Roy Spencer provides more “Evidence that Global Warming is a False Alarm: A Model Simulation of the last 40 Years of Deep Ocean Warming.”
Yes, in Hansen’s worldview he thinks he KNOWS with certainty what the climate sensitivity is, and that it is pretty high. In that case, for a given amount of warming, you can figure out the net forcing.
The trouble is that there has not been as much warming as expected for high climate sensitivity and the forcing from increasing CO2, so Hansen has to find some COOLING influence that he presumes in canceling out much of the CO2 warming.
His latest thing is claiming we are experiencing a delayed rebound effect from Pinatubo cooling. I find this very unconvincing.
These folks will go through all kinds of contortions to preserve their belief in high climate sensitivity, because without that, there is no global warming problem.
Cox and Stockwell reported on the same point here …
But Hansen does not question the magnitude of warming from CO2 despite recent measurements showing CO2 heating may be saturated. Indeed, the need to increase the cooling of aerosols comes about because the large positive forcing from CO2 is held constant.
… and another view here from Geoff Davies, e.g.:
It claims Hansen merely assumed the warming effect of greenhouse gases is known, when in fact Hansen has clearly spelt out the independent evidence for this.