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fHuman vs. natural influences on the environment



My news server expired all articles last night, so I am unable to
generate a follow-up to the original.  I have updated the subject.

David Beorn <dbeorn@freenet.vcu.edu> wrote:
>Not in the least - you should be ashamed for propagating unsubstantiated 
>information.  

On the contrary.  The shame has always been yours.  Nudds
is a crank who subjugates his judgement to his politics.  You
either stooped to his level, or you were already there.

>> There is no serious question that human activities, specifically the
>> deforestation of large areas and burning of large amounts of fossil
>> carbon, have increased the amount of CO2 in the atmosphere steadily
>> and substantially.
>
>I have not contended that they aren't increasing CO2 - I only questioned
>whether they were the major contributor.

Over the last 50 years, the measured concentration of CO2 in the
atmosphere has increased at a rate which follows the human consumption
of fossil fuels like a train follows its rails.  There is no denying
this data.  Volcanic activity cannot account for it.   There is no
excess which could be due to unknown volcanism; instead there is a 
deficit, due to a sink which researchers are working hard to identify.

>I also dispute the contention
>that this is the cause of so-called "global warming" - what happened to
>the ice age many scientists were predicting a few decades ago???

Yes, the Earth is in what looks just like an interglacial period
of an ice age.  Yes, if nothing else had changed, the historical
record shows that we might expect glaciation soon.

Events have a way of changing things.  If your habits for the last
20 years had been to smoke, drink and eat to excess, you would
expect to be at risk of a coronary.  However, if you had not eaten
for 6 weeks, you would instead be at risk of death by starvation.
Your long-term history would have little to do with your immediate
situation.

The atmospheric concentration of CO2 has been characterized by
an annual cycle superimposed on a steepening curve of increase.
The annual cycle is due to uptake of carbon by plants in the
spring and summer, and release in the fall and winter (in the
Northern hemisphere, where most of the temperate zone lies).
The ramp is due to fossil-fuel use and deforestation; volcanic
activity levels do not correlate with it.

Datum:  In the last 10 years, the beginning of the spring drop
in global CO2 concentrations has moved forward by about a week.
Spring is arriving earlier than it has since these events started
being recorded.  The CO2 added by human activities traps heat
equivalent to an additional 2 W/m^2 of solar irradiation; the
solar variation due to the sunspot cycle is 0.5 to 1.0 W/m^2.

What does this indicate to you?

>What are the "right" things to read??  Sources that agree with
>YOUR contentions???  Give me some examples.  How about some source that
>has some integrity and will not compromise truth/true science for political
>or philosophical purposes. 

Try reading several sources in the non-specialist science press.
I can recommend Scientific American, New Scientist, Science News
and Discover.  These will often cite sources in the peer-reviewed
journals, which is about as uncompromising as you can get.  I
often see them print critical letters.  

What you will find is that there are some things which are not
disputed among the overwhelming majority of scientists.  The
human responsibility for the increase in global CO2 is one of them.
(There is considerable debate about the effects, of course.   The
data are not in, and the models disagree.)  However, political
reality is that unwelcome changes will be blamed on someone, and
the resulting conflicts may be easier and cheaper to prevent than
to solve, pay off or clean up after.

>The only real solution, I expect, to our contribution to the CO2 is for us
>to STOP making electricity, etc. by burning fossil fuels altogether.

Now that is simplistic.  Other solutions could be to create carbon
sinks to offset the sources, or to find ways to take the energy of
coal and oil without releasing the CO2 to the atmosphere.  As you
can see, I am not dogmatic.

>would that solve the "problem" we are seeing???  Or is the fluctuation of 
>ozone and maybe CO2 a natural phenomenon that we just haven't had enough 
>data to document yet??  The Ozone fluctuation has DEFINITELY been 
>documented as far back as 1956 - why is this ignored in these discussions??

Ozone fluctuates with solar EUV, which has the energy to create
atomic oxygen directly.  The decline in ozone we are seeing now
has been proceeding through the last solar maximum, when EUV
levels were highest.  The mechanism for the catalytic destruction
of ozone by chlorine has been demonstrated in the laboratory.
(Datum:  I am informed that approximately 25% of the chlorine in
the stratosphere is derived from methyl chloride emitted by ocean
sources.  That leaves 75% from human sources, not 100%.  This is
still an overwhelming anthropogenic contribution.)

If you are unaware of this, you have not been reading enough to be
informed.

>That is what YOUR source says - but my source says that volcanic gases 
>contribute FAR more to this than man.  

Cite your source.  Your source should be able to point to a smoking
gun, e.g. a month-by-month association of atmospheric CO2 levels
with world-wide volcanic activity over several decades.  If you
are satisfied without such strong evidence, you are overly
credulous or are making political rather than scientific judgements.

>No - just that we either don't know enough to make these conclusions or
>that we may in the future find info that contradicts it.  Just like we 
>recently "found out" that radon gas is not the harmful thing we said it 
>was 5 years ago.

Now you are over-generalizing.  The EPA et al. never had direct
evidence that radon in homes caused lung cancer.  Examination of
cancer data vs. geological levels of radon showed that the
association was small and perhaps negative.  What they did have
was an association between employment in uranium mines (which
have high radon levels) and lung cancer.  It doesn't take
a genius to realize that radon might not be the culprit.

This "discovery" about radon was no surprise to me, because I have
been reading better sources than our public policy-makers appear
to do.  I have known about this for at least 10 years.

Similarly, the relationship of radiation to cancer is very
tenuous at low levels, and the "zero threshold" model is almost
certainly defective.  Cancer does not increase with natural
cosmic radiation exposure between low-latitude sea-level sites
and high altitude or near-polar zones, for example.  This is a
fact.  It's not often reported in the popular press, but if you
read the right things, you will know.

>> You are not doing anything for your credibility.  If you will please take
>> your argument out of the sci.* hierarchy, you will do everyone a favor.
>
>I'm not the one who put it here 

That is not relevant.  If you want to take a crank to task, use
the truth, it works best.  If you want to have a discussion at 
the political mudslinging level, it doesn't belong in the sci
hierarchy.  I'd edit followups on this posting myself except
that this news-poster does not allow access to the full headers.



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