As you say, much of your points are personal judgments. I do want to respond to some that aren't:
"2. We're still well within the bounds of normal, habitable historical temperatures."
This is a severe oversimplification, IMHO. Human society is sensitive not just to whether the Earth is overall habitable, but to impacts to the significant "sunk costs" we have in the locations of population centers. It's not much comfort to the people of California if the Earth remains habitable on average when the Sierra snowmelt disappears and the state faces a drought of unprecedented proportions.
"4. Carbon dioxide currently makes up 0.3% of the greenhouse gases including water vapor, and about 5% of the non-water vapor greenhouse gases. Carbon dioxide increases are lagging temperature increases - suggesting that CO2 is not the biggest culprit of global warming."
Where do you get that CO2 is 0.3% of greenhouse gases? It's true that water vapor is the largest contributor to the greenhouse effect, but CO2 is next. It accounts for 50% of the non-water greenhouse gases and for way more than 0.3% of the total greenhouse effect. Besides, counting water is a little spurious because the water content of the atmosphere is set by the temperature. Thus, if temperature goes up, water content goes up. So saying that CO2 doesn't matter because water vapor is much more important is wrong, it's precisely the opposite. CO2 matters more because its effect is amplified by water. (Barring controversies about cloud covers.)
CO2 is also the greenhouse gas that has the longest lifetime in the atmosphere. The others (methane, etc) break down a lot quicker.
> It's not much comfort to the people of California if the Earth remains habitable on average when the Sierra snowmelt disappears and the state faces a drought of unprecedented proportions.
It's a really long discussion, but our ability to locally adapt to climate change is actually quite good and improving regularly. Temperatures are rising really, really slowly - you can get the 2-3 degrees per 100 years back by planting trees and irrigating. Desalination has come along incredibly fast too. I can go into greater detail if you have specific questions, I know a fair bit about this stuff.
> Where do you get that CO2 is 0.3% of greenhouse gases?
"Carbon dioxide (chemical formula CO2) is a chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom. It is a gas at standard temperature and pressure and exists in Earth's atmosphere in this state. CO2 is a trace gas being only 0.038% of the atmosphere."
"2. We're still well within the bounds of normal, habitable historical temperatures."
This is a severe oversimplification, IMHO. Human society is sensitive not just to whether the Earth is overall habitable, but to impacts to the significant "sunk costs" we have in the locations of population centers. It's not much comfort to the people of California if the Earth remains habitable on average when the Sierra snowmelt disappears and the state faces a drought of unprecedented proportions.
"4. Carbon dioxide currently makes up 0.3% of the greenhouse gases including water vapor, and about 5% of the non-water vapor greenhouse gases. Carbon dioxide increases are lagging temperature increases - suggesting that CO2 is not the biggest culprit of global warming."
Where do you get that CO2 is 0.3% of greenhouse gases? It's true that water vapor is the largest contributor to the greenhouse effect, but CO2 is next. It accounts for 50% of the non-water greenhouse gases and for way more than 0.3% of the total greenhouse effect. Besides, counting water is a little spurious because the water content of the atmosphere is set by the temperature. Thus, if temperature goes up, water content goes up. So saying that CO2 doesn't matter because water vapor is much more important is wrong, it's precisely the opposite. CO2 matters more because its effect is amplified by water. (Barring controversies about cloud covers.)
CO2 is also the greenhouse gas that has the longest lifetime in the atmosphere. The others (methane, etc) break down a lot quicker.