Besides Per there is another character named Plum (I kid you not) who is trying to fit cycles in the temperature and claims to use 89 (!) sinusoidal factors. All these are arbitrary apparently. Problem is that one can fit just about anything with that many factors. That's over at Clive Best's blog if you want to check it out.

Whether Per is something something similar here, I don't know. The problem with Per is that he is intentionally being obtuse on what he is doing. He first posted here probably over a year ago, and he still hasn't given any details. I do marvel at his fit above -- eyeballing it, I wouldn't be surprised if his correlation coefficient is at least 0.995. Rare to find anything that good considering all the uncertainty involved.

All I know is that we won't get anywhere unless we deal in good faith and are able to share AND reproduce scientific results.