You'll get cranks and opponents on everything. The real problem is the overwhelming majority of people who think "OK, sure, bad stuff is happening, but what impact do my simple efforts make to improve it? Meh."

Platitudes about how the world will be destroyed will not sway those people to act en masse - there needs to be some other element to it, but what? (I personally lean towards the eventual technological solutions, since technology has dug us out of many a hole before.)

I do broadly think that only a technological or government-driven solution is viable, however, because unless everyone does something significant, the needle won't move, and everyone won't do something significant without being forced or radically assisted.

So, let's get out of our technology bubble, away from keyboard, and let's go do something.

Please don’t. Consider that your audience is not a vocal minority (you can pretty much ignore them), but silent majority. Majority of Americans actually believe in man-made climate change (google gallup polls), they just don’t have it at the top of their priority list.

convince people to stop using their IPhones, stop using your PC, stop driving cars, stop using electricity. Bam, problem solved. Or try to overthrow corporations with big carbon monoxide signatures. Yeah, I didn't think so.

It is an immensely complex problem that has no easy solution, and people talking about it is not gonna do much, or is it??

Step 1: Assign a cost for CO2 emissions.

Step 2: Let the market deal with the costs.

Step 3: Asses if the cost was at the right amount. Adjust if necessary and repeat.

If you don't believe in Capitalism:

Step 1: Change the governmental system to a system of your liking.

Step 2: Find a way in this new system to control what companies do. e.g. state planned economics, regulations, etc.