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Links to follow developments : BOM map and updates; Yasi Twitter feed compiled by ABC
The frightening power of even a modest cyclone has to be experienced to really understand just how big a threat such a weather event poses. Having been through a couple of small-ish cyclones in Darwin myself (but thankfully not Tracy), my thoughts are very much with people in north Queensland today as Cyclone Yasi approaches.
That’s especially the case because the 2 academics sitting in the offices immediate adjacent to me here at CDU, Shaune and Tanjil, have recently relocated here from Cairns and haven’t sold their house there yet. Fortunately it isn’t in a cyclone surge zone but it’s an old Queenslander that probably isn’t built to current cyclone code, so it might well suffer major damage if the winds hit Cairns at anywhere near Category 5 intensity (280-300kmh). It currently looks very likely that very destructive winds WILL hit Cairns even though the most likely path at present takes the centre over Innisfail just to the south, because Yasi is so large that very destructive winds will extend a long way north and south of the centre.
Even newer houses built to current Building Code may well be at risk from a Category 5. Apparently new houses in north Queensland have been required since 1982 to be constructed to withstand Category 4 winds (200 kmh or thereabouts), but that may not help if the winds are 30% stronger than that. There’s a recurring controversy here in Darwin as to whether our Building code should require engineering new buildings to Category 5 standard, because here too the Code only requires Category 4 despite the devastation of Tracy (whose strength no-one knows for sure because it destroyed all the measuring intrumentation!).
Personally I don’t have a problem with only requiring building to Category 4 on ordinary precautionary principles. The probability of being hit by a Category 5 appears to be relatively low, it’s much more expensive to engineer to Category 5, and in a worst case scenario losing your house isn’t the end of the world as long as you’re adequately insured and take your precious photos and the like with you when you evacuate. Problems only occur if you unwisely decide to stay put in a house whose survival in a large cyclone is questionable, or if you leave your departure until too late. That happened to us in one of the Darwin cyclones we went through. A tree blew down across our driveway just as we were about to evacuate to a city hotel for the duration, so we had to stay put. It was fairly nerve-racking given that the house where I then lived was only a couple of metres above sea level and right on the waterfront. Fortunately that cyclone veered off and missed Darwin.
The real scandal with Queensland’s preparations for Cyclone Yasi appears to be the lack of public cyclone shelters engineered to withstand a category 5:
JUST one cyclone shelter has been built since the State Government promised four years ago to provide safe havens in every community from Cooktown to Bundaberg.
With Queensland facing the worst cyclone season in 40 years, The Sunday Mail can reveal that only Innisfail will have a shelter to house evacuees during a Category 5 storm.
Unlike the politically confected scandal about the operation of Wivenhoe dam in the lead-up to the recent Brisbane floods, the Labor government’s failure to construct adequate cyclone shelters is genuinely reprehensible. I’m sure we’ll hear much more about this issue if Yasi’s impact is as drastic as many fear. If I lived in or around Cairns or Innisfail I think I’d be jumping in the family car and heading west or south as fast as I could. However, if tens of thousands make the same decision that could result in bumper to bumper traffic on the Bruce Highway with many being trapped in their vehicles as the cyclone hits. That’s why the failure to build adequate public cyclone shelters is so potentially serious an omission. It may leave many thousands of people without a viable survival or escape option.
The other big issue in Yasi may be cyclone surge. The BOM map at the time I’m writing this post suggests Yasi’s most likely path will take it almost directly over Innisfail, a town of about 9,000 people (total population around 19,000 including surrounding settlement) some 80km south of Cairns, and crossing the coast around midnight tonight (Wednesday). That’s about 3 hours after a fairly moderate high tide of 2.4 metres. That will certainly result in some inundation of low-lying areas around Innisfail, but if it hits a little earlier and a little further north then the Cairns CBD itself could be inundated. That might not sound too dramatic, but we’re not talking here about relatively flat if fast-flowing waters like those we saw invading the Brisbane CBD only a couple of weeks ago. Tidal surge is in many ways the most destructive aspect of a large cyclone. If they get a 3 metre surge on top of a 2 metre high tide that would take water into the Cairns CBD with waves conceivably as large as 5-6 metres breaking on waterfront city buildings.
That could make the property damage of the Brisbane floods look like chicken feed, and certainly suggests the Gillard government might be wise to revisit Tony Windsor’s proposal for a permanent natural disater relief fund. No-one can say that either the Brisbane floods or this cyclone is a consequence of global warming, but the science indicates unequivocally that global warming will result in more frequent and more extreme weather events including floods, fires and cyclones. Some will be of a size that strains the capacity of government to fund relief and rebuilding efforts without significant fiscal impact.
Anyway, let’s cross our fingers for north Queensland.
Agree with your concluding paragraph. Policy making out to be taking a longer view, taking account of the increased risks that the impact of climate change are going to present us with.
Good Lord.
Spambots have just crossed the line, for mine.
She/it is half right though – this little southerner is thinking nice, calming thoughts for the north.
“No-one can say that either the Brisbane floods or this cyclone is a consequence of global warming, but the science indicates unequivocally that global warming will result in more frequent and more extreme weather events including floods, fires and cyclones.”
Well some whitefella only weather history-
http://www.bom.gov.au/wa/cyclone/about/extremes.shtml
and one storm in particular I recall because my father was a surveyor for ANR at the time, called out to Zanthus(a railway siding near Kalgoorlie) to gauge the risk to the new Trans line. Tracy’s ugly stepsister Trixie-
http://www.bom.gov.au/cyclone/history/trixie.shtml
“The wind gust of 246 km/h at Onslow is the highest recorded on an anemograph in Australia…”
1700km that water travelled across the arid interior, evaporating and soaking away until its remaining Sydney Harbors swept away the best laid flood proofing of Trans Australian railways engineers as it poured into the Bight. That was around the time we were being warned of the next Ice Age while a century ago Dorothea Mackellar waxed lyrical about it all. Pity we don’t have more poets and less 24 hours news cyclists where each event is more traumatic and disastrous than anything prior.
I should add the old man had some great pics of that section of the Nullabor looking like an ocean with a rail line disappearing into it. The Trans line made a great barrage for a while and after all the Sydney Harbours drained away the engineers decided it was a once in a century event which couldn’t possibly be engineered for, so added a bit more bridging to the repair job in the full knowledge it couldn’t cope with any such repeat event. It did spawn the idea of bringing Kimberley water to Kalgoorlie via a canal in future should there be any loose change from NBNs, etc. Snowy in the West anybody?
Whitefella cyclone history on the other side of the continent-
http://www.bom.gov.au/cyclone/history/wa/onslow.shtml
which is easy to forget when so few whitefellas live there.