GLOBAL CLIMATE CHANGE: American Physical Society Change of Heart

Physical Society Backs Down (sort of) on its Climate-Change Policy Statement



After posting a controversial national-policy global-warming statement in 2007, the American Physical Society has had to modify its position — something that took three years to come about, and only now because of membership insurrection.

In part of its concession, the APS downgraded its confidence about ongoing global-warming from “incontrovertible” to merely “compelling.”

In another concession, the organization finally admitted that there was “uncertainty” in predictions about the cause of global-climate change.

It also belatedly acknowledged that some important published trends do not stand by themselves, but are dependent on temperatures and other data referenced (normalized) back to the year 1750.

Regrettably, APS publications have downplayed the April 2010 revisions as though nothing was changed, when actually the Society appended major concessions to their original policy statement.

In any event, nothing in either APS statement helps determine whether humans are responsible for, or have the capability to significantly modify global climate trends.

In 2007, the American Physical Society approved a “National Policy” climate-change declaration
subsequently criticized by many of its membership. In response to the protest, the APS in April 2010 added a “Climate Change Commentary” that contained transformative revisions and clarifications.
The original policy statement about global warming highlighted the term “incontrovertible,” accompanied
by vague, unconstrained context. The newly adopted “Commentary” advises that the Society now officially considers evidence for global temperature rise over the last century to be “compelling.” Although the original declaration wasn’t invalidated, the new Commentary effectively narrows and revises its 2007
statement. Going from the widely quoted (and contested) term “incontrovertible” — to merely “compelling” — is a significant, though reluctant and welcome concession to the protesters regarding certitude in the scientific evidence.  In other words, the data as interpreted has some uncertainties.
Notwithstanding this concession, the aggregate APS policy still underplays current statistical uncertainty
in regard to anthropogenic-driven effects, that is: What role has human activity played, and what can
humans do about in a cost-effective manner? 
The revised statement still offers nothing more than a cheerleading exhortation to do something out of fear, rather than by scientific consensus. It offers nothing, even qualitative, about economic costs and material benefits. While there is considerable scientific concern and  recognition of global climate change, no consensus exists, certainly not incontrovertible, among scientists — especially with regard to the efficacy of proposed remedial actions.
The new official statement contains concessions and clarifications (whitewashed on the website as a
“Commentary” rather than a revision). You can see for yourself, by comparing statements, that the APS did in fact make significant revisions.
The Commentary contain two notable and critical modifiers, not previously stated, but now exhibited
more than once:

  • It directly makes note of “uncertainties,” “uncertainty in the estimates,” “uncertainty in net effect,” “probability distributions,” and other qualifying terms that physicists who are experienced in scientific methodology find to be de rigueur, yet entirely omitted from the original American Physical Society statement.
  • It stipulates that data found in the international panel climate-change (IPCC) formulation is “relative to its pre-industrial value” and “relative to their pre-industrial values.” This is an indirect, albeit belated admission that radiative-forcing data in the 2007 IPCC report were normalized to the year 1750, a arbitrary constraining factor understated in the 2007 compendium and usually omitted in derivative analysis. In other words, lacking definitive measurements prior to the industrial revolution, the IPCC did as well as it could in normalizing available data. One problem is that the IPCC understated its data adjustment, possibly to the point of obfuscation. Another problem is that global temperatures in 1750 were comparatively low, thus rendering subsequent values markedly higher.
While there is considerable and demonstrable statistical confidence that aggregate contemporary global
warming has occurred (at least before the 21st century), there is much less proven causative connection with historic human activity and even less demonstration of statistically confident, cost-effective remedial

action. In light of worldwide economic demands, societal needs would be better addressed, in my opinion, on the basis of more substantive science.
The APS national policy declaration was revised in a roundabout way, and then only as a result of several
years of membership protest. As one of those who submitted recommendations for revision, I applaud the
Although changes in climate are obvious, it’s not yet clear whether humans are significantly responsible.
A justifiable assessment needs to be couched in probabilistic terms, in a manner consistent with accepted
scientific methodology.
After all, there is evidence that global average temperature in the last dozen years had leveled off —
consistent with a reduction in cyclic sunspot activity.
For more on this topic, please see my Knol GLOBAL CLIMATE CHANGE (Revision 1), and for more
on the scientific method, see NUCLEAR EXPERTISE: Role of Statistics in Forensic Science.
The new and old official APS “National Policy” pronouncements are posted on the Policy and
Advocacy section of their website (
Incidentally, before retiring after 41 years at a national nuclear laboratory as a PhD physicist, I had
significant experience and publications in the science of measurements, and I was elected by my peers as
a “Fellow” of the American Physical Society.
Just so nobody thinks I am imagining the somewhat concerted (and disconcerting) effort to downplay the revisions, kindly take note of the following:
(1) Here’s the lead paragraph of an internet article, “APS Council Rejects Bid to Soften Society
Statement on Global Warming” posted even before the APS statement was formalized:

The Council of the American Physical Society has overwhelmingly rejected a proposal to

replace the Society’s 2007 Statement on Climate Change with a version that raised doubts about global warming…. Its recommendations were to retain the existing statement, and to review the statement for its “clarity and tone.” That happened on [8 Nov. 2009]. (Eli Kintisch %5B10 Nov. 2009]).

(2) The 10 May 2010 APS News supplied a lead article “Council Passes Addendum to Climate
Change Statement.” Its tone and content would have been better titled “Council Recognizes Flaws in
[2007 APS] Climate Change Statement.” The news article glosses over substance, particularly POPA’s
concessions and clarifications, while highlighting procedural and scripting changes.
(3) The new APS “Climate Change Commentary,” adopted 18 April 2010, pretends that are no transformative revisions, clarifications, or omissions. It is whitewashed as a “Commentary” rather than
admitting that it is a revision.
(4)  In the course of time, by means of articles or letters to Physics & Society (rejected), Science (rejected), Physics Today (rejected), and just recently, APS News (submitted), I have pressed for inclusion of these two caveats about probabilistic conditioning and normalization.  
(5) It is gratifying to see that the APS Council has seen fit to include these unattributed two points within its “Commentary.”  Just because the APS concession closely maps my suggested clarification — submitted directly in response to their call to membership —  is hardly proof of cause-and-effect, but it is consoling to see these two points adopted as I have advised.
(6) I did manage to get these two key points published as a Letter in a local newspaper, “Contradictions about global warming,” in the North County [California] Times (16 Oct. 2009).
(7) Thanks to the on-line facilities offered by Google in the form of “Knols,” such as this one, I had posted a comprehensive treatment under the title “GLOBAL CLIMATE CHANGE: Statistical Expectations and Humanistic Perspective”  It’s original version was published in 2009, and Revision 1 was last edited at the end of that year.  In regard to limitations in the 2007 IPCC report, the 2009 Knol provides details about data normalization, limitations of data normalization, radiative-forcing inferences, the U.S. Supreme Court “Daubert” standard for scientific testimony, and IPCC limitations not fully and candidly disclosed.  In addition to addressing scientific concerns about IPCC data normalization, the Knol draws conclusions about global-warming trends and about the need for humanistic balance in scientific decision making.  The Daubert standard is separately addressed in at least two other Knols.
(8) I have benefited from the introspective and orthogonal studies initiated by my former Argonne colleagues, Jerry Marsh and George Stanford, who have independently reviewed, critiqued, and reported the science underlying interpretation of global-climate change phenomena.
In summary, regardless of word-smithing and press-management, it is evident that the Society’s national policy declaration on global-climate change was revised and improved, but only as a result of several years of vocal membership protest.