TC wrote:
>
> "I want to focus on West Antarctica, ......
> If this were to go, sea levels worldwide would go up 20 feet."
>
> For some reason many observers ignore the word "if".
After the last ice age ocean levels rose 150 meters with no help from
humans. There used to be a high-dry landbridge connected Siberia to
Alaska. That might be the way humans got to North America from Asia.
Bob Kolker