On Thu, 10 Dec 2009 03:57:22 -0800 (PST), Dawlish
wrote:

On Dec 10, 10:56Â*am, "I M @ good guy" wrote:
AGW has to be
based on more than the simplistic assumption
that CO2 increases causes temperature increases.

Obviously it is. CO2 increases will cause temperature increases
unless other (natural) factors override the increase which is being
caused by increasing CO2. The physics behind that was settled over a
century ago. Pumping more CO2 in the earth's atmosphere *will*
increase absorption of outgoing IR radiation and it will cause
warming. That is accepted by almost all climate scientists and
physicists and whether you like it, or not, it is. The greenhouse
effect is well understood and the physics behind it really are
settled. The degree of warming that will be caused caused by
increasing the atmospheric concentration of CO2 is also settled,
unless you wish to change those physical laws.


GHGs are what cool the atmosphere, and
all the scientists think the minor trace gas is
what warms the atmosphere?


That brings me to the point of my original post. Given that the
physics is settled, why isn't the earth cooler than it presently is,
given that two of the major natural varients (PDO and Solar output)
are in a state that ought to mean that they are having a negative
effect on temperatures - which they clearly aren't? They should be
causing cooling and we should not be experiencing some of the warmest
conditions in 130 years - unless the natural effects are *not*
managing to override the effects of CO2; which logically leaves CO2 as
the main driver of global temperature increase. Unless I (and also the
vast majority of climate scientists) see something else affecting
global temperatures in a greater way than the physics shows the
increases in CO2 should, I'm more likely to strengthen my views on CO2
being the cause of GW, than not.


Why isn't it cooler? Maybe if the methods
and weather stations used 50 years ago would
show more cooling, but if you are cock-sure,
no sense in exploring any possible explanations.