Among other things, an objective
view of global warming is predicated on knowledge of our atmosphere
and weather. Part 2 of this series examines the composition
of earth's atmosphere and the nature of weather.
Since CO2 is referred
to as a "pollutant" and the primary (in some quarters, the only)
cause of global warming, this particular atmospheric gas is
examined together with the role it plays maintaining planetary
life and moderating earth's temperature to provide a suitable
environment for life on this planet. (More about the "greenhouse
effect" and what causes it in Part 4 of this series)
The cyclic nature of weather
is examined to reveal how long term climate trends cannot possibly
be extrapolated from relatively short periods of either global
warming or global cooling. Part 3 of this series examines climate
and natural warming and cooling cycles.
The planet we know as Earth
consists of three parts, the atmosphere, the hydrosphere, and
the lithosphere. The lithosphere is the solid portion of the
planet (soil, rocks, minerals). The hydrosphere consists of
all the planet's water, whether the oceans, lakes, rivers and
streams or ground water found within the lithosphere. The vast
portion of the hydrosphere is found in the oceans that cover
about 71% of the earth's surface and contain 97% of the planet's
water.[1] Finally, the atmosphere
is that gaseous portion of the earth that rests upon the hydrosphere
and lithosphere, extending hundreds of miles upward toward interplanetary
space.[2] All of these components
of the planet earth interact with each other and each contributes
to weather and climate. The impact of the hydrosphere on climate
and global temperature trends cannot be overlooked and will
be examined more closely in Parts 3 and 4 of this series.
First, a few definitions of
important terms:
carbon dioxide (CO2):
a colorless, odorless, incombustible
gas, CO2, somewhat heavier than air, that passes
out of the lungs in respiration: produced commercially and
used widely in fire extinguishers, carbonated beverages,
etc.: in photosynthesis, carbon dioxide and water are absorbed
by plants, which synthesize certain carbohydrates and release
oxygen into the air.[3]
pollutant: something
that pollutes; esp., a harmful chemical or waste material
discharged into the water or atmosphere.[4]
pollute: to
make unclean, impure, or corrupt; defile; contaminate; dirty[5]
weather: the
general condition of the atmosphere at a particular time
and place, with regard to the temperature, moisture, cloudiness,
etc.[6]
The Atmosphere
Earth's atmosphere is primarily
composed of nitrogen and oxygen which together account for 99%
of all atmospheric gases (78% nitrogen, 21% oxygen). The table
below lists the top ten components of the atmosphere in order
of their abundance:[7]
In addition to the gases listed
in the table above, water vapor is present in the atmosphere
in varying concentrations. Depending on season and region, water
vapor concentrations equate to a layer of water ranging from
less than 2 millimeters (in polar winter regions) to about 45
millimeters (in equatorial regions). If all atmospheric water
vapor were reduced to a layer of water encircling the planet,
that layer would be about 30 millimeters (1") thick.[8]
Oxygen
It is worth noting that these
figures have not been constant over geologic time. For example,
the concentration of oxygen at 20%-21% rose gradually to its
present level. However, despite natural production of oxygen
by plant photosynthesis, the level of oxygen is unlikely to
go higher as a result of oxygen consumption by fire. This balance
is critical to life on earth since an increase of 5% in atmospheric
oxygen relative to inert buffer gases would make plant life
so combustible that "prairies, forests,
and even tropical jungles [would]
constantly be catching fire, consuming oxygen, and increasing
carbon dioxide and ash particles in the atmosphere."[9,10]
Carbon Dioxide (CO2)
Similarly, atmospheric carbon
dioxide is known to have changed dramatically in the recent
geologic past:
"During the last
major glaciation, the amount of carbon dioxide in the atmosphere
fell drastically, by about 25%, reaching its lowest level
during the last 2,000 years of so of the Ice Age. . . . Then,
at about the time the interglacial began, carbon dioxide became
more abundant. Scientists have not yet pinpointed whether
the carbon dioxide level increased before or after the climate
changed ..."[11]
Carbon dioxide is constantly
produced and consumed by both natural and anthropogenic (resulting
from actions of mankind) forces. Natural production of CO2
is 29 times that produced by humans (anthropogenic) through
burning of fossil fuels and forest clearing.[12]
Fire, volcanic activity, insect and animal life and plant decay
are among the major natural sources of carbon dioxide. The most
significant contributor to anthropogenic CO2 is fossil
fuel burning, which accounts for about 75% of the anthropogenic
total with the remainder likely due to deforestation.[13]
One of the largest producers of CO2 "may
well be termites, whose digestive activities are responsible
for about ... 10 times ... the present [1990]
world production of CO2 from burning fossil fuel."[14]
To appreciate how small a portion
of the atmosphere CO2 makes, consider this example.
The driving distance from Hartford, CT, to San Fransisco, CA
is just under 3000 miles. If that distance were to represent
the total atmosphere, then you'd have to drive from Hartford,
CT, to 28 miles west of Cleveland, OH, to represent the portion
of the atmosphere consisting of oxygen. To represent the atmospheric
portion consisting of CO2, you'd have to drive from
Hartford, CT, just one mile down the road!
CO2 As A "Pollutant"
The negative impact of referring
to CO2 as a "pollutant" is not accidental. Time
magazine, in its April 9th edition (pp 30-31) depicts
CO2 emissions as belching black clouds from industrial
smokestacks - yet CO2 is both
colorless and odorless!
Since carbon dioxide occurs
naturally in our atmosphere and is a necessary ingredient for
plant life, why is it referred to as a pollutant? Doesn't seem
to fit the definition, does it? The Greening Earth Society
Virtual Climate Alert, Vol. 2, No. 32 (August 1, 2001) states:
"The insistence
that carbon dioxide (CO2) is a pollutant is puzzling
given literally thousands of experiments pointing to the reality
of CO2's function as a building block of nature.
Many within the environmental community either won't acknowledge
-- or refuse to accept -- the ecological benefits of a higher
concentration of carbon dioxide in the atmosphere."[15]
Of course, if one were determined
to make CO2 appear an evil substance to an
unwitting public, the term "pollutant" works quite well.
CO2 accounts for
only one-third of one-tenth of one percent of atmospheric
gases. However, since CO2 levels vary and there is
conflicting data that suggest concentrations ranging from 0.03%
to 0.05% (0.033% in the chart above), for the sake of this discussion
we'll assume the higher proportion to give the global warming
alarmists the figure they generally support. Estimates of anthropogenic
CO2 production during the past 200 years vary widely
from 5% (realistic) to as much as 22% (highly suspect) of total
atmospheric CO2. Yet, in order to reach the higher
figure, one must assume all the increase in CO2
during the past 200 years is from anthropogenic sources - a
highly dubious assumption, considering how little is understood
about natural CO2 variability during the past 600
million years. For the sake of this discussion, we'll again
give the global warming alarmists the generosity of assuming
anthropogenic sources account for a full 15% of total atmospheric
CO2.
Despite CO2 being
a far more efficient heat trap, clouds and water vapor (H2O)
account for "over 98% of the current greenhouse effect."[16,
17] Consequently, atmospheric CO2
cannot account for more than 2% of total greenhouse warming.
Anthropogenic CO2, even at the higher estimate of
15% of total CO2, would account for at most
0.3% of greenhouse warming (15% of 2%). If the more generally
accepted lower figure is assumed (anthropogenic CO2
only 5% of total CO2), then anthropogenic CO2
contribution to greenhouse warming drops from 0.3% to 0.1% -
one-tenth of one percent!
The greenhouse effect will be discussed in greater detail in
Part 4 of this series.
If there is anything that can
be said with certainty, it is that there is great uncertainty
about the contribution of anthropogenic CO2 to any
change in worldwide climate.
Weather
Recalling the definition of
weather as "the general condition of
the atmosphere at a particular time and place, with regard to
the temperature, moisture, cloudiness, etc.", it
is helpful to distinguish the difference between weather
and climate.
Returning to Webster's:
climate: the
prevailing or average weather conditions of a place, as
determined by the temperature and meteorological changes
over a period of years.[18]
Because climate is weather
characteristics and "changes over a period of years" a clear
understanding of climate demands a clear definition of the associated
time period. Obviously, we could define climate in terms of
whatever period of years we desire, however, because extreme
fluctuations in global climate have occurred repeatedly throughout
earth's history, it only makes sense to talk of climate in terms
of thousands of years. Climate will be discussed in far greater
detail in Part 3 of this series.
Since weather is associated
with a particular time and place, it is insufficient by itself
to suggest global changes in climate. For instance, a series
of particularly hot summers and/or mild winters in the northeastern
United States is simply a short-term weather trend and cannot
be used as evidence of climate change or global warming. Such
regional changes are often accompanied by corresponding opposing
changes in other regions. Weather trends are simply too short
to convincingly argue a case for climate change.
If long-term climate were to
change there would be an impact on regional weather cycles.
Clearly, weather was quite different in many regions during
the last glacial advance of the ice age. Yet, such changes are
so gradual and take place over such long time periods that associated
weather changes would not be noticed for many generations.
There are many natural phenomena
that can affect weather for a period of years without altering
long-term climate. Volcanic eruptions are noted for their impact
on worldwide weather. In 1815, the 13,000-foot volcanic mountain
Tambora on Sumbawa Island in the East Indies erupted with such
force that the top 3,700 feet of mountain vanished in a massive
cloud of dust and debris that produced what became known as
"the year without summer" in 1816.[19]
Areas of New England in the United States experienced snowfall
in every month of that summer and, as dust continued to filter
sunlight, the cooling effect of this eruption lasted for several
years until sufficient dust had settled to the ground. Reduced
sunlight from smoke and dust of long burning forest fires can
temporarily cool affected regions resulting in short periods
of cooler weather. However, the byproducts of these fires from
the combined effects of increased CO2 from burning
and decreased CO2 consumption from photosynthesis
are insufficient to produce changes in weather.
In short, weather will respond
to long-term climate changes, however, it is insufficient as
a predictor of those changes.
Footnotes:
Oberg,
James Edward, New Earths, p 50.
Matthews,
Willima H. III, Geology Made Simple, p 17.
Webster's
New World Dictionary of the American Language, 2nd College
Edition, p 213.
Ibid,
p 1103.
Ibid,
p 1104.
Ibid,
p 1610.
Matthews,
Willima H. III, Geology Made Simple, p 17.
Oberg,
James Edward, New Earths, pp 50-51.
Ibid,
p 55.
Lovelock,
J.E., Gaia: A New Look at Life on Earth, p 84.
Ice
Ages from the Time-Life Books series Planet Earth,
p 158.
Easterbrook,
Gregg, A Moment On The Earth, p 296.
Summary
for Policymakers - A Report of Working Group I of the Intergovernmental
Panel on Climate Change, p 7.
Lindzen,
Dr. Richard S. (Alfred P. Sloan Professor of Meteorology,
Massachuesetts Institute of Technology) in Global Warming:
The Origin and Nature of the Alleged Scientific Consensus,
6th paragraph.
Easterbrook,
Gregg, A Moment On The Earth, p 295.
Webster's
New World Dictionary of the American Language, 2nd College
Edition, p 266.
Volcano
from the Time-Life Books series Planet Earth, p 60.
