Awblain
Look at those variations though, and consider their nature.
There is no need. You said:
there isn't any "variable gravity" until you're worried about altitudes that reach tens or hundreds of km high.
Which is an opinion shown to be false by that link to NASA I provided. I am not going to enter into a game of semantics with you because I find that sort of debate really lame.
If you wish to prove the point you have now shifted to:
If the author is including GRACE maps is his fluttering debris data, then he's missing the wood for the trees.
Is he using pressure altitude to start his simulation? If so, then he should have a further think about the "variable gravity" bit and where isobars lie in 3D.
Then please do get on with it, it might be interesting
