Cliff Ollier makes 3 statements which he says refute the notion that global warming is in any way connected with the Queensland floods of 2010/11. He says that:

1. scientists are not agreed on the causes of the floods and that it is difficult to attribute global warming to a single climate event:

You may disagree with my view that increasing CO2 emissions are largely responsible for global warming. That does not mean that global warming is not happening. Indeed you can only prove it isn’t by ignoring empirical evidence which shows that it is.

Scientists disagree over many things but that fact does not mean there is no evidence which clearly points to the effects of global warming having some connection with the floods.

We know that sea surface temperatures around Australia have been at a historic high and that globally, 2010 has been the second hottest in the hottest decade. That heat has drawn moisture from the ground into the atmosphere, causing drought conditions over much of Australia. High moisture content strengthened the effects of the strong La Nina which became established in 2010. That combination produced the torrential rains resulting in the Queensland floods of 2010/11.

2. floods have occurred before CO2 induced global warming, so you can’t blame it for the floods which have just occurred.

Floods have indeed occurred in Brisbane before global warming was evident. The worst of these occurred in 1893 and 1974. Those floods resulted from large cyclonic rain depressions. The 2010/11 floods did not. They were caused by very high moisture in the lower atmosphere being concentrated and falling as torrential rain over a vast area of the State.

This was not just a Brisbane flood. Over 40 towns and cities were flooded, killing people and destroying food crops, property and livestock.

We should ask ourselves how such high moisture content got into the atmosphere. The answer is that high temperatures evaporated surface water from both land and sea. What caused those high temperatures?
Global warming - or some other cause Cliff Ollier does not explain?

3. Global warming can not be responsible for both drought and floods.

Anyone can make such statements but when a scientist does so he is required to offer proof of what he is saying. Cliff Ollier offers none.

In any case he is wrong. Warming climate increases the risk of both drought and floods but at different times and/or places. For example in 2002 Europe suffered from widespread floods, followed in 2003 by drought and record heat waves which killed 35,000.

There is growing empirical evidence that warming temperatures cause more intense hurricanes, heavier rainfalls and flooding, increased conditions for wildfires and dangerous heat waves.

In one respect, Ollier is right. It is difficult to attribute global warming as the cause of a single climate event. Here we are no longer talking about a single, isolated event but rather a growing number of severe climate events, all of which have one thing in common – global warming and its effects on other factors which determine climate and weather.

Several bloggers have referred to warming ocean currents having played a part in the recent floods. The BoM however, says that there is no warming at present; that we are in the midst of a La Nina which is actually a cooling event.... http://www.bom.gov.au/climate/ahead/ENSO-summary.shtml

And it will contnue they reckon for several months yet.

Other ACC acolytes,and general scaredy-cats, have tried to make out that all the dough given to the BS scamsters investigating their favourite delusion has allowed them to somehow predict a Bad Moon Risin', and trouble on the way. Which then leads to the claim that we should do something about it!!

OK. So all the Penny Wongs who threw money around because the Murray Darling...and all other rivers in Australia....would be bone-dry forever were doing the right thing eh? They were accurate weather/climate predictors as a result of the money given to every Climate Change scamster with their hand out, eh?

Most interesting in all this, is that the bloggers here who now reckon they saw the rain coming...because that's what the theory says...never told us (or Penny, or Kevvy, or Greg, or Peter)what they now reckon was all so clear. When all those ALP/Green idiots were telling us the drought was permanent, the "legends" on this blog weren't setting them straight.

Hmmm. At the racetrack when some tipster gets it wrong...and then says "yeah I knew that other one would win" I don't pay them much attention. I certainly wouldn't be comfortable with a tipster telling me that his "Computer-based modelling" had shown that every horse will win!!

I suppose I haven't got the DNA to be that gullible; explains why I'm not happy paying billions to scamsters who can only tell me "the weather may or may not be different next year" either. Cheers.

Punter57
You misread BOM - perhaps unintentionally.

http://www.bom.gov.au/climate/glossary/lanina.shtml

Australia lies in the western Pacific Ocean (not central or eastern).

You also seem to confuse sub surface ocean temperatures with sea surface temperatures.

This is is the temperature profile off the coast of Australia for the last few months.

http://www.bom.gov.au/climate/enso/sub_surf_mon.gif

Sub surface ocean temperatures have been getting warmer (look at the red bits). It has been higher than normal.

La Niña events for Australia does mean increased rain. Warmer waters off the coast, coupled with a string of low pressure cells, make even more rain. Walker and Hadley cell activity have exacerbated an already tenuous situation.

The potential for extreme floods are higher than normal - you can bet on it.

If punters (including politicians from all persuasions) don't want to look at the odds given by BOM, so be it. They'll lose.

NEVER BET ON ANYTHING THAT TALKS

Hey bonmot

"If punters (including politicians from all persuasions) don't want to look at the odds given by BOM, so be it. They'll lose."

Will the weather in 2015, 2020, 2050 or 2100 be fine, cold or apocalyptic? Punters are urged to weigh the balance of probabilities carefully. They should note this track wisdom too: “never bet on anything that talks”.

Alice (in Warmerland)

Warwick Hughes has spotted a neat trifecta: whether it be rain, maximums or minimums, the BOM gets it wrong.

For this spring the Australian BOM predicted it would be dry and warm, instead we got very wet and quite cold. The models are so bad on a regional basis, it’s uncannily like they are almost useful… if they call things “dry”, expect “wet”.

On August 24 the Australian BOM had pretty much no idea that any unusual wetness was headed their way. Toss a coin, 50:50, yes or no. Spring 2010 was going to be “average”, except in SW Western Australia where they claimed “a wetter than normal spring is favoured.” What follows were 100 year floods, or at least above average rain to nearly every part of the nation bar the part that was supposed to be getting more rainfall. In the chart below, all shades of “blue” got above average rainfall. The dark blue? That’s the highest rainfall on record.
The rainfall deciles chart original is here.

http://jonova.s3.amazonaws.com/graphs/australia/australian-rainfall-spring-2010.gif
On August 24 the BOM predicted that spring would be “hot across the north”. Instead it was cold everywhere except in the west of WA.

Australian Spring Maximum temperatures
Warwick Hughes linked to this unusually candid report of BOM seasonal rain forecasts (Vizard 2005). More »

Agnostic of Mittagong - look, I dunno where you got the business about the 70s floods in Brisbane being due to a cyclonic high or whatever it was, but if you look again you'll find its an old explanation. At the time they didn't know about the la nina - el nino cycle so that was the explanation they gave.. both floods are due to la ninas.

ozandy - as I've repeated to the others, no one knows what makes this climate cycle tick so trying to attribute a not so exceptional flood (historical floods have been higher) to high temperatures is a waste of time. As for the IPCC forecasts, the panel most emphatically did not forecast river floods. They equated forecast higher temperatures (which also haven't occured) with droughts.. the Brisbane river should be down to a trickle.. not in flood.