Re: Christopher Booker: "2008 Was The Year Man-Made Global Warming Was Disproved"

On Sat, 3 Jan 2009 01:46:18 +0000 (UTC), Paul J Gans <gans@xxxxxxxxx>
wrote:

--- snip ----

It is of concern that the models are unsuccessful at making even
qualitative predictions of the nature of changes in the earth's
atmosphere, let alone quantitative predictions.

Each model's success depends on its assumptions. Its assumptions
are limited by the amount of computing power available. For
instance, does including cloud cover in the equatorial regions
make a real difference? The only way to tell is to do two
computations, one including it and one not. But if you can't
do the one including it, well...

By about 2000 it was apparent that models were predicting temperature
rises about twice that observed. It was at this point that cloud
effects began to be seriously included in models. The problem was that
nobody really understood the mechanics of cloud formation, and this is
still likely to be the case. The contribution by Svensmark of the
possible role of Cosmic Rays has added another input variable and
further complicated our understanding of what is going on. The problem
is not lack of computing power but that we do not understand that
which we are trying to model.

But the knowlege of global warming does NOT come from models
alone. Indeed, they are a minor part of it.


I recall a discussion with one modeller about 10+ years ago when the
thermal properties of the sea were just beginning to be taken into
account (but no currents, no waves and no interaction with the
atmosphere). But even then models were predicting global warming. I
described my experiences with complicated models of engineering
systems and their sensitivity to _minute_ changes in the input data.
Even a stable model was lucky to get within 20% of real world
behaviour. The flapping of butterfly wings was rampant.

My friend agreed that climate models suffered from the same kind of
problems and, even then, they were so complicated that it was almost
impossible to track down where things were going off the rails. I
asked him "How can you tell a good model from a bad model?" I was
shaken by his reply "It all depends on whether or not it predicts
global warming". In this case it seems the map _is_ the territory, but
its not the world I live on.

It should be. You see, global warming is a FACT. You have
got to wrap your head around that.

What your friend was talking about was the ability of a given
model to predict the past 20 or 40 or whatever years of
climate history. That history shows warming. Scream all
you want, it is fact.

The problem is to determine how much of that is human caused.
I've given the example of CO2 in the air. We *know* that it
causes warming. And we *know* that humans have caused a huge
increase in the CO2 in the air.

Those that would deny human effects have to explain why the
CO2 is NOT causing warming. So far, nobody has even come
close.

Do you start to see what we are talking about?

You seem to take it for granted that CO2 causes global warming. This
is rather along the line of taking it for granted that pouring more
fuel into an engine will enable it to generate more power. Of course
this latter is a fallacy, for reasons which we understand. The problem
with accepting that CO2 necessarily causes global warming is that we
do not properly understand the mechanism.

John Christy (a lead author on IPCC 2001 has written:
++++++++++++++++++++++++++++++++++++++++++++++
Chase et al. (2003) examined the probability of finding a significant
difference in trends between the surface and troposphere over multiple
periods of twenty-two years in length using four climate model
long-term simulations. Experiments were studied for both unforced and
forced (i.e., greenhouse-gas enhancement) integrations. Their
conclusions include the result that at no time, in any model
realization,forced or unforced, did any model simulate the currently
observed situation of a large and highly significant surface warming
accompanied liy little or no warming aloft. Given the serious
uncertainties in the factors that control convection and radiation,
and considering the approximations employed in model simulations, I
suggest, consistent with Chase et al., that these climate models fail
to relinquish heat energy, which is apparently being incorrectly
retained in their atmospheres. And it is therefore likely that
long-term integrations of these models might not produce reliable
estimates of atmospheric temperature trends.

Though the thrust of the National Academy of Sciences (NAS 2001)
report promoted evidence for human induced climate change, its
conclusion about this surface/troposphere disparity was less firm:

The finding that the surface and troposphere temperature
trends have been as different as observed over intervals
as long as a decade or two is difficult to reconcile with our
current understanding of the processes that control the
vertical distribution of temperature in the atmosphere.

"Our current understanding" is a phrase that means the "results of
climate model simulations." What the NAS statement implies, then, is
that the inability to reproduce the behavior of so important a
quantity as the bulk atmospheric temperature and the energy content it
represents, is an inconsistency that should not be discounted when
trying to predict how the climate system may unfold.
+++++++++++++++++++++++++++++++++++++++++++++++++

How can we be so certain of the effect of CO2 on global warming when
we obviously do not understand the mechanics of the process
sufficiently well to properly model it?

It is not the concept of global warming to which I object, the planet
is quite clearly warming. I object to the certainty with which it is
being argued that a significant part of the observed global warming is
attributable to man. I don't think we are in a position where we can
properly say that.



Eric Stevens
.

Relevant Pages

  • Re: The Other Climate Theory: The Politics Behind Cosmic Rays
    ... eliminate the evidence that warming is caused by CO2. ... but has no relevance to global warming. ... earth atmosphere as a whole. ... Cloud formations set the temperature profile of the atmosphere. ...
    (soc.retirement)
  • Re: The Other Climate Theory: The Politics Behind Cosmic Rays
    ... eliminate the evidence that warming is caused by CO2. ... CLOUD is interesting science, but has no relevance to global warming. ... earth atmosphere as a whole. ...
    (soc.retirement)
  • Re: The Other Climate Theory: The Politics Behind Cosmic Rays
    ... eliminate the evidence that warming is caused by CO2. ... CLOUD is interesting science, but has no relevance to global warming. ... earth atmosphere as a whole. ...
    (soc.retirement)
  • Re: Whats Really Heating Up the Planet?
    ... "Carbon dioxide is 0.000383 of our atmosphere by volume," ... CO2 contribution today would be equivalent to the linoleum on the first ... said he doesn't even consider global warming among the Top 10 ...
    (soc.retirement)
  • Re: Solar cheaper than nuclear
    ... warmer summers that the current global warming ... so you assume that their predictions are as ... living with low CO2 levels for the past few million years, ... But where are the zillions of killer hurricanes that the AGW bunnies ...
    (sci.electronics.design)