As any financial analyst knows, fools and their tools can find confirmation for any pet theory. The only route to certitude is falsification.
Realclimate shows numerous examples of confirmation bias in their recent article. In particular, gavin dicusses an update to Hansen’s famous graph of projections made back in 1984.
They ‘confirm’ that scenario B — increasing CO2 — matches current trends.
The trends are probably most useful to think about, and for the period 1984 to 2009 (the 1984 date chosen because that is when these projections started), scenario B has a trend of 0.26+/-0.05 ÂºC/dec (95% uncertainties, no correction for auto-correlation).
Scenario C — no increase in CO2 — is more consistent with the temperature increase. A statistical test of the alternate hypothesis Ha, rejecting the view that observed temperature differs from the no increase in CO2 scenario, provides support for the view that CO2 is irrelevant.
Quasi-scientists have one thing in common with scam artists, emphasis on confirmation and ignoring contradictory evidence. Note the RealClimate article fails to mention scenario C at all in their post. See ClimateAudit for details of the scenarios and updates.
As an example of testing the AGW hypothesis, I was sent this analysis done by George White. I don’t know anything about George, but he obviously understands the issue of falsification, and has a strong physical science background.
He tests a number of hypothesies of AGW:
- a 20% increase in CO2 is expected to cause an increase in the average global temperature of about 0.8Â°C,
- claims that the Earth takes decades to respond to forcing changes, and
- a small amount of additional forcing from increased anthropogenic CO2 is amplified by a climate system dominated by strong net positive feedback from water vapor.
The analysis of the satellite data shows conclusively that every prediction of the AGW hypothesis that can be tested by quantifying the energy balance fails. It only takes one failed test to disprove a hypothesis, and here we have many. The only possible conclusion is that the climate forcing effects of anthropogenic CO2 are far smaller than the AGW communities consensus value. In fact, it’s so small, that it’s certain that the trillions of dollars we are poised to spend on CO2 mitigation will have no effect, other than to drag down the worlds economy and impede the goal of energy independence.