Pournelle Comments on Global Warming

Jerry Pournelle comments on global warming in his 5 March View. Excerpting:

There's a lot more gas about Global Warming, but none of it causes me to change my view: yes, the Earth is warming, as apparently is the rest of the Solar System. The warming trend is hardly alarming: we have had warmer periods in historical times including the Medieval Warm Period. Yes, CO2 levels are rising, and since warm water holds less dissolved gas than cold water, any trend that warms the seas will accelerate that. The levels are high, but we don't really know the effect -- CO2 isn't a very efficient greenhouse gas. Water vapor is.

As the seas rise the surface areas become larger; this increases evaporation, which increases water vapor. Water vapor is a rather efficient greenhouse gas. Higher water vapor content usually means more clouds. Clouds are bright and tend to reflect received sunlight, reducing the insolation reaching the Earth. Models reflecting (no pun intended) this are in a very primitive stage and are not incorporated into the computer models that predict doom (doom now being 17 inches of sea level rise rather than Al Gore's 17 feet).

Enough clouds can produce cooling trends.

Ice ages are far more destructive than periods like the Medieval Warm (many say we should be so lucky as to get something like the Medieval Warm). The polar bears seem to have survived the Medieval Warm (proof: there are polar bears).