Arguments
The Queensland floods
Posted on 12 January 2011 by John Cook
As the Queensland floods have now hit Brisbane, a number of people have emailed or posted comments enquiring about our well-being. Many thanks to everyone for their thoughts and concern. I'm happy to say the Cook family is safe and dry - we happen to be located in a relatively elevated area (not by design - extreme flooding was not even on my radar when we moved into the area). However, many nearby suburbs have not been so fortunate.
Ten minutes south-east from us, low-lying areas of Strathpine were evacuated yesterday. South Pine River has burst its banks and covers a large portion of the suburb:
Meanwhile, to the north-west of us, just down the road from our church, One Mile Creek has also burst its banks and blocked off the road:
Up to 40,000 homes are estimated to be affected by flooding over the next day, when the Brisbane River peaks at 3am tomorrow morning. But while the flood waters rise gradually here, incredible scenes were witnessed earlier this week in the town of Toowomba, 90 minutes west of Brisbane. The media are refering to it as an inland tsunami - a wall of water rushed through the town, dragging along cars, shipping containers and even houses. We heard accounts of entire homes being plucked off their foundations and carried by the waters, with people inside crying out for help. The tragedies this and other Queensland towns have endured are heartbreaking and the damage mindboggling.
When these kind of extreme events happen, people ask "Did global warming cause this flood?" as if the answer should be yes or no. It's more appropriate to ask does global warming have an effect on these types of events? The scientific evidence indicates yes. As temperatures have risen, we've observed more water vapour in the air. More water vapour leads to more extreme rain events. Over the last few decades, we've observed an increase in the number of extreme precipitation events. And we expect the number of extreme precipitation and flooding events to increase as global warming continues.
It's times like this that I can't help thinking of the words of NOAA scientist Deke Arndt, "Climate trains the boxer but weather throws the punches". Weather will always throw these random punches at us. Occasionally it gets in a lucky punch that knocks us off our feet. But what we're doing is training weather to throw harder punches at us and more often. That's what is being observed and that's what we expect to see more of in the future.
Anyone who wishes to help, you can Donate to the Queensland Government's flood relief appeal.
0 
0
Average precipitation over the continent has increased since 1900 by some 20%. Of course it says nothing about the spatial and seasonal distribution of precipitation, but the notion droughts are getting more severe on average is certainly a false one.
Even this increase is not uniform. Most of it happened in a single step of some +66 mm (15%) in 1973, and this level is more or less maintained since then. Interannual variation is huge, but it was always this way in Australia.
It strongly suggests an abrupt climate shift in the first half of the 1970s, which is consistent with what we know about other parts of the globe. Perhaps ocean currents got rearranged a bit around that time, but unfortunately we didn't have our current advanced measurement systems in place to collect data during the event.
It's extremely unlikely the phenomenon has anything to do with CO2, as levels were just 328 ppmv back then and they've increased by 19% in the last 38 years, apparently with no additional influence on interannual Australian precipitation patterns.
Nevertheless I'm weeping for the dead and homeless, even if they're not victims of some man made climate disruption, just cruel weather.
It clearly shows the average SST around Australia over the last decade to be 0.6 degrees C over the 1950's average, and 2010 to be 0.8 degrees C over the 1950's average. The significance is that the final datum in your second source is circa 1950. Therefore Australia's current SST's are approximately 1.8 degrees greater than the minimum at the LIA.
Given that the data from that site are for individual locations, while the Australian data is an average of all Australian waters, we would expect the Australian data to show significantly less variability (as would the data from the other site if averaged). Therefore it is reasonable to conclude that the Australian SSTs are near or at a maximum for the last 2000 years, not just the last 100 years.
Of course, as you well know, it is voodoo science to simply point to a similar range of variability and assume that therefore no explanation is required. Changes require causes, and no non-anthropogenic causes can plausibly explain the late twentieth century warming. In contrast, it is difficult to device a plausible theory of the greenhouse effect in which anthropogenic emissions do not cause warming of similar magnitude that that which we have seen.
In particular, the increase in average rainfall in the north of Western Australia and the Northern Territory clearly dominates the average, but that does not free Queensland and Victoria from their recent trend towards droughts in most years, nor Perth from its ongoing drought even in this wetest ever of Australian years.
Comments