I’ve studied this quite a bit. My conclusions:
1. The world is warming at about the same rate as in past periods of history, including periods where humans were not producing C02.
2. There is no demonstrable causation between human generated C02 and the current 250 year long warming trend.
3. The ability of C02 to cause warming is minimal. The concept of anthropogenic Global Warming is that CO2 warms things a little, which then generates more water vapor, which warms things a lot. So far, this effect has only been demonstrated on a global scale inside computer generated simulations. In other words, no hard evidence.
This link, and follow up letter in the WSJ on Feb 21, give a sense for how “settled” the science is:
http://online.wsj.com/article/SB10001424052970204301404577171531838421366.html
Here’s the follow up:
http://online.wsj.com/article/SB10001424052970203646004577213244084429540.html
I’ve studied this quite a bit. My conclusions:
1. The world is warming at about the same rate as in past periods of history, including periods where humans were not producing C02.
2. There is no demonstrable causation between human generated C02 and the current 250 year long warming trend.
3. The ability of C02 to cause warming is minimal. The concept of anthropogenic Global Warming is that CO2 warms things a little, which then generates more water vapor, which warms things a lot. So far, this effect has only been demonstrated on a global scale inside computer generated simulations. In other words, no hard evidence.