In 2007 the American Physical Society leant its august weight to the consensus thus …
The evidence is incontrovertible: Global warming is occurring.
If no mitigating actions are taken, significant disruptions in the Earth’s physical and ecological systems, social systems, security and human health are likely to occur. We must reduce emissions of greenhouse gases beginning now.
Some of its members were less than impressed. 160 members of the APS protested. Some prominent scientists like Nobel Prize winning Ivar Gievar (“Incontrovertible is not a scientific word. Nothing is incontrovertible in science“) and long-standing Professor Hal Lewis (” … the global warming scam, with the (literally) trillions of dollars driving it, that has corrupted so many scientists, and has carried APS before it like a rogue wave. It is the greatest and most successful pseudoscientific fraud I have seen in my long life as a physicist“) resigned.
Under the APS rules such policy statements must be reviewed each half-decade. The review is underway. Perhaps with one eye on its membership and the other on the lookout for more climategates or Himalayan glaciers melting at impossible rates, the committee that it has set up is remarkably balanced, three climate modellers and three skeptical scientists. The proceedings are fairly transparent for instance the Workshop Framing Document can be read <HERE>.
It raises some excellent questions. For a moderately lengthy discussion read Tony Thomas.
A sample …
While the Global Mean Surface Temperature (GMST) rose strongly from 1980-98, it has shown no significant rise for the past 15 years…[The APS notes that neither the 4th nor 5th IPCC report modeling suggested any stasis would occur, and then asks] …
To what would you attribute the stasis?
If non-anthropogenic influences are strong enough to counteract the expected effects of increased CO2, why wouldn’t they be strong enough to sometimes enhance warming trends, and in so doing lead to an over-estimate of CO2 influence?
What are the implications of this stasis for confidence in the models and their projections?
What do you see as the likelihood of solar influences beyond TSI (total solar irradiance)? Is it coincidence that the stasis has occurred during the weakest solar cycle (ie sunspot activity) in about a century?
Some have suggested that the ‘missing heat’ is going into the deep ocean…
Are deep ocean observations sufficient in coverage and precision to bear on this hypothesis quantitatively?
Why would the heat sequestration have ‘turned on’ at the turn of this century?
What could make it ‘turn off’ and when might that occur?
Is there any mechanism that would allow the added heat in the deep ocean to reappear in the atmosphere?
IPCC suggests that the stasis can be attributed in part to ‘internal variability’. Yet climate models imply that a 15-year stasis is very rare and models cannot reproduce the observed Global Mean Surface Temperature even with the observed radiative forcing.
What is the definition of ‘internal variability’? Is it poorly defined initial conditions in the models or an intrinsically chaotic nature of the climate system? If the latter, what features of the climate system ARE predictable?
How would the models underestimate of internal variability impact detection and attribution?
How long must the stasis persist before there would be a firm declaration of a problem with the models? If that occurs, would the fix entail: A retuning of model parameters? A modification of ocean conditions? A re-examination of fundamental assumptions?
Searching questions are also posed regarding climate sensitivity, climate modelling, the unexpected increase in Antarctic sea ice and the scale of anthropogenic forcing.
The questions are excellent but it’s how they are answered that matters. If the APS finds that the science is not settled, that observations do not match the model projections, that the evidence is not incontrovertible then their support for the AGW hypothesis must be withdrawn. In that case they will be the first significant scientific body to step back onto the path of science.
It will then be safe for the flat earthers, headless chickens and climate deniers to come out of hiding without fear of being tried for criminal negligence.