Dave Ludlow wrote:
On Fri, 09 Mar 2007 15:19:57 +0000, Gianna wrote:

Bob Martin wrote:
in 221785 20070309 124614 Gianna wrote:

As the proportions of atmospheric gases vary over time, the term 'excess' is
subjective. They stated that temperatures, and CO2 levels, have been higher
than they presently are, and that was long before industrialisation etc..
Other sources claim that CO2 today is higher than at any time in the last 600,000 years.
Yes, they do.
As in any scientific debate, each camp is producing evidence in support of their
conclusions. I would have no idea which set of evidence is true in some
theoretical absolute sense. Unless someone on this group is a qualified climate
scientist with access to the primary source raw data (somewhat unlikely), then
none of us will know which side is 'correct' (if any).

From the posts I have read here, we are all reliant on the secondary sources
(or worse). So, we weigh up each case and decide which we think the most plausible.
We may then state which body of evidence and conclusion we believe - we may not
state which body of evidence is 'true' or 'correct' as we cannot know.

Gianna, I agree with your recollection of the main thrust of this
programme.

The AGW people need to answer scientifically the claim that carbon
dioxide emissions _follow_ the temperature changes - the latter is
said to be caused by changes in solar activity. The historic
comparison graph used to demonstrate that seemed to be quite
persuasive but it left me with several questions unanswered.

For example:

- What is the margin of error in the dating used to produce the graph
(of carbon doxide lag)?

I cannot find that (so far) but there are a number of references which show that
the rise in CO2 followed the rise in temperature, not vice versa. It is
mentioned discussed briefly at
http://www.realclimate.org/index.php...oncentrations/
but I haven't time to follow that further.

- Is it correct to say (as they did) that warmer ocean temperatures
lead to a greater release of carbon dioxide than cooler ocean
temperatures?

It seems to be correct:
"The decrease in solubility of gases with increasing temperature is an example
of the operation of Le Chatelier's principle."

http://www.intute.ac.uk/sciences/ref...em2/p01182.htm

I have many more questions - and an equal number for the GW
protagonists. I find both cases to be seriously lacking in solid
evidence never mind proof, when I look at the underlying assumptions.

There is too much circumstantial evidence, too few hard facts and too
many assumptions for my liking, on both sides.


Sadly that seems to be all there is, on either side. I suppose if there were
hard evidence either way, then there would be no debate.

I find the NCC view more probable, but as I make quite an effort to reduce my
consumption of finite resources (because they are both finite and expensive)
then even if I am wrong and AGW is right, there will be nothing more that I
could have done.

e.g. the only ordinary light bulbs I have left in use (3x 25w, 1x 40w) are in
fittings where it is not physically possible to insert the low wattage
fluorescents. They are seldom used - should that change I will need to change
the light fittings.


--
Gianna

http://www.buchan-meteo.org.uk
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