population trends must be examined in predicting water demand and anticipating scarcity issues.
Because population trends are an important variable in nearly all environmental security issues, this analysis begins by discussing population
trends on a regional scale. It then proceeds to consider three major environmental areas: global climate change, land-use issues of deforestation and
desertification, and water as a scarce resource. Climate change poses a significant risk because it has a high probability of occurrence and a potential
for severe consequences. Results from global climate models are employed
to predict the consequences of anthropogenic changes to the environment
[e.g., Aber et al. (2001); Dale et al. (2001)]. Risk assessment models have
been used to determine the range of impacts [e.g., Sutherst et al. (2000);
Utset and Borroto (2001)]. Further, ecological models assess the synergetic
effects and severity of impacts on specific biomes. Thus, modeling has been
key to identifying climate change as an issue and can be used to explore
effective solutions. Land-use issues are linked in both cause and effect to
climate change. The linkage between water and conflict is already well
established, with the concerns for the future being more fraught with danger
than at any other time in history.
15.2.1 Population Growth
Modeling of human population growth is certainly of interest to national
security analysts. Many estimates exist, with considerable variability in the
upper bounds and predicted rates of growth. One well-accepted model
predicts the world population will asymptotically approach 12 billion after
2100 (Getis 1998). The concept of “carrying capacity” can focus our understanding of the fundamental interrelationship between overpopulation and
environmental security. Carrying capacity is the total population that the
resources of an area can support over an indefinite period of time and is
graphically represented by a leveling off of the growth curve.
From a human perspective, this principle of carrying capacity holds, even
with the marvelous products of human ingenuity. Technology can change
the relative value of human carrying capacity by enabling us to satisfy
the demands for resources of one region at the expense of another, by
changing efficiency of use, and by providing solutions to many other
specific problems. However, the number of people any region can support
is finite [and, by extension, the total population the world can support is
limited; Brown and Kane (1994)]. Optimistic philosophies of human activity espouse the belief that technology can overcome the fundamentals
of carrying capacity; to date, this belief has not proven valid. The critical
resources of water and energy (food and fuel) are renewable at finite rates
on which technology can have only a minor impact. Ecological models offer
a means to assess ways to manage resources for environmental security
[e.g., Horie et al. (1992); Giampietro et al. (1994); Sahoo et al. (2001)].
15. Using Models for Environmental Security
291
Because population trends are an important variable in nearly all environmental security issues, this analysis begins by discussing population
trends on a regional scale. It then proceeds to consider three major environmental areas: global climate change, land-use issues of deforestation and
desertification, and water as a scarce resource. Climate change poses a significant risk because it has a high probability of occurrence and a potential
for severe consequences. Results from global climate models are employed
to predict the consequences of anthropogenic changes to the environment
[e.g., Aber et al. (2001); Dale et al. (2001)]. Risk assessment models have
been used to determine the range of impacts [e.g., Sutherst et al. (2000);
Utset and Borroto (2001)]. Further, ecological models assess the synergetic
effects and severity of impacts on specific biomes. Thus, modeling has been
key to identifying climate change as an issue and can be used to explore
effective solutions. Land-use issues are linked in both cause and effect to
climate change. The linkage between water and conflict is already well
established, with the concerns for the future being more fraught with danger
than at any other time in history.
15.2.1 Population Growth
Modeling of human population growth is certainly of interest to national
security analysts. Many estimates exist, with considerable variability in the
upper bounds and predicted rates of growth. One well-accepted model
predicts the world population will asymptotically approach 12 billion after
2100 (Getis 1998). The concept of “carrying capacity” can focus our understanding of the fundamental interrelationship between overpopulation and
environmental security. Carrying capacity is the total population that the
resources of an area can support over an indefinite period of time and is
graphically represented by a leveling off of the growth curve.
From a human perspective, this principle of carrying capacity holds, even
with the marvelous products of human ingenuity. Technology can change
the relative value of human carrying capacity by enabling us to satisfy
the demands for resources of one region at the expense of another, by
changing efficiency of use, and by providing solutions to many other
specific problems. However, the number of people any region can support
is finite [and, by extension, the total population the world can support is
limited; Brown and Kane (1994)]. Optimistic philosophies of human activity espouse the belief that technology can overcome the fundamentals
of carrying capacity; to date, this belief has not proven valid. The critical
resources of water and energy (food and fuel) are renewable at finite rates
on which technology can have only a minor impact. Ecological models offer
a means to assess ways to manage resources for environmental security
[e.g., Horie et al. (1992); Giampietro et al. (1994); Sahoo et al. (2001)].
15. Using Models for Environmental Security
291