Hypothesis Testing – A Failure In The 2007 IPCC Reports

In my post

Short Circuiting The Scientific Process – A Serious Problem In The Climate Science Community

I wrote

There has been a development over the last 10-15 years or so in the scientific peer reviewed literature that is short circuiting the scientific method.

The scientific method involves developing a hypothesis and then seeking to refute it. If all attempts to discredit the hypothesis fails, we start to accept the proposed theory as being an accurate description of how the real world works.

A useful summary of the scientific method is given on the website sciencebuddies.org.where they list six steps

• Ask a Question
• Do Background Research
• Construct a Hypothesis
• Test Your Hypothesis by Doing an Experiment
• Analyze Your Data and Draw a Conclusion
• Communicate Your Results

Unfortunately, in recent years papers have been published in the peer reviewed literature that fail to follow these proper steps of scientific investigation. These papers are short circuiting the scientific method.

In the recent report

“Climate Change Assessments, Review of the Processes & Procedures of the IPCC“ 

within the section titled

IPCC’s Evaluation of Evidence and Treatment of Uncertainty

it is written [boldface added]

The IPCC uncertainty guidance provides a good starting point for characterizing uncertainty in the assessment reports. However, the guidance was not consistently followed in the fourth assessment, leading to unnecessary errors. For example, authors reported high confidence in statements for which there is little evidence, such as the widely-quoted statement that agricultural yields in Africa might decline by up to 50 percent by 2020. Moreover, the guidance was often applied to statements that are so vague they cannot be falsified. In these cases the impression was often left, quite incorrectly, that a substantive finding was being presented.”

My comment on the publication process in the post

Short Circuiting The Scientific Process – A Serious Problem In The Climate Science Community

fits and can be rewritten as

What the current IPCC assessment process has evolved into, at the detriment of proper scientific investigation, is the inclusion of untested (and often untestable) hypotheses.  The fourth step in the scientific method“Test Your Hypothesis by Doing an Experiment” is bypassed.

It is written in the IAC Review of the IPCC report that

“…the guidance was often applied to statements that are so vague they cannot be falsified.”

This is a correct conclusion and also applies to the predictions decades from now as presented in the 2007 IPCC report.

These also cannot be falsified.

The acceptance of hypotheses as facts in the publication process including the IPCC assessments is a main reason that the policy community is being significantly misinformed about the actual status of our understanding of the climate system and the role of humans within it.