| Editorial
A Cold
Hard Look at Global Warming
By Robert Maynard
The
Legislature is finally in session and one would think that their main focus
would be finding a way out of the fiscal crisis that has us heading "Off
the Rails". (For those who have yet to view the Ethan Allen Report: http://www.ethanallen.org/pdf/OffTheRailsFINAL.pdf
) Instead, what seems to be getting the most attention is a heroic attempt
on the part of our political leadership to save us from the threat of global
warming.
As
Rob Roper points out in a January 16th article on this site entitled "Shaman"
Shumlin? Is Vermont becoming an environmental theocracy?" this quest
has taken on religious overtones complete with messianic pretensions. Apparently,
according to "Shaman Shumlin", even Governor Douglas has joined the faith.
Perhaps, before joining in a full scale revival, we might want to examine
some of the cold hard facts regarding global climate change.
The
first order of business is to get a bit more realistic regarding the timeframe
we look at when assessing climate change on a global scale. I have often
wondered why most of the analysis of so-called global climate changes deal
with such a short time frame when one considers that the earth has been
undergoing 100,000 year cooling and warming cycles for several hundred
million years. In hopes of addressing this problem I went to the web site
of the PaleoMap Project http://www.scotese.com/Default.htm.
Of course there are smaller cycles within the larger cycles, but overall
the earth has ranged from a low of about 12 deg. C for an global average
temperature (right about where we are now), to a high of about 22 deg.
C for an average global temperature. Given the fact that we are in
a low average global temperature cycle, it should come as no shock if we
see some warming. (See figure below from the Paleomap Project)
The
question is whether CO2 concentration is a contributing factor. Consider
this bit of information from the Paleomap Project:
Earth's
atmosphere today contains about 380 ppm CO2 (0.038%). Compared to former
geologic times, our present atmosphere, like the Late Carboniferous atmosphere,
is CO2- impoverished! In the last 600 million years of Earth's history
only the Carboniferous Period and our present age, the Quaternary Period,
have witnessed CO2 levels less than 400 ppm.
Global
Temperature and Atmospheric CO2 over Geologic Time
Late Carboniferous
to Early Permian time (315 mya -- 270 mya) is the only time period in the
last 600 million years when both atmospheric CO2 and temperatures were
as low as they are today (Quaternary Period ).
Note
two things here:
1)
The present time represents a low period for CO2 concentration.
2)
There is no correlation between Average Global Temperature and CO2 concentration.
While
it is logical to expect that the globe might be warming up a bit, considering
we are at a low point temperature wise, it is not at all clear that a little
global warming is a bad thing. It is also highly unlikely that humans have
much, if any impact on global climate changes. Consider this from
the Paleomap Project:
From
an historical perspective, global warming has saved us, at least temporarily,
from an Icehouse Climate, although humans can hardly take the credit.
Science
is clear on what controls cycles of climate change. Global warming (and
cooling) cycles are controlled primarily by:
1)
Cyclical variations in the sun's energy output
2)
Eccentricities in Earth's orbit
3)
The influence of plate tectonics on the distribution of continents and
oceans
4)
The so-called "greenhouse effect," caused by atmospheric gases such as
gaseous water vapor (not droplets), carbon dioxide, methane, and nitrous
oxides, which help to trap radiant heat which might otherwise escape into
space.
The "greenhouse
effect" actually is a bit player in global climate (although without its
benefits the average temperature of the Earth would be minus 18° C).
Human's did not cause the greenhouse effect, but critics maintain human
additions to atmospheric greenhouse gases may cause global temperatures
to rise too much.
Generally
understood, but rarely publicized is the fact that 95% of the greenhouse
effect is due solely to natural water vapor. Of the remaining 5%, only
0.2% to 0.3% of the greenhouse effect (depending on whose numbers you use)
is
due to emissions of carbon dioxide and other gases from human sources.
If we are in fact in a global warming crisis, even the most aggressive
and costly proposals for limiting industrial carbon dioxide emissions would
have an undetectable effect on global climate. However, significant efforts
to limit the emission of greenhouse gases in the United States are currently
underway.
Carbon
Dioxide from all coal burning worldwide comprises only 0.013% of the greenhouse
gases in Earth's atmosphere.
Perhaps
we should demand that our wannabe saviors drop their messianic pretensions
and do a little more homework. While we all want cleaner air to breath
and lowering CO2 emissions is a worthy goal in achieving that end, we discredit
this effort with preposterous claims that man made emissions are causing
significant global climate changes.
--
Robert Maynard lives in Williston
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