In business communications training, we were taught to think about the “elevator version” of the point we were trying to make. If we were on an elevator alone with the CEO and had 30-seconds to make our pitch, what would we say.
Richard Lindzen, in his presentation at the Heartland Conference, has the best short (100-ish word) summary of the core of many skeptics’ concerns with catastrophic AGW theory that I have seen for a while:
Here are two statements that are completely agreed on by the IPCC. It is crucial to be aware of these facts and of their implications.
- A doubling of CO2, by itself, contributes only about 1C to greenhouse warming. All models project more warming, because, within models, there are positive feedbacks from water vapor and clouds, and these feedbacks are considered by the IPCC to be uncertain.
- If one assumes all warming over the past century is due to anthropogenic greenhouse forcing, then the derived sensitivity of the climate to a doubling of CO2is less than 1C. The higher sensitivity of existing models is made consistent with observed warming by invoking unknown additional negative forcings from aerosols and solar variability as arbitrary adjustments.
These concerns form the core of my most recent video.