This might be opening a can of worms, but "electing national leaders who know that Global Warming is actually happening" can go a long way.

Now, in some cases, I understand that the alternative (because there's usually the alternative) candidate is so unpalatable to you because of their other political positions.

I'm just saying that, if we're serious about this, we must rate "Does this candidate understand that Global Warming is real?" as a "Very Important Factor"(TM) in choosing your representatives. At all levels of the government.