Chronology Current Month Current Thread Current Date
[Year List] [Month List (current year)] [Date Index] [Thread Index] [Thread Prev] [Thread Next] [Date Prev] [Date Next]

Re: [Phys-l] Prof. Hal Lewis resigns from APS

Bill Robertson wrote:

A question regarding the warming of late. We are on a warming trend in
the ice core data, and we are not significantly off that graph in
temperature (although way off the graph in CO2). Is the recent (100
years) warming obviously different from what one would expect anyway
from the natural cycles? If so, how do we know that? Any resources
come to mind?

In a word, no. I could google for something, but so can you. But I wonder, since you don't comment on it, are you saying that you find my summary (below) not to be at least a little bit compelling? If so, why?

John Mallinckrodt
Cal Poly Pomona

John Mallinckrodt wrote:

1. CO2 levels in the atmosphere are higher by at least 30% or so
than we have seen in at least a million years and that rise (over
the last hundred or so years) is very clearly due to human activity.

2. CO2 is a greenhouse gas with very well known radiative forcing
potential and predictions can be made about the resulting decrease
in upward radiation at the wavelengths that CO2 absorbs.

3. We do, indeed, see very close to that expected decrease in upward
radiation in satellite observations.

4. We know the sensitivity of the climate in terms of degrees of
increased equilibrium temperature per watt per square meter of of
increased radiative forcing.

5. Over the past twenty years we have seen roughly the amount of
warming to be expected from all of the above.