Climate Change Conversation Aborted

Published April 23, 2013

An  editorial essay by American Chemical Society (ACS) officers Bassam Shakhashiri and Jerry Bell  (Science 5 April 2013) extends a gracious invitation for a “respectful  conversation” about Climate Change.  Yet when I tried to respond, the  editors of Science refused to print it.  So much for “conversation.”

Aside  from its admirable tone, the editorial itself is a mixture of things that are  trivially true (i.e., that the climate is changing – indeed it does  so, on  all time scales, and is likely to continue) to statements contradicted by  readily available evidence (that there has been an increase in weather extremes  over the past century — contrary  to published official statistics).   In between, one finds assertions that are still under intense scientific  debate.

It  is true, unfortunately, that many professional societies, including also the  ACS, have issued hastily drawn climate statements, espousing an alarmist view  that even exceeds that of the IPCC.  In this, they have been joined by many  national academies, including the US National Academy of Sciences and the  venerable Royal Society.  But they all simply regurgitate the shaky  conclusions of the UN-IPCC (Intergovernmental Panel on Climate Change) —  without adding any original analysis.  A notable exception to this  lemming-like procession is set by the Chinese Academy of Sciences, which has  translated and published the voluminous reports of the NIPCC (Non-governmental  International Panel on Climate Change) and even organized a Workshop to discuss  its conclusions, which contrast starkly with those of the  IPCC.

As  an example of ongoing debate: Is the climate really warming, as claimed in the  editorial?  Hard to tell unless one specifies the time interval.   Nearly everyone agrees that the climate is warmer now than during the Little Ice  Age (as recently as 200 years ago).  Some believe that most of the warming  occurred before 1940.  Increasingly, many accept that there has been no  observed warming for at least the past decade.  The situation between 1940  and 2000 is somewhat murky; it all depends on which data set one accepts as  truly representing global climate.  The ongoing debate on this issue will  determine the answer to the key question: How important is the human  contribution to climate change?

Many  of us find evidence for anthropogenic global warming (AGW) unconvincing.   The report of the UN science panel [IPCC 2007] bases it mainly on comparing a  single (uncertain) observed temperature set with one calculated from (incomplete  and non-validated) climate models driven by (anthropogenic) increases in  greenhouse gases, like carbon dioxide.

Even  less convincing are earlier IPCC [2001] claims that the 20th century  has experienced unusual warming compared to preceding centuries (the so-called  ‘Hockeystick’ curve).  A recent paper in Science (8 March 2013)  has tried to resurrect this particular bit of fiction. [See Another  Hockeystick?] But with intense scrutiny after its publication  (following the obligatory peer review), the authors now admit that this result  is no longer “robust.”  There have been many such papers published in  prestigious journals in the past 25 years that have all claimed sure proof of  AGW — or implied it; it would be good to see them corrected or formally  withdrawn.

So  what is causing the climate to change — on a human time scale, of decades to  centuries?  The jury is still out on that particular debate; but  increasingly the evidence points to the Sun — and to changes in solar  activity.  The Science editorial concludes that “reducing  emissions [of CO2] is required to avoid a warmer planet.”   It would  be well to settle the crucial question of the cause before undertaking costly  projects to mitigate climate  change.  Some of these projects – like cellulosic ethanol or ‘carbon  capture and sequestration’ — have not even been demonstrated on a commercial  scale.  Good advice would be to “Look before you Leap.”

[First Published at American Thinker]