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environment and on natural global 
change. 
2 
Global Change and Man's 
Environmental Impact 
Man's impact on the earth's 
environment is perceived mainly as 
negative changes on the earth's 
"natural" state by man's 
activities. Obvious among these 
changes are pollution of the 
atmosphere, fresh water, oceans, 
and physical changes such as 
deforestation, erosion and urban 
development. While collec- tively, 
some of these global changes by man 
to the earth's environment may be 
significant and detrimental to 
man's existence as known today, 
these changes pale in scope when 
compared to the 4.5 billion years 
of dramatic, often violent, but 
con- tinual physical, chemical, and 
biologic global changes recorded 
throughout the earth's geologic 
history. To understand the signi 
ficance of man's impact on the 
environment, one must fully 
understand that man is a late comer 
in the earth's history and that man 
has evolved because of and in spite 
of major natural global change. 
Population Growth and Resource 
Needs 
To try and understand what man's 
impact on the environment is in 
order to determine which impacts on 
natural global change might be 
better managed, one must also 
understand what mankind is, where 
mankind has come from, and where 
mankind appears to be heading. One 
measure of this understanding of 
mankind is the historical and pro 
jected growth of mankind's popula 
tion and resource needs. 
An example of population growth, 
energy resource needs, and their 
concomitant impact on atmospheric 
C0 2 and global temperature increase 
or "warming" is seen in Figures 1- 
4. While the accuracy of these 
figures and numbers is not argued 
here, they are representative of 
many published data currently in 
vogue in the debate on global 
warming and change. Assuming them 
to be generally valid, several 
simple conclusions are reasonable 
for the period 1990-2010, such as: 
1. The world's population will 
increase by about 30%, or about 1.5 
billion people (Fig. 1); 
2. The world's energy 
consumption will continue to 
increase at a rate equal to or 
greater than population increase 
(Fig. 2); 
3. The increased energy 
consumption will lead to increasing 
C0 2 emissions (Fig. 3); 
4. Increasing global atmospheric 
C0 2 will probably parallel 
increasing global temperature , or 
"global warming" (Fig. 4). 
While these simple conclusions seem 
reasonable based on these and 
myriad other data, they are 
legitimately the subject of the 
growing great debate, not only for 
validity, but also for 
significance. Moreover, the debate 
applies to many other material 
products of man's activities, i.e, 
use of chlorofluorocarbons and the 
Antarctic "Ozone Hole" demonstrated 
by NOAA/NASA satellite 
observations. This grand 
environmental debate is of major 
importance to mankind in impending 
international political decisions 
as to how to manage man's 
environmental impact while 
prudently considering what 
environmental impacts are necessary