As an earth scientist, can I just say how relieved I was that his talk was so great? It isn't that climate science is complicated, it's just that having celebrities give science-based talks makes me nervous. Some of them, well intentioned though they may be, fall for ideas like vaccines causing autism and then use their star power to get large numbers of people to believe.
But Harrison Ford gave a great talk with no cringy numbers or claims that I detected, and he put it all in such great human terms. It's a shame it has to come from a celebrity to get our attention, but if that's the way it needs to be, then I'm all for Harrison Ford as one of the earth's leading spokesmen.