[Vision2020] Amazonian Deforestation and Global Warming:Was:Ed theViking, Greenland, and Global Warming

[Paul Rumelhart]

Ted Moffett wrote:

> Paul and Roger have both not responded to credible scientific sources 
> I have presented to this list that questioned some of their claims on 
> scientific issues regarding global warming.  Paul once indicated he 
> would respond to my exposure of the junk science on global warming he 
> presented to this list, yet he never responded. 
>

Ok, here is my take on global warming.  I'm not sure why you care about 
it so much, since I'm not a trained climatologist, my two degrees in 
math and computer science have done little if anything to help me in 
this, and the few web pages I've read on the net without the help of a 
strong factual basis in this subject to help me critically evaluate them 
have probably not covered the subject completely nor evenly.  But here goes.

Is global warming happening right now?  My answer is yes.  The melting 
of the glaciers and a few other disparate facts that I've heard about 
here and there do seem to indicate to me that it is in fact happening.  
I could be wrong, I wouldn't be surprised, but that's the way it goes I 
guess.

Is this trend localized with respect to time or is it the start of a 
more permanent change (whatever the cause)?  I have no idea.  The amount 
of change of the climate over small timescales (< ~50000 years) seem to 
me to be chaotic at best.  If it were well understood, I wouldn't be 
running work units for climateprediction.net and we wouldn't have 
varying models that conflict.  Too many variables, in my uneducated 
opinion, to be very certain about this at all.  It could be that "small" 
perturbations in climate have happened many many times over the past 
half a million years or so since single celled life has learned how to 
make use of oxygen and multicellular life became prevalent.  Aren't we 
coming out of the last Ice Age and in a general warming trend, anyway?

Is the amount of carbon dioxide pumped into the air now massively more 
than has been there in the relatively recent past (~50000 years)?  I 
don't know the science behind the Antarctic ice cores.  I don't know how 
much weight to give them, because I don't know if there could be other 
causes for the amounts of carbon dioxide at the various depths.  What 
happens if the climate changes enough to melt the Antarctic ice a bit?  
Obviously, those years won't be laid down in the ice core record.  I 
don't know if it's possible for the amounts to change over time, and I 
don't know the methodology behind the extraction and measuring of that 
gas and wouldn't have the necessary background to be able to evaluate it 
if I did know it.  Have these levels been checked against cores spread 
over a large area?  Have they been compared with other ice cores from 
other continents?  I don't know.  However, I'm tending to trust the 
scientists on this one and to believe, for what it's worth, that carbon 
dioxide levels are unusually high right now.

How does the relative spike of carbon dioxide that is occuring right now 
affect the greenhouse effect exactly?  I know it affects it, but by how 
much?  Isn't the percentage of CO2 in our atmosphere really small?  Is 
the current amount past the point of no return now, or does it have to 
double or triple before it's really a problem?  How much does it 
correlate with the local rise in temperatures?  Is it the only cause?  
Would temperatures be a little lower right now without Man or a lot?  I 
have no idea.

Are there mitigating factors that will reduce this carbon surplus?  Such 
as increase in plant growth or other natural processes that may scrub 
CO2 from the atmosphere?  I don't know.  It seems to me that this should 
play some part, but I'm not a geophysicist or a biologist, or an expert 
in agriculture.

How variable is our nearest star?  Obviously, solar input is the 
greatest factor affecting temperature.  How stable is this source?  Does 
it fluctuate?  Is the amount of solar radiation hitting the planet now 
the same amount that hit it ~50000 years ago?  Again, I don't know.  I'm 
not an astronomer.

Anyway, there is my much-needed evaluation of the science of global 
warming.  Hope this helps. 

I would like to reiterate my "political" stance on this, which is that 
there are many other reasons to cut back on fossile fuels that aren't 
being so heavily debated right now that are just as important as global 
warming if not more so.  One big one being the fractious status of the 
Middle East and our dependence upon this region for our oil.  Notice the 
large hike in gas prices that has just occured.  Pollution, which causes 
health conditions right now, is also another very good reason to switch 
from gas and coal and other "dirty" technologies and to look for 
"cleaner" ones.  Finite energy supplies running out is another excellent 
reason.  When the oil is gone or is too hard to get to, our economy will 
probably collapse if we aren't forward-thinking enough.

It also seems to me that the topic of global warming has been 
politicized.  Of course, I'm not a political scientist, either.  I'm 
having a hard time sorting out what is general scientific consensus 
about the subject and what is politically motivated cruft.  That's not 
to say that current scientific consensus on one theory or set of 
theories necessarily means anything if the subject is wide-ranging and 
full of so many variables as this one is.  Even in "cleaner" sciences, 
such as astrophysics, you see that scientific opinion over the years 
sways from one theory to the next as more data trickles in.  And we 
aren't even affecting the universe in any significant way ourselves to 
muddy the waters.  I have no reason to believe that if we just stepped 
back and let the climatologists do their thing we would eventually get 
to all the answers.  I don't believe that we have all the answers right 
now.  You, apparently disagree.  I wish I was educated enough in the 
various disciplines involved to be able to give a definitive answer.

Paul