On Dec 13, 10:28 pm, Alastair <[email protected]> wrote:
> On Dec 13, 8:45 pm, Hank Roberts <[email protected]> wrote:
>
> > > everyone knows that CO2 is saturated
>
> > Well, no, a fairly small group of people assert that everyone knows
> > that in theory but it needed to be tested.
> > It has been now:
>
> > See: http://ams.confex.com/ams/Annual2006/techprogram/paper_100737.htm
>
> Thanks Hank.
>
> They write:
>
> "The experimental fluxes are simulated well by the FASCOD3 radiation
> code. This code has been used to calculate the model predicted
> increase in surface radiative forcing since 1850 to be 2.55 W/m2. In
> comparison, an ensemble summary of our measurements indicates that an
> energy flux imbalance of 3.5 W/m2 has been created by anthropogenic
> emissions of greenhouse gases since 1850. This experimental data
> should effectively end the argument by skeptics that no experimental
> evidence exists for the connection between greenhouse gas increases in
> the atmosphere and global warming."
>
> I am not arguing "that no experimental evidence exists for the
> connection between greenhouse gas increases in the atmosphere and
> global warming." I am arguing that the heating effect is being under-
> estimated, which rather agrees with their results that show an
> increase of 3.5 W/m^2, 40% higher than the calculated value of 2.55 W/
> m^2. In Table 4 of the Extended Abstract, for CO2 the measured
> increase is 2.10 W/m^2, 60% higher that the model value of 1.30 W/
> m^2. That hardly points to climate science being settled!
>
> But I will have to study it a bit more closely because it seems to run
> counter to my ideas :-(
>
> Cheers, Alastair.
I've re-read the Extended Abstract for Evans & Puckrin a bit more
carefully now. They are arguing that there is an increase in back
radiation of 3.52 W m^-2 compared to 2.55 W m^-2 predicted by models.
This increase is mainly due to water vapour. But water vapour is
highly variable so that is unconvincing. Another major factor in the
increase is from other anthropogenic gases such as CFCs, which of
course will produce a new forcing. It is only CO2 that I claim is
effectively saturated, and only within the CO2 bands. In other words I
am claiming that any line broadening is not significant.
They have only one entry per table for measured CO2, unlike the other
gases (Why?) In Table 3a CO2 shows and increase of 3.8 W m^-2 up to
the year 2000, and Table 3b shows an increase of 0.0 W m^-2 up to the
year 1999. The later value agrees with what I claim, but the former
value does not. They make no attempt to explain the difference in the
two value and quote 2.10 W m^-2 as the Measured flux in Table 4, but
that is not even the average of the two values which is 1.90 W m-2.
Moreover, it is the colder winter season when the back radiation seems
to be greater.
Note that the "PAST" value is a modeled value. So they are comparing
the difference between a measured/modeled value with a modeled/modeled
value. Are they really claiming that by measuring the down-welling
radiation on two occasions (summer and winter) at only one
geographical location then they can deduce the changes in global
radiation over a period of nearly two centuries?
So, IMHO, a rather unsatisfactory paper, and that may explain why it
is appearing as an extension to a poster rather than as a peer
reviewed paper. I suspect that they could not get it published.
Perhaps someone would be prepared to defend them!
Cheers, Alastair.
, so I would comment on it here thought I would post and so am n a
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