Death of Global Warming, Part 3

Myth #5: CO₂ is such a weak greenhouse gas that it cannot be the cause of the observed warming.

Another straw man. Most people aren't arguing that it can't be, they're arguing that it isn't or that it is a result, etc.

CO2 has increased from 366.65 (1998) to around 393 (today). Using one of the IPCC forcing equations:

Forcing in w/m2 = 5.35*ln(393/366.65) = .37 w/m2

This is good for about 0.1 degrees Celsius. Has the climate warmed 0.1 degrees in the last 13 years?

Courtesy of www.climate4you.com is the UAH temperature anomaly graph.

If you follow the link to the graph you get the feeling we are 0.3 degrees cooler, despite a 7% increase in CO2. This isn't much evidence of CO2 forcing.

The temperature anomaly is somewhere between 0 and .6 degrees Celsius. The CO2 level has gone up 113 ppm. This should have caused a forcing (using the above equation) of 1.8 w/m2 or 0.33 degrees Celcius.

Given that the .6 estimate includes IHI effects, data maturity changes, etc. the actual value is somewhere between 0 and 0.6. 0.3 or 0.4 would be good choices. This would mean that the IPCC estimates of CO2 forcing are correct but the predictions of 5x water vapor forcing are not, the net feedback is approximately zero.

Since fossil fuels are responsible for 30% of the CO2 increase the temperature rise due to fossil fuels is 0.1 degrees C.

Bottom line - CO2 has an effect and causes some of the warming, not a worrisome amount, but some.

Myth #6: CO₂ concentrations are not correlated with global temperature due to periods in the geologic history when CO₂ was higher and the planet was in an ice age.

This myth is deceptive - the CO2 concentrations do generally correlate with temperature - in that rising temperatures cause a delayed increase in CO2.

The author does a lot of dancing about late Ordovecian period when there was an ice age with CO2 levels 14x the current levels. Given that the historic CO2 increases trail warming by centuries, historically temperature drives CO2. Claiming that historically CO2 drove temperature is simply deceitfully. The cause has to precede the effect. Also there is published literature to the effect that CO2 has to be below 600 ppm to have a ice age. The historic record has exceptions that make this look a little dubious (14x is a lot more than 600ppm).

So the myth is generally untrue - but only because temperature drives CO2 levels.