Our Arbitrary Rulers

clipped from ker-plunk.blogspot.com The modellers just assume relative humidity is also constant while CO2 concentrations change. There is no physics in support of this assumption, and no way to calculate its value from first principles. This assumption means that if temperatures increase for any reason, the amount of water vapour in the atmosphere increases. But water vapor is the most important greenhouse gas, so the GHE becomes stronger and temperatures increase more. The current theory does not determine this - it is only an assumption. If this assumption is only slightly wrong, it completely changes the expected response of increasing CO2 because water vapour is such a dominant greenhouse gas. The assumption, that relative humidity is constant when CO2 concentrations increase, is completely absurd. This violates fundamental energy conservation laws. So it makes no sense to assign an arbitrary rule for one of the greenhouse gases.