This post point out just how many oscillators there are in the climate system. I don’t think that the post got all of them as there are some local ones and the ocean oscillators such as the PDO. The real problem is that for a computer model to take all these into account you would first have to know some baseline temp and inputs to get the coefficients to get updated temps to get new coefficients and so on and so on. If you have large temp differences you can wing the approximations and keep the computer time from being completely insane. When you are dealing with the atmosphere and low delta T’s and energy transfers you are sitting right in the margins of errors. Use bad approximations and coefficients and you model is going to be garbage.

More from Watts up with that.

http://wattsupwiththat.com/2015/09/17/how-reliable-are-the-climate-models/