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24
Report on
THE EFFECTS OF INCREASED ATMOSPHERIC CARBON
DIOXIDE
I. INTRODUCTION
Before the year 2020, the climate of the earth may be warmer than any time in
the past thousand years. This change, which is incredibly fast by geological
time scales, will be brought about by increased levels of carbon dioxide in the
earth's atmosphere. The most important source of excessive CO2 is the
burning of carbon-based fossil fuels for energy production. Carbon dioxide is
a by-product of all living systems and is normally considered harmless. It is a
minor element in the earth's atmosphere comprising only about 0.03% of the
total atmosphere. However, this small amount of CO2, along with water
vapor, is responsible for what is commonly known as the greenhouse effect.
The fact that changes in CO2 concentrations in the atmosphere could cause
changes in the earth's climate has been known for over one hundred years.
However, only in the last 5 to 10 years has significant research been done in
this field. The most ominous of the effects of a warmer climate will be the
shifting of local weather patterns. This shifting will have profound effects on
agricultural production in a world that is already unable to adequately feed its
citizens today. There will also be an accompanying redistribution of wealth
which will likely lead to dangerous social conflicts. It is obvious that the
continued introduction of CO2 into the atmosphere will have consequences
far worse than producing a slightly balmier climate.
The purpose of this report is to examine the climatic changes caused by
increased carbon dioxide in the atmosphere and their implications for society.
Also discussed will be the mechanisms of the greenhouse effect, the sources
and reservoirs of carbon dioxide, and some possible methods to reduce the
magnitude of the problem. Note, however, that the most we can do at this
point is lessen the severity of the situation. That the mean global temperature
will increase in the next few decades is certain. The only questions are how
much and how fast.
II. NATURAL WEATHER PATTERNS
The earth's climate naturally changes over extended periods of time.
Temperatures have been much warmer for 80 to 90 percent of the last 500
million years than they are today. The polar ice caps, for example, are actually
a relatively new phenomenon. They were formed 15 to 20 million years ago in
the Antarctic and perhaps as recently as 3 to 5 million years in the Arctic.
The climate is still dominated by natural cycles of warming and cooling. The
most influential of these natural weather patterns is the 180-year cycle. The
180-year cycle predicts that temperatures in the Northern Hemisphere reach a
minimum every 180 years. (Climate records for the Southern Hemisphere are
incomplete.) The bottom of the last cycle was in the early 1800s, which
suggests that we may now be in a period of peak coldness. The winters of
1976 through 1979, which were unusually bitter, seem to reinforce the theory
behind the 180-year cycle. This current cooling trend would mask any
warming caused by an increased greenhouse effect.
However, the 180-year cycle predicts a natural warming trend will
Section titles are
centered.
Introduction
provides
background
information and
reason for
report.
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