IPCC´s “Guidance note on expression of uncertainty” is a particularly important governing document for IPCC. The document affects all the working groups. There are two main themes in the guidance note on expression of uncertainty:
– Qualitative expression of confidence
– Quantified measures of uncertainty
InterAcademy Council gave bad advice on both.
This post is about Qualitative expression of confidence.
(Here is the post about: Quantified measures of uncertainty:
Both IPCC and it´s reviewer, InterAcademy Council, messed up on “Quantified measures of uncertainty”!)
Recommendations from the InterAcademy Council on “communicating uncertainty”
On 10 March 2010, the Secretary-General of the United Nations Ban Ki-moon and IPCC Chair Pachauri requested InterAcademy Council (IAC) to undertake a review of the processes and procedures of the InterGovernmental Panel on Climate Change.
The report was published in October 2010:
Climate Change Assessments, Review of the Processes & Procedures of the IPCC (2010)
From the foreword it is clear that InterAcademy Council recognises the importance of proper handling of scientific uncertainty, and that the consequences are of great importance to humanity:
Recognizing that the issue of climate change is of great importance to humanity, is complex in regard to scientific uncertainty, and has potential long-term consequences, the IAC Board agreed to undertake this review.
The importance of uncertainty is further evident as recommendations on the communication of uncertainty is one of the most significant key recommendations by IAC.
The Committee’s main recommendations relate to IPCC’s governance and management, its review process, characterizing and communicating uncertainty, communications, and transparency in the assessment process.
Everything should be lined up for IAC to give United Nations proper advice on the expression of uncertainty then. The advice from IAC on the expression of uncertainty are summarised in the section “Characterizing and communicating uncertainty”:
Recommendation: Each Working Group should use the qualitative level-of-understanding scale in its Summary for Policymakers and Technical Summary, as suggested in IPCC’s uncertainty guidance for the Fourth Assessment Report. This scale may be supplemented by a quantitative probability scale, if appropriate.
– Page xv
InterAcademy Council recommends United Nations climate panel IPCC to use a qualitative level-of-understanding scale to characterize and communicate uncertainty.
IPCC´s confidence scale
These recommendations influenced the revision of the IPCC document:
Guidance Note for Lead Authors of the IPCC Fifth Assessment Report on Consistent Treatment of Uncertainties … 6-7 July 2010
In annex B it is stated:
Annex B: Addressing the InterAcademy Council Recommendations
The 2010 independent review of the IPCC by the InterAcademy Council (IAC)3, released on August 30, 2010, included six recommendations related to the evaluation of evidence and treatment of uncertainty in IPCC reports. These recommendations are listed below, with brief summaries explaining how the AR5 guidance addresses their key elements.
(And don´t ask me how a review released August 30, 2010 can be taken into account in a guidance document dated 6-7 July 2010. I have no idea how that came about.)
The guidance notes are intended to address the recommendation by IAC. The following figure summarizes the language imposed upon the lead authors of the fifth assessment report by IPCC to express “Qualitative expression of confidence “:
Everything should be perfectly fine then: Inter Academy Council advices IPCC that “Each Working Group should use the qualitative level-of-understanding scale in its Summary for Policymakers and Technical Summary, as suggested in IPCC’s uncertainty guidance for the Fourth Assessment Report.” and – IPCC follows that advice and impose the qualitative level of understanding scale upon it´s lead authors.
Well – it might seem that everything is perfectly fine, but anyhow – there is a severe problem. There is an obvious problem with the qualitative level-of-understanding scale used by IPCC: It is subjective!
A qualitative level of confidence is in the eye of the beholder – a qualitative level of confidence cannot be exposed to testing – it cannot be falsified.
However – there is no need to re-invent the wheel to put forward a critique on qualitative level-of- understanding. Let me introduce Karl Popper. Karl Popper was the man who understood, explained and described the scientific method to us.
Sir Karl Raimund Popper CH FBA FRS (28 July 1902 – 17 September 1994) was an Austrian-British philosopher and professor. He is generally regarded as one of the greatest philosophers of science of the 20th century.
Popper is known for his rejection of the classical inductivist views on the scientific method, in favour of empirical falsification: A theory in the empirical sciences can never be proven, but it can be falsified, meaning that it can and should be scrutinized by decisive experiments…
If the outcome of an experiment contradicts the theory, one should refrain from ad hoc manoeuvres that evade the contradiction merely by making it less falsifiable.
Popper is also known for his opposition to the classical justificationist account of knowledge, which he replaced with critical rationalism, “the first non-justificational philosophy of criticism in the history of philosophy.”
– Wikipedia – Karl Popper
The problem with IPCC´s qualitative level-of- understanding is best illustrated by a quote from Karl Popper in The logic of scientific discovery.
“a subjective experience, or a feeling of conviction, can never justify a scientific statement … No matter how intense a feeling of conviction it may be, it can never justify a statement. Thus I may be utterly convinced of the truth of a statement; certain of the evidence of my perceptions; overwhelmed by the intensity of my experience: every doubt may seem to me absurd. But does this afford the slightest reason for science to accept my statement? Can any statement be justified by the fact that Karl Raimund Popper is utterly convinced of its truth? The answer is, ‘No’; and any other answer would be incompatible with the idea of scientific objectivity.”
– Karl Popper – The logic of scientific discovery
Likewise – Can any statement be justified by the fact that IPCC is utterly convinced of its truth? The answer is, ‘No’; and any other answer would be incompatible with the idea of scientific objectivity.
There is no need to elaborate further on Karl Popper writings in this post. His main work The logic of scientific discovery is readily available. Enjoy some soothing reading, the first 25 pages will do. If it is not already in your possession – buy it! It may very well turn out to be your best investment ever.
One thing should be very clear however, and that is that: InterAcademy Council, United Nations and United Nations Climate panel IPCC have demonstrated a serious lack of knowledge within science, by: recommending, stating and accepting subjective statements in the form of qualitative level-of-understanding.
Have mercy with us!
If a scientific statement cannot be based upon any entity being utterly convinced of it´s truth, is it the possible at all to state a scientific statement? Oh yes – hang on – one of my coming posts might be about scientific statements.