Schulte vs Oreskes on consensus, Round 2

While it's all a bit of a storm in a teacup, over a paper that is yet to be published, the Schulte vs Oreskes consensus debate rolls on. In a refreshing development, Schulte himself has posted a reply to Naomi Oreskes' rebuttal. Until now, all we've heard is hearsay reports about Schulte's paper - finally we get it from the horse's mouth. Some interesting factoids emerge:

• Schulte originally submitted his paper to Science which makes sense as Oreskes' paper was originally published there. Science rejected it.
• Schulte's motivation for writing the paper: "I drafted the paper because I had become concerned that patients were being perhaps unduly alarmed by media reports of catastrophic climate change and were coming to harm through resultant stress. [snip] My sole concern in this debate is the welfare of patients." Somehow, I doubt disseminating misleading global warming skepticism is what Hippocrates had in mind when he wrote "do no harm".
• Schulte makes the peculiar point that Oreske's paper is not peer-reviewed. This claim is false. Oreske's paper was originally submitted as a policy forum, but the editors decided to get it peer-reviewed.

Most illuminating is his critique of Oreskes' original paper, claiming several papers in her survey reject the consensus. Schulte quotes almost verbatim from the Viscount Monkton of Benchley who in turn rehashes Benny Peisner's old work. Here are the five studies he cites that Oreskes should've included in her survey as rejecting the consensus position:

• Multi-resolution time series analysis applied to solar irradiance and climate reconstructions (Ammann 2003) finds a correlation between solar activity and temperature. However, the temperature reconstructions used end in the mid-20th century before the modern global warming trend and don't address the consensus position that warming over the past 50 years is primarily anthropogenic. However, Amman has done a more recent study examining more up-to-date temperature records and concluded "although solar and volcanic effects appear to dominate most of the slow climate variations within the past thousand years, the impacts of greenhouse gases have dominated since the second half of the last century" (Ammann 2007).
• Solar Forcing of Global Climate Change Since The Mid-17th Century (Reid 1997) finds a link between solar variability and climate change, concluding that "solar forcing and anthropogenic greenhouse-gas forcing made roughly equal contributions to the rise in global temperature that took place between 1900 and 1955". Considering CO2 forcing before 1955 was much lower while solar forcing was much greater due to increasing solar activity, this conclusion only serves to reinforce the consensus position. More on the sun...
• Ad Hoc Committee on Global Climate Issues: Annual Report (Gerhard 2000) is non-peer reviewed. Oreske's survey only included peer reviewed studies. This is even conceded by Schulte which makes me wonder why he brings it up in the first place.
• Atmospheric Greenhouse-Effect in the Context of Global Climate-Change (Kondratyev 1995) is a review, not an article - it doesn't actually include any research but reviews other studies. Oreskes' survey only included articles, not reviews.
• Review and impacts of climate change uncertainties (Fernau 1993) is another review, not an article, and is found in the Social Science Citation Index. Oreskes sampled articles only from the Science Citation Index.
  

Lastly, I found an interesting quote in the Monkton article that Schulte borrowed from:

"What of the papers showing that solar variability is a key driver of recent climate change, and that in the past 70 years the Sun has been more active, for longer, than at almost any comparable period in the past 11,400 years?"

Ah, that old chestnut! He seems to be refering to Solar Activity Over the Past 11,500 years (Usoskin 2003). If only he'd read right through to the final paragraph:

"During these last 30 years the solar total irradiance, solar UV irradiance and cosmic ray flux has not shown any significant secular trend, so that at least this most recent warming episode must have another source."

Many thanks to Fergus Brown for the heads up on Schulte's response. More on Naomi Oreskes' study...

Posted by John Cook on Sunday, 9 September, 2007

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