Eight reasons why this current heatwave is a boring, overhyped example of weather being used for political purposes.
1. It’s the long term trends that matter — not a few weeks of hot weather
As climate scientists keep telling us (except when they have a heatwave to milk), “weather is not climate”. It’s the long term trends that matter. One short four week period is not a long term climate trend, but it is an excellent opportunity to create hype and scaremongering in the newspapers. Scientists with little scruple and low standards are making the most of this.
2. The “records” we are breaking are pitifully short
Even if this is the hottest heatwave “ever recorded”, it doesn’t mean much in the long term scheme of things. Natural climate cycles work on scales of 11 years, 60 years, 200 years, 1500 years, and 100,000 years. We have decent temperature records for many locations for only 50 years. We have a scratchy patchy thermometer record for 150 years. Any scientist raving about breaking a 50 year record as if it means something is … embarrassing. There is too much noise in this system and too little data.
3. If a few weeks of extreme heat suggest CO2 is causing a catastrophe, then don’t a few weeks of Siberian record breaking cold suggest the opposite?
Siberians would appreciate some global warming this winter. Cold weather is killing people in Ireland, Maryland, Chicago, Afghanistan the UK and Russia.
4. 50C temperatures have occurred all over Australia before, and without any influence by CO2.
Correlation is weak evidence, and this correlation is so weak, it’s nearly non-existent. The price of postage stamps correlates with temperatures. Australians have been recording temperatures of over 50C since 1828, right across the country. In 1896 the heat was so bad for weeks that people fled on emergency trains to escape the inland heat. Millions of birds fell from the sky in 1932 due to the savage hot spell. Thanks to Chris Gillham and contributors in comments for the detail in this graph.
(click to enlarge)
5. Heatwaves have happened before many times, and there’s no long term increase
Since 1890 our BOM records show that there have been many clusters of five hot days in Sydney and Melbourne. This summer has been bog-standard and ordinary. Thanks to Geoff Sherrington for the idea and the number crunching on these graphs.
Jan 2013 is not over, but so far:
- Sydney‘s highest 5-day average in 2013 is 30.5 (ending on 8th Jan).
- Melbourne‘s highest 5 day average is 32 (ending on 7th Jan). (It’s not even on the chart!)
Heatwaves in January in Sydney and Melbourne, Australia
6. Global temperatures have been increasing for 300 years
Given that our data is shorter than that, it is entirely predictable that we will set “new records” even though the climate is now cooler than it was 5,000 years ago, 130,000 years ago and for most of the history of life on Earth. Our records are short (point 2) the trends are not unusual (point 7) and we aren’t certain what caused the world to start warming circa 1700, but it wasn’t due to CO2. Not too many air-conditioners or SUV’s in King William III’s time.
7. The world is not warming any faster now that it was 140 years ago
Decadal warming trends peaked at about 0.16C three times in the last 150 years. Right now it’s less (close to zero). In other words, current trends could be entirely natural. The world was warming faster in 1870 than it is now. Shouldn’t all that CO2 be increasing the rate?
Hadley Global Temperature Graph with Phil Jones trends annotated on top.
8. People are mixing up cause and effect. Any cause of warming will … cause heatwaves.
Shock us. Just because the world has warmed does not mean it was caused by CO2. If other things were warming the planet, they would cause heatwaves too. (Possible causes include but are not limited too: the solar-magnetic effect, cloud cover changes, or ocean current shifts. Heck it could be aliens with ray guns… the planet will warm.) This is the banal, bleedingly obvious inference any scientist (or graduate of primary school) would make.
What we need is evidence of the cause. Some climate scientists say their computer simulations of the atmosphere show CO2 is the cause. But their models don’t work, can’t predict anything that matters, and no one can find a single published paper showing the assumptions the models use are correct. (I’ve been asking for three years.)
So arctic ice, extreme weather, heatwaves… are not evidence that CO2 did it. And people implying it is, are … confused, dishonest, over-zealous, and not much of a scientist, take your pick.
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Posts on Extreme weather, Heatwaves and Australian temperatures.