by Roy W. Spencer, Ph. D.
[Ed. Dr. Roy Spencer wrote a post (22 March 2018) disagreeing with Lord Monckton’s theory that climate scientists have over-estimated feedback by a factor of 2, because they have been using the feedback equations incorrectly. Dr. Spencer agrees with the factor of 2 error, but he disagrees with the reason given by Lord Monckton. In response, Lord Monckton has countered Dr. Spencer’s argument with a post of his own on Spencer’s blog. The original Spencer post can be found here with Lord Monckton’s counter argument here.]
A recent article by Lord Christopher Monckton over at WUWT argues that there has been an “elementary error of physics” that has led to climate sensitivity being overestimated by about a factor of 2.
I agree with the conclusion but not the reason why. It is already known from the work of Otto et al. (2013), Lewis & Curry (2015) and others that the climate system (including the deep oceans) has warmed by an amount that suggests a climate sensitivity only about half of what the models produce (AR5 models warm by an average of 3.4 deg. C in response to a doubling of CO2).
But the potential reasons why are many, and as far as I can tell not dependent upon Christopher’s arguments. For those who don’t know, Lord Monckton is a pretty talented mathematician. However, like others I have encountered over the years, I believe he errs in his assumptions about how the climate research community uses — and does or does not depend upon — the concept of feedback in climate modeling. Continue reading “Climate F-Words”