Earlier quoted context omitted.
It's not meant as a perfect analogy for global warming, but rather an illustration of how a constant state isn't necessary for something to be said to be "changing", which was OP's claim.
The goalposts are that way --->
My apologies, internet stranger, for thinking I had different goals than the ones you so cleverly picked up on in my one paragraph comment. Clearly you were more correct about my goals than I was.