They don't have to be funny. They just need to provoke thought in people like any other witty writ about the situation at hand.

They don't appeal to the people who don't believe, and just confirm the beliefs of people who do.

They're not even using that to good effect.

There's no, "Illustrated guide to not being part of the problem." There's no, "Doing this might actually help!"

There's only, "Oil company bad!" and, "ZOMG, those poor animals!" and "Politicians don't care about the planet!" Just pandering.

They're free to make comics about whatever, but don't pretend they're actually tackling climate change.