BOM report for autumn 2011. Victoria
http://www.bom.gov.au/climate/current/season/vic/summary.shtml
EXTRACT
Climate > Regular statements

Wednesday, 1 June 2011 - Seasonal Climate Summary for Victoria - Product code IDCKGC26R0
Victoria in autumn 2011: Cold days

* The coldest average autumn daytime temperatures on record for many stations
* Record breaking rain in parts of Gippsland
* Average night-time temperatures mixed and generally close to normal

Extremes Maps Records Summaries Important notes the top
Rainfall

Provisional data indicates that autumn 2011 rainfall was close to normal for most of Victoria. The exception to this was parts of Gippsland were rainfall was well above average. Mount Baw Baw recorded the largest total for the season with 542.0 mm. Several stations in West Gippsland recorded their highest total autumn rainfall on record. Parts of the state recorded above average rainfall during March and then most of the state recorded close to average rainfall during April and May. The wettest single day of the season was the 23rd of March when Thorpdale Peak recorded 139.8 mm. Some sites had their highest autumn daily rainfall on record. There is a map of rainfall deciles below.

Your neck of the woods ( atleast the Nth side of the Macedon Ridge is about to receive another WNW originating downpour .
I believ your above comment is Premature , It will happen . These NW cloudbands are only just starting to kick into gear .

Yeah bit premature there Andrew still a while to go before Winter comes and goes and also Autumn wasn't below average as you can see on that map plenty of while and more Blue than Red on the Vic decile map for 2011 for Victoria

The rainfall for Autumn was significantly boosted by a very wet March on the tail end of the summer wet season:



Since April it has been drier, although still some good rains in coastal areas:

Despite a late forming and weak La Nina winter rainfall in Australia was below average, to continue a weak recent trend of reduced winter rainfall:



In contrast November rainfall continues a fairly significant trend towards higher rainfall.



And for Spring:



The predicted trends for AGW are for significant drying during winter and spring, particularly in the South, and a slight increase in rain for summer and autumn, particularly in the north.

They are now Mike but what about the fact that we were all told Australia was going to experience neverending drought. And don't try to deny that this was the case. In a few years when the winter rainfall is slightly above average and the summer rainfall 'particularly in the north' are well below average are you not just going to turn around and claim this is what was predicted all along. The biggest problem with AGW and it's effects has been the constant grabbing of one particular idea that at the time seems likely and beating up to the point where everyone is positive that they only have months to live. Then when it doesn't happen it is claimed that this idea was never intended and that something else was the more likely. Ever heard of the 'boy that cried wolf'. Stop telling us that things are happening to us because of AGW. All I see in your graphs is a natural variation of rainfall and certainly not any obvious an unambiguous trend.

Trends? I see absolutely no trends there, natural variation as Brett mentioned in his post which i very much agree with.

This thread started in 2009, and I am comparing these trends to predictions that were noted at the start of this thread. The predictions of never-ending drought are media sensationalism and was never reflected in the scientific literature.

2007 CSIRO; "New projections for Australia’s changing climate"

ROM, even in that statement she's hedged her bets. 20-30 percent annual decreases in rainfall, but when it does rain it's going to be "more intense".

Honestly, the predictions of AGW impact are nearly the same as a fortune teller. "You may meet interesting people, but you may meet boring people too"...

Global warming signature in Australia's worst drought

James Risbey1, David Karoly2, Anna Reynolds3, Karl Braganza1

Bulletin of the Australian Meteorological and Oceanographic Society Vol. 16 page 8

Never ending drought is very different from an increase in drought.

To some extent this is correct. If you go back to the projections I refer to in my original post, you can see the model range of projections include a span from decreasing rainfall for all of Australia, to increasing rainfall for all of Australia.

Projections of drought are primarily based on the fact that the models seem to show a slight bias with more showing drying then increased rainfall, so the middle case is drying.

That and the fact that if rainfall stays the same and temperatures increase, then evaporation will increase and result in a strengthening of droughts without any decrease in rainfall.

However one aspect which appears to be more consistent in the models is a bias towards wet conditions in the summer and north, and dry conditions in the south and winter. Models which show overall drying show it more intensely in the south and during winter, and models which show overall increased rainfall show the increases are strongest in the summer and in the north.

And those are all valid interpretations of the models. But then you have statements from the likes of Tim Flannery. These are just some direct quotes from him (circa 2008):

“The water problem is so severe for Adelaide that it may run out of water by early 2009.”
“water supplies are so low (Brisbane) need desalinated water urgently, possibly in as little as 18 months”.
“there is a fair chance Perth will be the 21st century’s first ghost metropolis”.

In all three you have the scientific hedge betting probability statements "may", "possibly" and "fair chance". But he says those things knowing full well the person he speaks to will ignore that and run the story about ghost cities, capitals running out of water etc. And the problem is it's not just journalists selling papers and ratings, he has done the same thing with politicians which leads them to spend (read: waste) taxpayer dollars.

Brisbane has been a debacle. The SEQ water grid has made good sense, linking the major dams, but the money spent on a desalination plant that fell apart as soon as it was commissioned, and a recycled water plant they decided they didn't want to use when the rains that weren't meant to come did...money that could've been spent on a dam on the Bremer river which contributed to devastating flooding in Ipswich this year.

This is the problem. Scientists have a huge influence on public policy at the moment and while they cover their arses by using "may", "possibly" etc, their predictions are triggering major government response that is sometimes illconceived and/or poorly executed.

And to avoid a counter argument, yes, sceptical scientists/commentators can be just as bad in saying things like "global warming may have stopped altogether and CO2 may not have much to do with it"...there's that "may" again...

Well said, Coxy!

And just in case anyone thinks Tim Flannery is a climate scientist, the wikipedia has this to say about him:



(article)

I do realise he's not a climate scientist, but he is "marketed" that way, as a global warming expert. He is the head of the Australian Government Climate Change Commission...

His opinion is often sought as a counter to those of actual (though sceptical) climate scientists like Pielke and Christy.

"It's important to note that although some climate change is inevitable, changes of the magnitude described here are still avoidable as long as we are able to significantly reduce global greenhouse emissions," said Penny Whetton, the senior principal research scientist leading the Better Scenarios project with the CSIRO Climate Adaptation Flagship in Clayton South, Victoria.

Discovering the changes

Researchers from the CSIRO and the University of Melbourne analysed the predictions of 23 currently available global climate models using data from the Coupled Model Intercomparison Project, a project that gathers data from around the world to make predictions on changes in world climate.

A statistical tool called a 'probability distribution model' was applied to the projected changes predicted by the models to find what changes would occur at certain levels.

These probability distribution functions were scaled to match scenarios of global warming for 2030 and 2070.

Climate predictions then and now

Previous projections by the CSIRO and the Bureau of Meteorology in 2007 predicted a temperature increase of at least 1 degree Celsius by 2030. “If emissions are low, we anticipate warming of between 1.5 degree and 2.5 degrees by 2070, with a best estimate of 1.8 degrees,” Whetton said in 2007. “Under a high emission scenario, the best estimate is 3.4 degrees Celsius with a range between 2.2 to 5.0.”

The 2007 report also predicted the effect of increasing levels of greenhouse gases on rainfall, showing decreases in overall and seasonal rainfall across Australia in the decades to come.

The new study gives a more solid prediction to the effects of a global climatic shift. If global temperatures increased by 4 degrees Celsius or more, it would result in temperature increases of between 3 degrees and 5 degrees for coastal areas and 4 degrees to 6 degrees for inland Australia, the report shows.

In addition, global climate shifts would affect precipitation patterns, with snow cover falling to zero in most regions across the Australian Alps. More notably, the annual rainfall over southern Australia, particularly in winter and spring, would decrease by up to 50%.

"Unlike anything experienced before"

The combined decrease in rainfall with rising evaporation levels of between 5% and 20%, would lead to droughts occurring up five times more often in the southern regions of Australia, the study said."


If you ask Australia’s national science agency, the CSIRO, about climate change, the outlook is bleak. By 2030 rainfall on the major capitals (except Hobart) could drop by 15 per cent. According to the 2001 report, Climate Change Projections for Australia, Perth could loose up to 20 per cent of rainfall. At the same time, rising temperatures will increase evaporation, further reducing water supplies in dams, rivers and reservoirs.
In another recent scientific report by the same agency, which examines water price implications for each of Australia’s main cities and regions in 25 years’ time, the real price of water could skyrocket.

The 2006 report, Without Water: The economics of supplying water to 5 million more Australians, says if governments do not act to expand water trading and access ‘new’ sources of water such as building desalination plants, establishing large sewage recycling schemes and making use of storm water, the price of water would increase by between five and ten times in large cities to manage demand."

http://www.climatechange.com.au/tag/drought/

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.

A three-year collaboration between the Bureau of Meteorology and CSIRO has confirmed what many scientists long suspected: that the 13-year drought is not just a natural dry stretch but a shift related to climate change.

Scientists working on the $7 million South Eastern Australian Climate Initiative say the rain has dropped away because the subtropical ridge - a band of high pressure systems that sits over the country's south - has strengthened over the past 13 years.

Advertisement: Story continues below These dry, high pressure systems have become stronger, bigger and more frequent and this intensification over the past century is closely linked to rising global temperatures, they found.

Climate data from across the past century shows the subtropical ridge has peaked and waned, often in line with rising global temperatures.

But to see what role greenhouse gases played in the recent intensification, the scientists used sophisticated American computer climate models.

When they ran simulations with only the ''natural'' influences on temperature, such as changing levels of solar activity, they found there was no intensification of the subtropical ridge and no decline in rainfall.

But when they added human influences, such as greenhouse gases, aerosols and ozone depletion, the models mimicked what has occurred in south-east Australia - the high pressure systems strengthened, causing a significant drop in rainfall.

''It's reasonable to say that a lot of the current drought of the last 12 to 13 years is due to ongoing global warming,'' said the bureau's Bertrand Timbal.

''In the minds of a lot of people, the rainfall we had in the 1950s, 1960s and 1970s was a benchmark. A lot of our [water and agriculture] planning was done during that time. But we are just not going to have that sort of good rain again as long as the system is warming up.''

http://www.theage.com.au/national/its-no...90829-f3cd.html