Former “alarmist” scientist says Anthropogenic Global Warming (AGW) based in false scienceDavid Evans has been regularly wheeled out as a 'credible scientist' who has 'changed sides' for years. I remember investigating a list of 13 scientists who had originally supported AGW and now opposed it, back in May 2007 (2).
David Evans is a scientist. He has also worked in the heart of the AGW machine. He consulted full-time for the Australian Greenhouse Office (now the Department of Climate Change) from 1999 to 2005, and part-time 2008 to 2010, modeling Australia’s carbon in plants, debris, mulch, soils, and forestry and agricultural products. He has six university degrees, including a PhD in Electrical Engineering from Stanford University. (1)
THAT'S ALMOST EXACTLY FOUR YEARS AGO.
You'll note that David Evans is on the list, in with a bullet at number 4. So it's with some bemusement that he's still being presented as if he was a sinner who has just seen the light.
Which is all by-the-by if Evans was actually presenting new or interesting criticism of AGW. He indicates that he has some remarkable evidence that shows global warming isn't driven by greenhouse gases at all, and that this evidence has been deliberately ignored by the 'alarmists.'
But what is the 'empirical evidence' that he thinks disproves AGW theory? The lack of a tropospherical 'hotspot.':
What did they find when they tried to prove this theory?That's it. The hotspot issue has been gone over, many times. It's a bollocks argument.
Weather balloons had been measuring the atmosphere since the 1960s, many thousands of them every year. The climate models all predict that as the planet warms, a hot spot of moist air will develop over the tropics about 10 kilometres up, as the layer of moist air expands upwards into the cool dry air above. During the warming of the late 1970s, ’80s and ’90s, the weather balloons found no hot spot. None at all. Not even a small one. This evidence proves that the climate models are fundamentally flawed, that they greatly overestimate the temperature increases due to carbon dioxide. (3)
The 'hotspot' isn't a unique 'fingerprint' of global warming. It's something that happens as a result of warming, regardless of cause. And that, undoubtedly has been going on. It doesn't matter if it is driven by greenhouse gases, solar activity or the Will of Cthulhu. It will lead to the creation of a tropical, tropospherical hotspot - because its fundamental physics that moist, warm air contains more energy, so the lapse rate (how quickly it cools) is lower.
The real 'fingerprint' of greenhouse gas forced warming is a warming troposphere (tick) and a cooling stratosphere (tick). That means the current warming can't be peredominantly driven by the sun, as that would cause both tropospherical and stratospherical warming.
Why this crap is still getting spewed over the interweb is almost as puzzling as Evans' continued status as anew convert to 'scepticism.' Clearly, recruitment must be a bit slow if they still have to hype his dubious credentials as an ex 'alarmist.'
Nothing to see here, move right along.
1 - "Former “alarmist” scientist says Anthropogenic Global Warming (AGW) based in false science," by Bruce McQuain. Posted on Hot Air, 15th of May, 2011. (http://hotair.com/archives/2011/05/15/former-alarmist-scientist-says-anthropogenic-global-warming-agw-based-on-false-science/)
2 - As described previously on lefthandpalm: http://lefthandpalm.blogspot.com/2007/05/more-crap-about-climate-change.html
3 - "Climate models go cold," by David Evans. Published in The Financial Post, 8th of April, 2011. (http://www.financialpost.com/news/Climate+models+cold/4579652/story.html)