the climate in South Eastern Australia is the work of Caroline Ummenhofer, of the Climate Change Research Centre (CCRC) regarding the effects of the Indian Ocean Dipole on South East Australian rain fall. She demonstrates clearly using rainfall and the Palmer Drought Severity Index (PSDI) that the current drought is far worse in terms of its severity to any other drought since the 1890’s. The Palmer Drought Severity Index is an excellent long term indicator of drought as it takes account of both rainfall and evaporation. The index is nearly twice as severe in the current drought as the next worst recorded Federation drought and far greater than the other droughts over this period. The current drought has lasted longer that the Federation drought and isn’t over yet. This study did not link the current drought to climate change, but it certainly quantified it’s severity in comparison to earlier droughts and its corellation with the indian ocean dipole.
On the issue of the bureau’s wrong prediction of lower rainfall in the south east. The bureau provided an estimated probability of the rainfall based on weather modelling. They didn’t say it wasn’t going to be wet, they simply stated a probability that it was slightly more likely to be dry. Anyone with a ounce of statistical nouse knows that a high probability item does not rule out a low one and that the notion of being wrong about a stochastic process is an extremely immature approach to the topic. I would propose on this basis that there are some great developmental opportunities for this particular writer.
It’s all part of growing up.
DAVO101: ‘I’m sorry, what was the point of this article? Is the author a AGW “denier” or “believer”? I can’t really tell.’
Davo you just can’t believe there might be a rational person left who’s not a card-carrying partisan in the AGW civil war, can you.
Well done Frank. The first person in a long time who has said anything interesting about the weather, or the climate, without bible-bashing me in the process.
Robert Garnett, if climate science is so mature, how come we hear almost nothing about relationships between rainfall and ground-surface properties like vegetation. Even though changes in these ground surfaces should be relatively easy to measure in recent decades of geosensing.
Robert: What the BoM meant is quite clear. In you words:
“They didn’t say it wasn’t going to be wet, they simply stated a probability that it was slightly more likely to be dry.”
And they were wrong, but my point is that probability predictions are pretty useless even when they turn out to be right, which at values within say 20% of the mean is going to be more or less half the time. Vague and unreliable. After more than 30 years on the land I’ve never seen any systematically useful long-term predictions. They pop up everywhere in the rural media and farmers just smile. If for example they punt on a crop because of an encouraging long-term forecast, they’re likely to come a cropper.
As for the Indian Ocean dipole etc, I mentioned oceanic temps as the beginnings of understanding of at least that climate driver. The Incas knew about El Nino and La Nina for centuries of course. At least this variable gives forecasters a chance of predicting something useful. But as this year’s predictions show, forecasters still don’t know if an El Nino is imminent or, if it appears, whether it will suppress rainfall (not every El Nino does).
And as for the severity of past droughts, we all know this one is the worst on record for the M-D basin the SE axis (Adelaide-Hobart). My point is that 150 years of records doesn’t preclude this drought being part of a longer cycle, and tells us nothing about the future whatever- because we don’t know why this drought is worse.
To say that “reporters aren’t scientists”, therefore it’s OK to report qualified opinions as “proof”, is disingenuous. Melissa Fyffe was the environment reporter for The Age before her current job description. She’s supposed to know the difference, as all reporters should, between categorical statements and qualified ones. It’s patronising to assume otherwise.
Genuine climate change evidence is devalued by spruiking overstated claims or claims based on individual weather events.