Dear all,
I've redone the calculations that deduce concentrations and temperature
from an emissions profile, based on a Hadley paper from last Nov as well as
the IPCC 1994/5 publications that I used when I first did this exercise in
1998/9.
I havent got time to stick the formulas into the XL version of ccoptions,
and am now away for most of the next two weeks so am unlikely to do that
before late Sept.
The new formulas should be used instead of the ones I sent out before. They
show a steeper temperature rise, and no longer use the concept of
1.5/2.5/4.5 degree sensitivity, which seems to have been quietly dropped as
the GCM modellers have got much better. They should also be OK at least up
to 750ppmv, as opposed to 650 before - there's still a need to check and
maybe amend to make sure the results look reasonable for a
business-as-usual case.
The formulas can be found (i.a.) in cells T7 and H7 in the two sheets,
which show the fit between my simple-model estimates, and the IPCC's and
HAdley's assertions about the output of their models.
Any suggestions for doing this better would be welcomed.
Cheers
Tony |
