[tossaway322]

gjm11 says: "Is there some special bad thing that happens once 410ppm is reached, that's qualitatively different from 400ppm?"

Yes. Climate change proponents post articles such as the OP here and then cry "The sky is falling, the sky is falling and I can prove it! We're at the 410 PPM Threshold, just as we predicted!"

[mtempleton]

You're being downvoted, but dissenting opinions should be allowed, even when it comes to climate change. There is a reasonable argument to be made that climate change alarmism is not productive. I saw Bill Nye answer the question of 'what happens due to global warming,' to which he replied, 'people's qualities of life will most likely go down because people will fight over resources,' that said, right now we have a surplus of resources in a very real sense. We already basically have productive capacity to feed every person on earth, but it's politics and greed that makes people starve, not resources.

Whether the down-voters like it or not, climate change is a very real and scientifically established fact, but what that will do to people on the world is not a scientific fact. It's just what currently most people predict will happen (and disagreeing with this is feels like some kind of thought crime in the traditional sense--it's not science). The world is not going to end. Biodiversity and Biomass is decreasing. The Northwest Passage is being opened up. Iron fertilization will become a more likely policy to sequester carbon and increase biomass in the oceans. Sea levels will rise. Extreme weather patterns most likely will increase. Productive farm land may or may not increase. Russia actually may have a fair bit to gain from it. But the fact is, there is a lot we really don't know.

In the very long run our civilization will need to harvest as much energy from the sun as possible, but in the meantime we've done a pretty fantastic job of screwing up the planet, so it's a pretty good idea to stop emitting so much pollutants into our atmosphere, since we don't really know for sure, but we have a lot of reasons to think it won't be good. That's really the best argument to end climate change, but it's probably not convincing enough to change behavior in large numbers of people.

That said, the politics and bureaucracies around climate change have started to resemble the War on Poverty and War on Drugs--institutions which now exhibit bureaucratic intertia (have an inherent perverse incentive structure, and they rationally (evilly) place their own survival over that of solving the problems they're tasked with).