The Canberra Times has a front page article on 15 January 2011 – “Canberra should batten down the hatches” – and talks of “…predicting devastating storms and unrelenting rain in the capital for the next two months.” The ACT SES Commissioner Mark Crosweller said a long-range briefing provided by the Bureau of Meteorology in November had so far proven eerily accurate and the same forecast predicted that Canberra would be battered in late January and February.
OK – so better bring the boat back from the coast.
However, I see on the 29 December the BoM was quoted in a Canberra Times article – “Emergency services prepares for heat” – saying that, “We should see a lot more days around the 30 degree mark around the next two months…”. OK – and I thought it was called Summer !!
As it turned out there were, as predicted, four days 30 and over at Canberra Airport following the 29th Dec. But what the BoM did not predict was that the next 12 days ranged between 20-28 and averaged 24.25 degrees. The 15th & 16th Jan were over 30 again.
We all know it is common in Canberra summer for afternoon storms to capriciously dump a bit of rain here and there.
But “…devastating storms and unrelenting rain…” – does not sound to me to be compatible with – “…a lot more days around the 30 degree mark around the next two months…” – but we shall see what summer brings – and there may be surprises as usual.
I note at the ACT Emergency Services Agency the “..eerily accurate…forecast…” in November 2010 – plus multi times a day local forecasts by the BoM – just up the road – did not help avoid rain damage to their new HQ on 3 December.
Golly – weather is tough to predict.
That Canberra institution – the RiotACT blog also comments on the Canberra Times article in – “More flooding foreseen for the Canberra region”.
What has been the truth about Canberra weather half way through this summer ? – simply wet and cool. Dec at Canberra Airport saw 188.4mm rain or 350% of the average of 53.8mm and daytime temperatures averaged 24.3 compared to the average of 26.1. January to the 16th has seen 48.8mm of rain or 82.4% of the average of 59.2mm – and daytime temperatures averaged 26 or 2 degrees under the average according to Australian Weather News.
If anybody can share any November briefings the BoM was giving to Emergency Services in SE Australia – I would appreciate seeing. Finally, I do not see any warnings for the ACT on this BoM webpage.
Perhaps somebody can translate all these media signals better than I can.
Warwick
Perhaps the Emergency Guys are reading the “politically” correct medium & long term predictions which BoM puts out embellished with diabolicals!( eg the March 2010 state of the climate effort )
Dr Tim Ball has an article on the Qld floods canadafreepress.com/index.php/article/32223
final paras:
I chaired the first attempt to establish a management strategy for the Assiniboine River and drainage basin in Canada (Figure1). As usual it was an extreme event that triggered a conflict – it was typical of the ongoing practice of crisis management. The extreme was caused by the drought across western North America in 1988/89 that was in the same pattern of the 1930s drought. Conflict developed when water flow in the Assiniboine River reached the lowest flow in 94 years of record. In 1996, the worst flood in 101 years was recorded. It was valuable because I could more easily convince Board members that any strategy must consider the extreme variability.
Engineers and hydrologists, among others, deal with what is called the recurrence frequency. When planning they determine what level of natural events will set the limit for their design. It is described as a one-in-100 event, but the second number can have any value. Usually the design is limited by the length and accuracy of the record and cost. The difficulty is, if an event exceeds the limit, then the disaster is exacerbated. The approach assumes the record is adequate in length, which it isn’t. It assumes the range of the record is consistent because they assume the weather is the same over long periods of time. All this ignores the third critical measure of statistics, the variation. Global warming alarmists have claimed the weather is more variable, but more variable than what? Variation changes occur all the time and has increased because of cooling not warming as the cold air of Antarctica expands.
There are human factors involved in the Brisbane flooding. Apparently a dam designed for flood control was allowed to fill with limited release. “We need a full inquiry into why this dam managed by SEQ Water, and others managed by Sunwater, were managed in a way that actually produced the kind of flood it was designed to prevent.”
Another problem, learned from our research of the Assiniboine Basin, was the pattern caused by the wet and dry cycle, as in Queensland. During wet periods, demands are for flood control by dams and drainage ditches. In dry periods the demand is opposite. Now storage and prevention of runoff is required. These systems can serve dual purposes but it requires knowledge of the extremes and management that anticipate the swing from one to another. This is limited by the failure to understand that the records used are totally inadequate in length, trend and variability. I am grateful to Professor Stewart who drew attention to three papers that address the problems. His 2004 paper, “Multi-decadal climate variability, New South Wales, Australia.” A joint paper with Danielle Verdon, “Long-term behaviour of ENSO: Interactions with the PDO over the 400 years inferred from paleoclimate records” And a third paper with Anthony Kiem and George Kuczera titled, Multi-decadal variability of flood risk.”
Living In High Risk Zones
Finally, there is the problem of people being allowed to live in high-risk zones, such as flood plains. Often these zones are ill identified because of the lack of understanding of the true cyclical climate pattern. Maybe people shouldn’t be allowed to live in flood plains, especially at the first flood stage level, but that’s another subject.
I notice on front page of Canberra Times 24 Jan 2011 more mention of this prediction of, [Wild weather is set to hit the ACT for the next six to eight weeks.] A politician, Joy Burch is repeating it on page 4, telling people to “batten down the hatches”.
Things seem quiet around here, days near 30, every week or so the odd shower keeps the weeds thriving..
Any ideas where the prediction comes from WSH ?