Weather and Climate

This site is not meant to repeat all the old (valid) arguments. (I do this in part, since it still seems necessary…) But I prefer to look at some interesting points in more detail. How is our weather working anyway? What do we know precisely (and how do we know it?) about the climate of the past? How are climate models working? I am looking at these points, more or less, as a layman. So in case you find mistakes – just tell me!