Firstly, I am not here as a total climate denier but do question the motives and agendas of those involved in the process of CO2 reduction. It is all reminiscent to me of watching the various bureaucracies try to solve the fisheries issues. Lots of dollars spent and lots of studies done but in the end nothing has changed, at least not much.
I would welcome some criticism of the following presentation:
Well, ok, here is some criticism of that video, and I will follow it with something more constructive.
You've posted two videos. Doubtless I'm missing details, but, my impression is one of them is basically claiming observed warming trends are due to non-human exotic solar effects, the other is saying, in the criticism of Hansen, there is no warming trend. Well these are mutually contradictory positions. They could both be wrong, but they certainly can't both be right. If it were me, I'd be thinking, at least one of these sources isn't credible. And I would be looking for some more credible source that (a) wasn't grinding a political axe at the same time and (b) wasn't on YouTube. For example -- David Archer at U. Chicago has a wealth of good materials designed for people who are not science majors (for science majors there are more in-depth introductory treatments). Lots of others by working scientists, Isaac Held's blog, RealClimate, to name a couple. I challenge you to spend some time with such materials, and then come back and look at these same videos again.
At one time we used to talk about the toxic chemicals-- agricultural and industrial and pharmaceutical that somehow find their way to our soil, our waters, our air, and our bodies. And let's not forget plastics. What happened to outrage over these pollutants? Now CO2 seems to be the most villainous. How did that happen? Perhaps there is no big money in these now "minor" pollutants. We have members of Congress telling us we have 12 years before the end of the world if we do not act now. Makes it hard to take some people serious and makes one question all sources of information.
What's your point exactly? I hardly think concern over various other toxicity issues has gone away -- witness the recent kerfluffle over chlorpyrifos. But yes, CO2 is different for a bunch of reasons. For one CO2 emission is integrated into the world economy in a way few other things are. More critically, I can't really think of anything else that has the unique combination of persistence and damage potential. This is something the mass media generally has done a truly awful job of communicating, though, in all fairness, it's a more subtle thing than can't be discussed in a few soundbites. In a nutshell here is why CO2 emissions are such a concern:
1. Once a slug of CO2 is put into the atmosphere, a certain amount of the bump in CO2 concentrations, as well as the associated impacts, are there for what is basically forever on human timescales. This is not like, to give one example, the ozone hole crisis of a generation ago, where once emissions ceased, the damage would be expected to repair on a tolerable timeframe. Because of this, for any given level of warming, there is a set TOTAL emissions budget that can be calculated (or at least estimated). Total means the sum of all emissions over all past time. Blow past that, you blow past the target temperature rise. Where these 10-20 year number come from is taking as the temperature target some rough consensus from scientists about the boundary between unpleasant and catastrophic, getting a CO2 budget from that target, subtracting off what has already been emitted, looking at current emissions rates, and then making a guess at the rate of emissions reduction that might be both technologically and economically/politically feasible. There is a lot of variance in the numbers, but pretty much any realistic estimate comes to the conclusion that avoiding very severe impacts requires steep emissions drops very soon, decade or two timescale, probably sooner than is politically feasible, and only borderline technologically feasible.
2. Unlimited CO2 emissions comes with a risk of damage that at the high end is hard to find a parallel to. This is also something the media does an awful job in communicating. For one, the scientific community hems and haws, as the high-end scenarios are by definition improbable and uncertain, and scientists generally are averse to be seen as fearmongering. For two, the worst case type scenarios are so far removed from people's personal experience that they aren't considered believable/credible. You're using 'end of the world' as hyperbole, but I can give you some things to read that, if you are really as open minded as you say, will have you reconsider if that is such a joke.