Roy wrote:
Stan,

I did read the article as one of many whilst googling the subject. I
do apologise
for the link, it just happened to be the last (and most recent) that I
read.
There are several other items thrown up by google, indeed one from
NASA
which is probably more relevant. It seems that the thawing of the ice
caps on
Mars is freeing Co2 into the atmosphere.

The atmosphere of Mars is mostly CO2, and the polar caps in Martian
winter are cold enough to freeze it out. This leads to a variation in
atmospheric pressure and a net flux of CO2 from the summer pole to the
winter pole at least when the orbital elements are favourable.

Could it not be the case here
that the
warming is in fact CAUSING the increase in CO2 rather than BEING the
cause
of warming?

No. The CO2 in the air is changing due to the isotopic signature of
fossil fuels being burnt, and the rate of change of concentration is
consistent with the burn rate (and also with the measured decrease in O2
content). There is no doubt at all that the Earths atmospheric
composition is being altered by us burning vast amounts of fossil fuels.

The reservoirs of natural CO2 in the oceans have a different isotopic
signatures and so cannot be the source of the CO2 increase. In fact you
can determine that about 40% of all the CO2 we emit is dissolving into
the ocean and making it more acidic (and so changing the isotopic ratio
in the seas).

As I previously wrote, man has no effect on Mars and yet
it IS
warming. This suggests to me that this is a solar system wide event
and very little
to do with mankinds activities. Just my opinion of course, and it does
seem logical
to me, however I am open to discussion on this.

That Mars is warming isn't too surprising. It has extreme CO2 feedback
to any slight change in heat input - the atmospheric pressure there
changes rapidly with any slight increase in insolation. A reasonably
accessible summary of how the Martian climate behaves is online at:

http://www.mit.edu/people/goodmanj/t...ing/node6.html

And the Viking Lander pressure graphs are at:

http://www-k12.atmos.washington.edu/..._overview.html

No one disputes the fact that the suns output can vary slightly
(although satellite monitoring puts strict bounds on by how much). The
crucial point is that the natural climatic variation due to the sun over
the past century has been outstripped by the GHG induced warming in the
most recent three decades. It is time to wake up and smell the coffee.

Regards,
Martin Brown