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OCR for page 117
The Medical Implications of Nuclear War, Institute of
Medicine. ~ 1986 by the National Academy of Sciences.
National Academy Press, Washington, D.C.
Nuclear Famine: The Indirect
Effects of Nuclear War
MARK A. HARWELL, PH.D., ~d
CHRISTINE C. HARWELL, J.D.
Cornell University, Ithaca, New York
INTRODUCTION
Over a 2-year period, the Scientific Committee on Problems of the
Environment (SCOPE)-Environmental Effects of Nuclear War (ENU-
WAR) project involved the participation of about 100 physical and at-
mospheric scientists and an additional 200 agricultural and ecological
scientists from more than 30 countries around the world in a unique
undertaking to assess the global consequences of nuclear war. The at-
mospheric scientists convened in a series of workshops, taking stock of
their ongoing research and identifying the next issues to be examined with
their computer models. From this emerged the characterization of the
projected nuclear war-induced disturbances in the global atmosphere, with
specified uncertainties and research needs (Pittock et al., 1985~. We on
the biological side did not have the luxury of existing funded laboratory
and modeling research projects on the consequences of nuclear war; in-
stead, our mission was to inspect the current information, models, and
understanding of how biological systems respond to stress. From these
data and models, developed for reasons far removed from considerations
of nuclear war, we synthesized a portrait of the global world after nuclear
war (Harwell and Hutchinson, l9SS). The focus was on human population
impacts mediated by disruptions in ecological, agricultural, and other life-
support systems.
The consensus that developed was stark: the indirect effects of a large-
scale nuclear war would probably be far more consequential than the direct
117
OCR for page 118
118
PHYSICAL EFFECTS AND ENVIRONMENTAL CONSEQUENCES
effects; and the primary mechanism for human fatalities would likely not
be from blast effects, not from thermal radiation burns, and not from
ionizing radiation, but, rather, from mass starvation. Whereas the direct
effects of such a nuclear war could result in several hundred million human
fatalities, according to several studies (e.g., Bergstrom et al., 1983; Am-
bio, 1982), the indirect effects could lead to the loss of one to four billion
lives.
This conclusion is derived from considerations of the vulnerabilities of
ecological and agricultural systems to the types of disturbances potentially
associated with the occurrence of a large-scale nuclear war. Thus, the
biological analyses were not linked to any specific nuclear war scenario
or to any single specific projection of alterations in the physical environ-
ment. This disassociation with particular scenarios was sought to avoid
being limited by the current uncertainties of the physical estimates. Many
of these uncertainties are irreducible, such as the specific details of an
actual nuclear war, details that would only become certain as the war
itself developed. Other uncertainties can be reduced by further investi-
gations, such as the processes controlling smoke emissions and scavenging
in the atmosphere. However, we cannot delay making biological and,
especially, human impact assessments until such issues become fully re-
solved. By examining the vulnerabilities of biological systems to classes
of perturbations, our results can be applied to a full range of possible
physical outcomes of nuclear war. Moreover, since the biological systems
were found to be so sensitive to nuclear war-induced stresses, consensus
was reached on biological responses and human impacts with perhaps less
uncertainty than remains for the physical estimates.
The categories of potential physical nuclear war-induced stresses that
were examined are listed in Table 1. There was an emphasis on the effects
from climatic disturbances, discussed in detail below, but other mecha-
nisms for indirect effects were examined, including, in particular, effects
from ionizing radiation and from increased levels of ultraviolet light. The
climatic stresses were categorized with respect to the types of biological
issues of importance. Specifically, an acute phase of climatic disturbance
characterized by an abrupt onset of lowered temperatures and associated
reductions in sunlight was identified as representing the potential envi-
ronment in the first few days to weeks after a nuclear war. No single
temperature or light decline was assumed; rather, the vulnerability of
biological systems to brief episodes of chilling or freezing temperatures
was examined. Similarly, for chronic-phase climatic disturbances, the
vulnerability of biological systems to a few degrees' (Celsius) reduction
in average temperatures persisting over the growing season, accompanied
by 5-20 percent reductions in sunlight and possible decreases in precip-
itation, was evaluated.
OCR for page 119
NUCLEAR FAMINE: THE INDIRECT EFFECTS OF NUCLEAR WAR 1 19
TABLE 1 Nuclear War-Induced Stresses Examined
Climatic
Acute
Temperature episodes of chilling or freezing
Light-episodes of 1-10 percent normal insolation
Chronic
Temperature average decreases of 1°C, 3°C, 5°C, 7°C, 10°C
below nodal over growing season
Light associated reductions in insolation by 5-20 percent
Precipitation- reductions by 25-50 percent
Radiation
Local fallout
Global fallout
Focus on external gamma doses
Other stresses
Fire
Ultraviolet-B radiation
Atmosphenc pollutants
In order to make these evaluations, no single set of experimental data
was available; instead, a number of lines of reasoning were drawn on to
exploit the full range of relevant information, including historical analogs,
statistical analyses, laboratory physiological studies, simulation models,
and expert judgment. The historical approach involved examination of
specific episodes of environmental stresses and responses which have
actually been experienced. For instance, incidents of freezing events in
subtropical regions (e.g., Florida and southern Texas) were examined for
their effects on fish populations, fruit trees, and other biological systems.
Statistical analyses were done on data representing multiple years and
multiple locations to determine the relationships among the physical en-
vironment and biological systems. For instance, the relationship between
the average air temperature experienced over growing seasons and the
length of the frost-free period (a measure of growing season duration) was
characterized statistically. Laboratory data were evaluated for physiolog-
ical-level information, such as the growth rates of crop plants under lab-
oratory conditions of different levels of temperature, light, moisture
availability, and air pollutant exposures. Computer simulation models of
ecological and agricultural systems were used for assessing the effects of
chronic alterations in climate on crop yields and ecosystem productivity.
And the judgment of scientists with expertise in specific agricultural and
ecological systems was relied on to identify and evaluate available data
and models and to extrapolate beyond the current experimental and his-
torical records to obtain the best estimates of biological system responses
to nuclear war. For the most part, the physiological-level data and expert
OCR for page 120
120
PHYSICAL EFFECTS AND ENVIRONMENTAL CONSEQUENCES
judgment were used to evaluate acute vulnerabilities, and the less extreme
perturbations associated with chronic-phase conditions were more suited
to histoncal, statistical, and computer simulation analyses.
These approaches were applied to each major biome type (Table 2 and
Figure 1), covering freshwater, manne, and terrestrial ecosystems from
the Arctic to the Southern Ocean and including the main grain crops in
the northern temperate, Topical, and southern temperate regions of Earth.
A number of international conferences were convened, each of which
specifically addressed particular system types: northern temperate eco-
systems were addressed at Toronto, Canada; northern temperate agncul-
ture at Essex, United Kingdom; Topical ecological and agricultural systems
at Caracas, Venezuela; Southern Hemisphere extratropical ecological and
agricultural systems at Melbourne, Australia; and general biological re-
sponses to radiation at Pans, France. Other conferences dealing with more
generic biological issues were held in Stockholm, Sweden; New Delhi,
India; Leningrad, USSR; and Essex, United Kingdom. A special confer-
ence on the experiences and extrapolations from the Japanese nuclear
bombings was convened in Hiroshima and Tokyo, Japan. At each con-
ference, as broad a consensus as possible was sought among the experts,
TABLE 2 Biome Approach to the Ecological
Evaluations
Northern Hemisphere terrestrial ecosystems
Arctic and boreal
Deciduous forests
Coniferous forests
Grasslands
Arid and semiarid
Northern Hemisphere aquatic ecosystems
Freshwater
Marine
Estuarine
Tropical ecosystems
Evergreen rainforests
Deciduous forests
Montane-cloud forests
Alpine
Grasslands and savannahs
Mangroves
Southern Hemisphere extratropical ecosystems
Australian ecosystems
New Zealand ecosystems
Southern Ocean and Antarctica
OCR for page 121
121
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OCR for page 122
122
PHYSICAL EFFECTS AND ENVIRONMENTAL CONSEQUENCES
with identification of unresolved issues and research needs. Many of the
latter were addressed within the ENUWAR project itself, with specific
statistical and computer simulation analyses being initiated. We used the
reports of the various conferences, the results of the commissioned anal-
yses, and additional studies conducted by the ENUWAR teams at Cornell
University and the University of Toronto as the bases for writing Volume
II of the ENUWAR report. This was subjected to an extensive review
process, during which we ensured faithful representation of the consensus
of the participants of the conferences; the completed book (Harwell and
Hutchinson, 1985? provides the technical basis for the conclusions pre-
sented here.
ECOSYSTEM VULNERABILITIES
The vulnerabilities of ecological systems were found to differ among
ecosystems, types of disturbances, and time of year. For example, tem-
perate forests were found to be most sensitive to acute, extreme temper-
ature changes that occur during the spring or summer, whereas marine
ecosystems were quite tolerant to changes in air temperatures. However,
marine ecosystems were found to be very vulnerable to disruptions in the
levels of incident sunlight, with acute reductions in insolation resulting
in the collapse of phytoplankton and, perhaps, zooplankton populations
on a large scale. Grassland ecosystems and the wheat-growing areas of
Australia were assessed to be most vulnerable to chronic disturbances in
precipitation, which is during the summer in the case of African grasslands
and during the winter in the case of Australian wheat-growing areas.
These conclusions were based primarily on the understanding of plant
responses to light, temperature, and moisture levels; by contrast, animal
responses, especially with respect to propagation of effects from one
species to another through species-species interactions, were considered
to be more speculative and probably never fully predictable. It is clear
that inadequate data bases and simulation model resources exist for precise
characterization of ecosystem responses, particularly to the less extreme
range of physical disturbances. Nevertheless, the various approaches out-
lined above suggest the cross-system vulnerability estimates provided in
Table 3.
Other analyses addressed the prospects for recovery for various eco-
systems and the processes by which recovery could be affected. The
consensus was that nuclear war-induced disturbances to the environment
would include virtually every environmental problem of concern today-
habitat destruction, species extinction, air pollutants, toxic chemicals, acid
precipitation, ozone depletion only on a scale of totally unprecedented
OCR for page 123
NUCLEAR FAMINE: THE INDIRECT EFFECTS OF NUCLEAR WAR 123
extent and intensity. Precisely what the full ecological ramifications of
such stresses would be and the specific pathways that subsequent recovery
would follow are urgently in need of a concerted research effort in the
general field of stress ecology. Other considerations, however, show clearly
that even without any disturbance to ecosystems, these natural systems
could support only a very small fraction, on the order of 1 percent or less,
of the current human population on Earth. The reason for this is that there
would simply not be the base of utilizable energy sufficient to maintain
5 billion people if we did not have agricultural and other human-controlled
systems to rely on. Thus, the carrying capacity of natural ecosystems is
greatly exceeded by the current human population, and disruptions in
human support systems that would force humans to rely substantially on
natural systems for sustenance would necessarily lead to reductions in the
human population. This fact provides the overriding incentive to examine
the vulnerability of agricultural and food distribution systems to disruptions
following a nuclear war.
AGRICULTURAL VULNERABILITIES
An examination of the vulnerabilities of agricultural systems showed
that these systems are the most sensitive of any biological systems to
changes in climatic conditions. There are several mechanisms by which
climatic alterations translate into reductions or loss of crop yields. For
most agricultural crops, temperature is the critical variable, although many
crops are also sensitive to changes in precipitation and others can be limited
by insufficient sunlight. Our studies focused on grain crops because these
contribute the majority of the caloric inputs into the human diet on the
global scale and because these crops are more effectively stored than most
other food crops (e.g., fruits), a factor that could be critical in the aftermath
of a nuclear war. Considering first the effects of temperature on grain
yields, a number of factors are important:
1. Brief episodes of chilling or freezing temperatures The occurrence
of even short-duration events of freezing temperatures during the growing
season leads to loss of grain yields, as demonstrated in laboratory exper-
iments and in the historical record; for example, in 1816 (the year without
a summer) a series of frosts occurred during June through September,
resulting in the loss of grain crops in the northeastern United States, eastern
Canada, and western Europe. The occurrence of such episodes following
a nuclear war could be expected to happen during the acute period, when
average temperatures might be reduced by tens of degrees Celsius for
days to weeks. Because of cloud patchiness during the period of early
smoke cloud development, it could be expected that even greater tem
OCR for page 124
124
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OCR for page 126
126
PHYSICAL EFFECTS AND ENVIRONMENTAL CONSEQUENCES
perature reductions could occur for brief periods of time. Furthermore,
during the chronic period that would extend into growing seasons one or
more years after a nuclear war, average temperature reductions of rela-
tively small amounts (in the range of 1°C-5°C) would be associated with
episodes of chilling or freezing events. The historical record indicates that
years with extreme low temperatures during the growing season (e.g.,
1816) had average temperature reductions of less than 1°C, which none-
theless caused large crop losses.
2. Insufficient growing season length- Associated with the average
reduction in temperatures over the spring-summer months, which is ex-
pected during a chronic post-nuclear-war period, would be a shortening
of the length of the growing season, with delay in the occurrence of the
last day of freezing temperatures in the spring and an early onset of freezing
temperatures in the fall. Several lines of evidence indicate that in the
Northern Hemisphere continental regions of the mid-latitudes (i.e., the
main grain-producing areas), on average, a 1°C reduction in average tem-
perature correlates to a 10-day reduction in the growing season length.
For example, Figure 2 shows the average temperatures and growing season
lengths for several locations in the United States over a several-year period.
The importance of this phenomenon can be seen when a growing season
is shorter than the growing season length requirements of the crop in order
for it to reach maturity and produce a yield. Exacerbating this problem is
the fact that reduced growing season temperatures result in the slower
development of crop plants, thereby increasing the growing season length
requirements for the crop to reach maturity. More on the growing season
limitation aspects will be discussed below.
3. Insufficient growing degree-days-The term thermal time is used
as a measure of the number of hours during the growing season that air
temperatures exceed a specified base level by venous amounts and is
calculated by multiplying the amount of time that the air temperature
exceeds the base level times the increment of temperature above that level.
For example, for a base level of 10°C, 2 days with a temperature of 20°C
would have the same thermal time as 1 day with a temperature of 30°C
(i.e., 20 degree-days). As with growing season requirements, each variety
of crop plant has a particular requirement for a total amount of thermal
time, measured as growing degree-days, that is needed in order for the
crop to mature. Below the threshold for thermal time, maturity does not
occur and grain yields are lost. Again, during the chronic period after a
nuclear war, the thermal times may be too low for grain production.
4. Insufficient integrated sunlight time A similar situation exists for
the numbers of hours during the growing season during which sunlight
levels exceed a certain amount. Simulations of Canadian wheat production
showed that reductions in insolation by about 20 percent over the growing
OCR for page 127
NUCLEI FAMINE: THE INDIRECT EFFECTS OF NUCLEI Wit 127
Climate cats 1955, 65, 75
20
.
~8 L ~
Mean annual 14
temperature .
|8 L.
0 50 1 00 1 50 200 250 300
Frost-free length (days)
FIGURE 2 Relationship between mean annual temperature and duration of frost-
free period. Source: Harwell et al. (1985, p. 2791. Repnnted with permission
from the Scientific Committee on Problems of the Environment (SCOPE).
season led to a total loss of yield because the required threshold level was
not exceeded.
Thus far we have looked at mechanisms by which temperature and light
reductions would lead to a total loss of crops for the growing season. In
addition, the altered climate could be sufficiently benign so that some
productivity remained possible, but the yields could be substantially re-
duced from current levels. The mechanisms are as follows:
5. Reduced productivity in response to the physical environment-
Laboratory data show those circumstances under which the thresholds of
stress that would eliminate production are not exceeded, but less than
optimal conditions reduce yields. These can result from reduced temper-
atures, reduced light levels, and reduced precipitation levels. As an ex-
ample of the latter, the historical record and computer simulations indicated
that wheat yields in Australia are essentially linearly reduced with reduc-
tions in rainfall; i.e., a 25 percent reduction in precipitation could be
expected to result in at least a 25 percent reduction in yields.
6. Disruptions in energy inputs to agriculture The considerations to
this point have focused on the yields that would be possible assuming
continued high levels of energy inputs to agriculture, e.g., inputs of fer
OCR for page 128
128
PHYSICAL EFFECTS AND ENVIRONMENTAL CONSEQUENCES
tilizers, pesticides, herbicides, fuel for tilling and harvesting, machinery,
etc. However, in the aftermath of a large-scale nuclear war, the availability
of these subsidies to agriculture, in combatant counties and in noncom-
batant countries that rely on other countries for energy and commodity
imports, would be severely disrupted or eliminated. Current yields of
grains are heavily dependent on such energy subsidies, as demonstrated
in Figure 3, which shows the tremendous increase in yields over the last
four decades. This is largely in response to increases in energy subsidies.
Assessments indicate that even in the absence of any climatic disturbances,
disruptions in agricultural subsidies could lead to reductions in crop pro-
duction by up to SO percent.
The Agriculture Canada mode] of spring wheat production illustrates
the potential effects of chronic climatic alterations on crop production
following a nuclear war (Figure 4~. A map of the wheat-producing prov-
inces of western Canada shows Me current boundaries for wheat production
and the boundaries associated with a reduction in temperatures over the
growing season on average by 1°C, 2°C, 3°C, and 5°C. The 1°C reduction
in average temperature results in a decrease in the potential growing area
by a relatively small amount, but a 2°C reduction in average temperature
MEAN RICK YIELD
3200
3000
2800
KGIHA
/
/
2600
2400
2200 ~
2000
1800
1 600
1400 ~
1945 1955 1965
YEAR
/
/
1975 1 985
FIGURE 3 Mean rice yield. Source: Harwell et al. (1985, p. 343). Reprinted
with permission from the Scientific Committee on Problems of the Environment
(SCOPE).
OCR for page 129
129
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OCR for page 130
130
PHYSICAL EFFECTS AND ENVIRONMENTAL CONSEQUENCES
eliminates the majority of the growing areas; a 3°C reduction would result
in the complete elimination of any wheat production in Canada. This
effect follows both from the reduction in the growing season length and
in the insufficient levels of thermal time. Similar results were found for
all other crops simulated, including crops that grow in much warmer
climates such as soybeans (for which only a 4°C-6°C reduction in average
temperature would eliminate yields in the southern United States).
Rice was evaluated in particular because of its large share of the human
diet on a worldwide basis and because a disproportionate number of im-
mediate post-nuclear-war survivors would live in tropical and subtropical
regions. We found that rice is the most sensitive of the grains to temper-
ature reductions and that rice yields can be eliminated even in the absence
of frost. In fact, at certain times during the growing season, temperatures
below 15°C lasting for only one or two nights would be adequate not to
kill the rice plants but to preclude the formation and maturation of the
rice grains. The historical evidence of rice production in Japan adds con-
siderable support to the conclusion that rice is extremely sensitive to
temperature; for example, when average summer temperatures are reduced
in Japan by 1°C-2°C, crop failure occurs.
From these and many other analyses and considerations, the strong
consensus that emerged among the agricultural scientists associated with
ENUWAR is that the acute phase of climatic disturbances could eliminate
grain production in the Northern Hemisphere following a large-scale nu-
clear war that occurred in the spring or summer and perhaps at other times
of the year. Furthermore, the chronic-phase climatic conditions could also
be expected to result in severe reductions or total elimination of yields of
Northern Hemisphere grain crops, and Southern Hemisphere crops could
also be adversely affected. Superimposed on these responses would be
severe reductions in yields in response to the loss of energy subsidies,
reductions in precipitation, and loss of arable land in combatant countries
because of radioactive fallout. Additional yield reductions could follow
enhanced levels of ultraviolet light and air pollutants. Clearly, there are
multiple mechanisms by which food production could be disrupted on at
least a hemispheric scale. A critical point in this is that these disruptions
would occur at climatic disturbances at the very low end of the range of
climatic changes projected to be likely to occur; thus, many of the un-
certainties associated with climatic projections are irrelevant to the impacts
on food production, since the levels of temperature changes under dis-
cussion (e.g., tens of degrees Celsius average decreases in air temperatures
in the grain-producing areas of the Northern Hemisphere for a spring-
summer nuclear war) well exceed the thresholds necessary for elimination
of grain yields.
OCR for page 131
NUCLEAR FAMINE: THE INDIRECT EFFECTS OF NUCLEAR WAR 131
VULNERABILITY TO DISRUPTIONS IN FOOD AVAILABILITY
These conclusions of the potential for massive disruptions in food pro-
duction must be examined to assess the potential impact on humans. Since
we cannot predict precisely by how much food production would be
affected, because of the climatic and nuclear war scenario uncertainties
discussed above, we again focused on the vulnerability of the human
population to disruption in food production for 1 or more years. The key
issue here is the amount and duration of food stores distributed around
the world.
In order to make this assessment, we examined data from the U.N.
Food and Agriculture Organization and other sources for 15 countries on
the quantities of grains stored, the current and estimated immediate post-
nuclear-war population levels, the age structure of the population, and the
minimal caloric consumption rates that humans require for subsistence.
These 15 countries include about 65 percent of the human population and
were selected to represent the range of situations in the world, including
highly industrialized nations, likely combatants, underdeveloped coun-
tries, Northern and Southern Hemisphere locations, tropics and temperate
regions, and various population densities. Included in the analyses are the
United States, the USSR, China, India, Australia, Japan, Costa Rica,
Nigeria, and others. In addition, we acquired less extensive data to analyze
the situation in 120 other countries, representing almost the entire world's
population. Some simplifying assumptions were required: (1) grains were
assumed to be fed only to humans, diverting the large quantities that
currently are designated for animal feed; (2) the diet was assumed to
chance to crimarv reliance on grains as opposed to current patterns of
--I- -- rid ~ - ~ ~ ~
consumption; (~) no imports or exports or grains or energy supplies were
assumed to occur in the aftermath of a large-scale nuclear war; (4) grain
stores in combatant countries were assumed to be destroyed approximately
in proportion to the loss of human life from direct effects of nuclear
detonations, and (5) within each country, food distribution was assumed
to work perfectly, such that each person would receive exactly the minimal
amount needed for survival; furthermore, if it was found that there would
be insufficient food to keep the full population in the country alive for 1
year, Den the maximum numbers of people that could be maintained were
assumed to consume all the food stores, and no food was assumed to be
eaten at all by those eventually doomed to starvation. Clearly this last set
of assumptions provides a very considerable overestimate of the number
of people that the food stores would actually keep alive and provides the
physically limited upper value for population maintenance. The issues of
societal disruption and other factors that could lead to a less-than-perfect
OCR for page 132
132
PHYSICAL EFFECTS AND ENVIRONMENTAL CONSEQUENCES
distribution of food in the aftermath of a nuclear war were not analyzed
but require a concerted scientific study.
The picture that emerged from the calculations of the food supply is as
follows:
1. For a very few countnes, specifically those that are the major grain
exporters, such as the United States, Canada, and Australia, the grain
stores are, in principle, sufficient to keep the surviving population alive
for a few years. Again, other factors might change this conclusion if food
were not appropriately distributed, and long-term sole reliance on such
grains could lead to nutrient deficiencies that were not calculated in our
analyses. Also, these would likely be combatant countries, so the direct
effects of nuclear detonations would be extensive.
2. For the rest of the world, including the vast majority of countries
and of the human population, there is less than 1 year s food supply
typically available during the year; for most countries the food duration
is on the order of half a year or less. Furthermore, if the war were to
occur prior to harvest (i.e., when food supplies were at their minimum
levels), most of the stores would last only a matter of weeks to a few
months.
3. Consequently, if food production were disrupted for one or more
growing seasons, there simply would be not enough food to keep most
of the survivors alive. Starvation, and the diseases and societal disruptions
associated with starvation, would account for global declines in the human
population.
An indication of the extreme vulnerability of the Earn s human pop-
ulation to sole reliance on food stores is seen in Figures Sa-c. Figure 5a
shows the current population, as distributed within latitude bands, and the
population distribution expected after a large-scale nuclear war (based on
other analyses involving a severe-case impact on cities). Figure Sb com-
pares the current population with the number of people who could be kept
alive for one year under the assumptions discussed above if food stores
were at their median level at the time of the nuclear war; Figure Sc shows
the same, but for food stores at their minimum levels. These benchmark
calculations make clear the extent of human vulnerabilities on a global
scale.
One other analysis is also noteworthy. Even if there were no impacts
on food production at all, but only direct food and energy imports were
disrupted, many countries would still be severely affected. Japan is the
most striking case (Figure 6), where cessation in food imports would result
in the loss of half the total population in Japan, even if 100 percent of
current agricultural productivity could be maintained and if no nuclear
detonations occurred in the country. In the much more likely situation of
OCR for page 133
NUCLEI F~INE: THE INDIRECT EFFECTS OF NUCLEI Wit 133
(A)
80-71 N
70-61 N
60-51 N
50-41 N
40-31 N
30-21 N
Lat ( ) 20-11 N
10-1 N
O-9 S
10-19 S
20-29 S
30-39'S
40-49 S
50-59 S
(B) .
80-71 N
70-61 N
60-51 N
50-41 N
40-3 1 N
30-21 N
Lat() 20-11 N
10-1 N
O-9 S
10-19 S
20-29 S
30-39 S
40-49 S
50-59 S
(C)
80-7 1 N
70-61 N
60-51 N
50-41 N
40-31 N
30-21 N
Lat ( ) 20-11 N
10-1 N
O-9 S
10-19 S
20-29 S
30-39 S
40-49 S
50-59 S
~ _
__
_
_
1 1 ·
=
S"
l .~
'NNSSx
. .
, ~
~t I I I I
0 200 400 600 800 1000 1200
Population (millions)
FIGURE 5 1982 population (solid bars) versus survivors of a nuclear war (hatched
bars). A: Current population, as distributed within latitude bands, and population
distribution expected after a large-scale nuclear war. B: Current population in
comparison with how many people could be kept alive for one year if food stores
were at their median level at the time of nuclear war. C: Same as in B. except
for food stores at their minimum level. Source: Harwell et al. (1985, pp. 472 and
4801. Reprinted with permission from the Scientific Committee on Problems of
the Environment (SCOPE).
OCR for page 134
134
150
6
~ 50
o
PHYSICAL EFFECTS AND ENVIRONMENTAL CONSEQUENCES
JAPAN
/''~''''''''''''''''''''''''''''''''~
100% of Production + I mports
_ :. ::.: : I:
~ ~ ~ ....... ...
~::~ If: ~::~::~: if:: 100% of Production
150
100
50
o
To
o-
FIGURE 6 Post-nuclear-war chronic phase agricultural effects in Japan. Source:
Harwell et al. (1985, p. 475~. Reprinted with permission from the Scientific
Committee on Problems of the Environment (SCOPE).
food production impacts, such as from energy input disruptions or from
mild climatic alterations, then 25 percent of current grain production could
keep only about 15 percent of the population alive in Japan.
CONCLUSION
The indirect effects of a nuclear war, especially as mediated by dis-
ruption in food availability, could be much more extensive than the direct
effects. Furthermore, this risk is especially severe for noncombatant coun-
tries- for the 4 billion or so humans expected to survive the immediate
period after a nuclear war relatively physically unharmed. Thus, a fun-
damentally different picture of the post-nuclear-war world results, where
a large-scale nuclear war between the United States and the Soviet Union
would probably result in more eventual fatalities in India than in the United
States and the Soviet Union combined, and more people would die on the
African continent than in all of Europe. Rather than reflecting images of
Hiroshima and Nagasaki, a modern nuclear war would, for most of the
people of the world, much more resemble current images of Ethiopia and
the Sudan.
ACKNOWLEDGMENTS
This report represents the findings of the International Council of Sci-
entific Unions' SCOPE-ENUWAR project, which involved the contri
OCR for page 135
NUCLEAR FAMINE: THE INDIRECT EFFECTS OF NUCLEAR WAR 135
buttons of many scientists from all over the world (see Harwell and
Hutchinson, 1985; Pittock et al., 1985~. We especially recognize the
contributions by Wendell P. Cropper, Jr., Cornell University, and Thomas
C. Hutchinson, University of Toronto. We wish to acknowledge He f;-
nancial support provided by the SCOPE-ENUWAR Unit, Essex Univer-
sity, United Kingdom, and by Cornell University, Ithaca, New York.
REFERENCES
Ambio. 1982. Nuclear War: The Aftermath. Special Issue of Ambio Vol. XI(2-3):75-
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Harwell, M. A., and T. C. Hutchinson, with W. P. Cropper, Jr., C. C. Harwell, and H.
D. Grover. 1985. Environmental Consequences of Nuclear War. Volume II. Ecological
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Pittock, A. B., T. P. Ackerman, P. J. Crutzen, M. C. MacCracken, C. S. Shapiro, and
R. P. Turco. 1985. Environmental Consequences of Nuclear War. Volume I. Physical
and Atmospheric Effects. SCOPE 28. Chichester, U.K.: John Wiley & Sons.
Representative terms from entire chapter:
indirect effects
