WHY does aeration raise ph?

I understand that aeration, by itself, raises ph but don't know WHY?

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Vaguely and loosely, it's like knocking carbonation out of soda, which makes it flat but less acid. It's actually carbonic acid molecules, I believe, that get converted.

Aeration increases the rate of carbon dioxide outgassing from the water. Removing carbon dioxide from water is effectively the same as removing carbonic acid (which is a combination of carbon dioxide and water) and removing an acid raises the pH.

Pool water is intentionally over-carbonated in order to provide a pH buffer and along with CH to saturate the water with calcium carbonate to protect plaster surfaces.

Or beer going flat....I'm told that happens but mine never lasts long enough to find out.
Anywho, thanks guys. I need to do what to do but sometimes it helps to know why I'm doing it.