Friday, July 4, 2014


Scientific amateurs should beware of practitioners of string theory, as the often touchy creatures go abroad armed to the mathematical teeth, witness what befell code writer turned climate cintrarian David Evans.  The climate pseud has seen his pet It MustBe The Sun theory disemboweled by second-string string theorist Lubos Motl, whom he mistook for a political ally because the Czech libertarian is to the blogs of Prague what Fred Singer is to the Washington Times.

While WUWT's Moonie & moonbat chorus has touted Evans's 'Solar Notch Theory' as the best thing since Benthic Bacteria, Motl has reduced it to the last thing any denialist wants to see: an Integral!
Having run the numbers, Motl concludes Evans' much-touted solar correlations arise not from physics, but the self-referential convolution of his computer code:
"Simply because the integral equation above says that the temperature T(t) is the convolution of the response function R(t)and the total solar output P(t)If you know some basic calculus of Fourier transforms and convolutions, or if you're ready to check it using some verifiable identities for integrals, you will agree that the Fourier transform of the convolution is the product of Fourier transforms... That's great because the Evans response function in the frequency representation may be simply calculated as
R̃ (f)=T̃ (f)P̃ (f).
This frequency-based Evans response function is simply the ratio of the Fourier-transformed global mean temperature and the Fourier-transformed solar output!

Because the Fourier-transformed solar output has a peak (maximum) near the period 1/f of 11 years and because this Fourier transform appears in the denominator, R(f) will obviously have a similar minimum over there. The response function R̃ (f) will go close to zero for 1/f close to 11 years. It has to go to zero because it's needed to suppress the effect of the 11-year cycle that is seen in the sunspots and the TSI but that isn't seen in the global mean temperature!

I think that many of you will agree that the marketing point used as the title on Jo's blog

For the first time – a mysterious notch filter found in the climate
is pure demagogy."