United States
Environmental Protection
Agency
Off ice of
Research and Development
Washington DC 20460
EPA 600/878-002
January 1978
vvEPA
Results of Research
Related to Stratospheric
Ozone Protection
Report to Congress
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United States Office of
Environmental Protection Research and Development EPA 600/8-78-002
Agency Washington, B.C. 20460 January 1978
RESULTS OF RESEARCH
RELATED TO STRATOSPHERIC
OZONE PROTECTION
REPORT TO CONGRESS
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DISCLAIMER
This report has been reviewed by the Office of Research and Devlopment,
U.S. Environmental Protection Agency, and approved for publication. Mention
of trade names or commercial products does not constitute endorsement or re-
commendation for use.
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PREFACE
This report is submitted to Congress in compliance with Section 153(g)
of the Clean Air Act Amendments of 1977, Public Law 95-95 [PL 95-95]. The
law requires that the Administrator of the Environmental Protection
Agency, as part of the program for ozone protection, shall "not later than
January 1, 1978, and biennially thereafter,. . .report to the appropriate
committees of the House of Representatives and the Senate, the results of
the studies and research conducted under Section 153 and the results of
related research and studies conducted by other Federal agencies." As is
indicated in the Executive Summary, some research was underway prior to
passage of PL 95-95. In September 1977, as part of the response to
Section 153 of PL 95-95, the Agency conducted a multidisciplinary and
multiagency workshop to review research and to provide a basis for further
planning of research. The purpose of the symposium was to provide outputs
to support regulatory decision-making and provide a better basis for
optimum protection of public health and welfare from ozone depletion
caused by human activities.
In order to accelerate and improve the quality and focus of research,
the Agency program on Biological and Climatic Effects Research (BACER)
contracted with SRI International (SRII) for scientific and technical
support. SRI International, as part of the work under that contract,
prepared this initial overview, under the direction of Dr. Alphonse F.
Forziati, Director, and members of the Stratospheric Modification Research
Staff.
ill
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CONTENTS
LIST OF ILLUSTRATIONS iv
LIST OF TABLES iv
I EXECUTIVE SUMMARY 1
A. Introduction 1
B. Findings to Date—An Overview I
C. Future Research Needs 5
1. Human Health 6
2. Nonhuman Biological Systems 6
3. Climate Effects 6
4. Monitoring and Instrumentation 7
5. Integrated Assessment 7
II TECHNICAL DISCUSSION 8
A. Introduction 8
B. Human Health 8
1. Background 8
2. Current Research 9
a. Acquisition and Analysis of Epidemiological
Data on Skin Cancer 9
b. Identification of the Groups Susceptible to
Skin Cancer 11
3. Future Needs 12
C. Nonhuman Biological Systems 12
1. Background 12
2. Current Research 13
3. Future Needs 15
D. Climate Effects 17
1. Background 17
2. Current Research 19
3. Future Needs 22
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II TECHNICAL DISCUSSION (Continued)
E. Monitoring and Instrumentation 25
1. Detectors 25
2. Sources 28
3. Current Research 28
a. Review of Measurement Uncertainties ... 28
b. Robertson-Berger Sunburn Meter Network . . 28
c. Norris Spectroradiometer 29
d. Immersible Spectroradiometer 30
e. Argon Mini-Arc 30
f. BZ Fluorescent Lamp 30
F. Integrated Assessment 31
1. Background 31
2. Current Research 31
a. Social and Economic Effects 31
b. Research to Support Regulatory
Decisions 37
3. Future Needs 37
REFERENCES 40
VI
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ILLUSTRATIONS
1 Effects Resulting from Release of Ozone-Depleting
Substances 2
2 Change in Flow of Weather Systems that Caused the
Anomalous Winter of 1976-77 18
3 One-Dimensional Model Calculations for the Vertical
Distribution of Ozone Change 21
4 World Reserves of Grain as Percent of Total Annual
Consumption, 1961-1976 33
5 World Wheat Yield, 1950-1975 35
6 Variation of Global Mean Surface Air Temperature.
Five-year averages from 1880-1884 to 1965-1969 36
TABLES
1 Human Health Research Needs 13
2 Nonhuman Biological Research Needs 16
3 Climate Research Needs 23
4 UV Monitoring Needs 26
5 Integrated Assessment Needs 39
VI1
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I EXECUTIVE SUMMARY
A. Introduction
The possibility of a need to protect the stratospheric ozone layer
against man-made causes of depletion first arose in connection with emis-
sions from supersonic aircraft. To study such concerns the Climatic
Impact Assessment Program (CIAP) was undertaken by the Department of
Transportation from 1970 to 1974 at the direction of Congress. This was
followed by concern over the possible depletion of ozone due to the release
of chlorofluorocarbons (CFCs). The Federal Committee on Science and
Technology requested the Environmental Protection Agency (EPA) to take
the lead in a Federal program to study this problem, and in 1976 EPA
reprogrammed $4 million of Research and Development funds to support a
multiagency Biological and Climate Effects Research (EAGER) program. In
August 1977, Congress passed PL 95-95, the Clean Air Act Amendments of
1977, which includes a mandate for EPA to undertake and coordinate Federal
Research to ascertain impacts of ozone depletion on public health and
welfare, and human-generated causes of such depletion. This document is
the first report on Federal Research required biennially under
Section 153(g) of PL 95-95.
B. Findings to Date—An Overview
This section summarizes the results of BACER-supported research
and related studies. It does not describe all the relevant research
results obtained by other federal agencies, since Section 154 of the
Clean Air Act requires them to submit separate reports. Reports from
these other federal agencies complement the present document. To the
extent possible, their results are integrated into this summary.
As illustrated in Figure 1, the uncontrolled release of ozone-
depleting substances to the atmosphere has far-reaching implications.
The resulting effects are not limited to the United States, but are
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RELEASE OF
OZONE-DEPLETING
SUBSTANCES
IMPACT ON
STRATOSPHERIC
OZONE
CHANGES IN
TRANSFER OF
RADIANT ENERGY*
IMPACT
ON BIOLOGICAL
SYSTEMS
IMPACT
ON CLIMATE
RESULTING
SOCIAL AND
ECONOMIC IMPACTS
* Includes both ultraviolet radiation (notably UV-B, 290 to 320 nanometers
wavelength), visible, and infrared (IR) radiation.
FIGURE 1 EFFECTS RESULTING FROM RELEASE OF OZONE-DEPLETING SUBSTANCES
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distributed globally. There are many uncertainties and unknowns in each
research area, and concerning the relationships among research areas.
The general objective of the research to date has been to reduce these
uncertainties, probe into certain areas where knowledge is meager, and
quantify ozone-depletion impacts wherever possible.
Recent research suggests that if chorofluorocarbon (CFC) releases
were to continue at the 1975 rate, a stratospheric ozone depletion of
over 10% could occur in three to five decades. This would affect the
transfer of solar energy in the atmosphere. Current capabilities to
assess the impact of such depletion on weather and climate are limited
to approximate predictions of globally averaged temperature decreases.
(The current predicted decrease is less than 0.2°C.) However, ozone
depletion could also have large effects on local and regional weather,
including precipitation. Unfortunately, current lack of information on
this issue limits the ability to make useful predictions.
Since the stratospheric ozone layer shields the earth's atmosphere,
surface, and waters from damaging ultraviolet wavelengths between 290
and 320 nm (UV-B), the estimated ozone depletion will also result in
increases of UV-B dosages to all exposed biological systems. Therefore,
much of the current research has focused on analyzing the effects of
increased UV-B exposures on humans and nonhuman biological systems.
Since humans are not exposed experimentally to controlled dosages
of UV-B, assessments of the effects of UV-B exposure on human health
are largely based on demographic studies using epidemiological data.
The emphasis has been on analyzing skin cancer incidence rates. Relevant
EAGER projects are described in detail in Section II of this report.
The most significant health findings to date are:
• For the population as a whole, the incident of melanoma of the
skin has substantially increased in recent years; for adults
under age 65 an increase in non-melanoma skin cancer has also
occurred.
• Skin cancer incidence of all types is believed to be directly
related to UV-B exposure.
• Some sub-populations (i.e., skin types, ethnic groups, and so
forth) are more susceptible to increases in skin cancer incidence
than are others.
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There is thus a basis for inferring that an increase in UV-B radiation
at the earth's surface resulting from stratospheric ozone depletion could
lead to an increase in the incidence of both melanoma and non-melanoma
skin cancer in certain sections of the population. Current studies are
attempting to quantify or refine the above findings.
Other biological (ecological) systems have been experimentally
exposed to controlled dosages of UV-B. Nevertheless, the problem of
quantifiying these biological effects is enormous. Only a relatively few
major plant and animal groups, primarily higher plants, have been tested.
In spite of this limitation, EAGER and previous research leads to the
following conclusions:
• Small increases of UV-B appear to inhibit photosynthesis in
some terrestrial and aquatic plants and at least some nitrogen
fixing mechanisms.
• Plant species possess the capability for some repair of UV-B
damage when exposed to full sunlight in the visible portion of
the spectrum but this repair does not prevent significant reduc-
tions in the yields of sensitive species.
0 Shifts in the composition of both aquatic and terrestial plant
and animal communities are probable, and some of these shifts
appear likely to significantly damage commercial fisheries.
It can thus be stated that an increase of UV-B radiation at the
earth's surface resulting from stratospheric ozone depletion would
probably have significant ecological impacts. However, there is a lack
of means to assess and predict sensitivity of various ecological systems
to increased UV-B radiation. Further effort is necessary to quantify
such sensitivity before social and economic impacts can be evaluated.
The effects of ozone depletion summarized above have many indirect
social and economic consequences. The specification of these consequences
has been limited by the availability of data on the nature and magnitude
of the primary effects (on humans, other biological systems, and climate).
While monetary costs can only be approximated due to the uncertainties,
it is generally acknowledged that over a few decades these costs (e.g.,
health care, and agricultural losses) could amount to hundreds of billions
of dollars. Hence, from the monetary point of view alone, there is a
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strong motivation to investigate regulatory alternatives. Section II
contains a more detailed discussion of these social and economic impacts.
Improved instrumentation and monitoring are vital to research on ozone-
depletion impacts. A significant portion of the funds available for this
research has been spent on development of (1) improved UV-B sources and
instrumentation, (2) additional UV-B monitoring, and (3) analysis of the
resulting data base. Under Item 1 above, the Norris spectroradiometer was
developed for biological effects research. Also, a submersible
spectroradiometer is being evaluated to study the potential effects of UV-B
radiation on the aquatic environment. In an effort to improve the accuracy
of a variety of UV-B sources and detectors, the National Bureau of
Standards (NBS) has established a quality-assurance procedure that will
ultimately reduce field measurement errors to less than 10%. (Currently
these range as high as 457». )
Additional UV-B monitoring (Item 2) was undertaken by the National
Oceanic and Atmospheric Administration (NOAA) at the key epidemic logical
locations, as identified in the National Cancer Institute (NCI) skin cancer
studies. 'Under Item 3, analysis of existing NOAA data has resulted in a
verification that the ratio between UV-B enhancement and ozone depletion is
very close to the theoretically predicted value of 2 (i.e., a 2% increase
in UV-B for every 17<> decrease in ozone).
Again, it is emphasized that more data and research are needed to
reduce the uncertainties associated with estimation of impacts caused by
ozone depletion. Section I-C addresses needs for future developments that
will lead to an improved data base and more accurate appraisal of the
impacts1 involved.
C. Future Research Needs
A potential for significant adverse environmental effects has been
suggested by research accomplished to date. Examples are skin cancer
incidence, effects on larvae of commercially important fishes, marine
organisms such as phytoplankton and zooplankton, and certain plants used
as food. More data are needed in all areas (i.e., human health, other
biological/ecological systems, climate monitoring, economics, and social
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issues). The general research requirements are outlined here. Section II
contains a more detailed description of these requirements.
Research needs are separated into short-term and long-term programs.
Short-term programs are those that will return substantial quantitative
knowledge within a one- to two-year period. The longer-term research
program objectives are to broaden the base of knowledge and further reduce
uncertainties and to identify and quantify the direct and indirect
effects of ozone depletion on human health, and ecological, geophysical
and socio-economic systems.
1. Human Health
Short-term benefits can be derived from continuing (1) the
analysis of existing morbidity and mortality data to quantify the rela-
tionship between the ozone depletion and skin cancer, and (2) the opera-
tion of the NOAA Robertson-Berger Network at the 10 key locations for
which there are epidemiological data. Other projects with longer-term
payoffs include expanding the data base for non-melanoma skin cancers,
characterizing high-risk individuals, and acquiring basic information on
»
skin cancer induction through studies on animals.
2. Nonhuman Biological Systems
The most pressing research needs in nonhuman biology are the
development of validated predictors of UV-B sensitivity; the replication
of eye-cancer studies using smaller, less expensive laboratory animals;
and extension of the analysis of ways in which organisms are affected
by UV-B and photosynthetically active radiation. Equally important but
more time-consuming needs are the expansion of experimental studies of
the effects of UV-B on interactions among plants, animals, and microbes;
and studies to verify preliminary data on pollinators.
3. Climate Effects
Because of the wide range of activities and the large number
of scientists conducting climate-related research, a yearly workshop
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concerned with the role of stratospheric ozone in weather and climate
would be highly beneficial. The workshop would help promote a high
level of information exchange and thus establish the framework for future
research. Other programs that would produce results in the near term
include (1) continuation of the statistical analysis of existing clima-
tological data, and (2) the evaluation of the effect of increased UV-B
on photochemical smog. Longer-term needs call for the improvement in
climate and general circulation models, and the measurement of atmospheric
trace substances (including aerosols) that influence the climate.
4. Monitoring and Instrumentation
Monitoring of UV-B radiation (or related parameters) is essen-
tial for establishing a data base to support studies on the effects of
ozone depletion. The Robertson-Berger network should be continued, and
should result in short-term benefits in skin cancer studies (as mentioned
in Section I-C-1, above), and other biological/ecological studies as well.
The NBS quality-assurance program should be continued, to ensure that
measurements are supported by frequent calibrations against known stand-
ards. Other measures with long-term benefits include development of a
spectroradiometer network, continued tests on the immersible spectro-
radiometer, and development of personal dosimeters.
5. Integrated Assessment
An integrated assessment of ozone-depletion effects, resulting
costs, and social consequences must be undertaken to provide suitable
information on which to base regulations. Basically, three programs are
needed for this purpose. The first, an interdisciplinary workshop, would
provide a forum in which economists and other scientists could exchange
information on the costs and risks of control versus non-control. The
second need is an optimum control model, which provides the framework
for quantitative assessments that are essential in the regulatory process.
The third need is for an objective method by which future research can be
given priorities. Ideally, the method will help identify what new in-
formation will contribute most to the regulatory decision process.
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II TECHNICAL DISCUSSION
A. Introduction
This section treats the background, current research areas, and
future needs in more detail than the Executive Summary. The findings
are based on research to date for several projects that are still in
progress. Therefore, much of this discussion relies on interim results.
B. Human Health
1. Background
Even before the institution of the BACER program, a clear re-
lationship between sunlight exposure and skin cancer other than melanomas
was commonly accepted. It was known that there was an inverse relation-
ship between these cancers and latitude, that the high-risk individuals
were those who spent a great deal of time out of doors, such as sailors
and farmers, and that blacks were a low-risk group. Because albino blacks
were known to be at high risk, a genetic explanation other than pigmenta-
tion was ruled out.
There was also highly suggestive evidence that sunlight was a
cause of malignant melanoma. Mortality and incidence rates of malignant
melanoma had been found to be higher with decreasing latitude (Lancaster,
1956; Lee and Merrill, 1970; Cutler and Young, 1975), and blacks had been
found to be at low risk for melanoma (Lancet Editorial, 1971).
Several mathematical models had been proposed to predict the
potential effect of ozone reduction on skin cancer incidence other than
melanoma (Urbach et al., 1974). These models were based on data from
the National Cancer Surveys. Early models predicted that a 1% decrease
in ozone would result in a 2% increase in incidence rates for these
cancers. However, later studies suggest a 4% increase in cancer incidence
rates for a 1% decrease in ozone.
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2. Current Research
a. Acquisition and Analysis of Epidemiological Data on
Skin Cancer
EAGER funds support three projects currently under way in
this area. The largest project is being conducted by the National Cancer
Institute. It consists of reviewing all newly diagnosed skin cancers
other than malignant melanomas within several geographically defined
populations. These populations are participating in the SEER (Surveil-
lance, Epidemiology, and End Results) program. These populations allow
direct comparisons between geographic latitude and age-adjusted incidence
rate for skin cancer other than melanoma. To the extent possible, NCI
will also try to correlate cancer incidence rates with more direct mea-
surements of UV-B flux. These data are not routinely available from
existing sources such as cancer registries as are corresponding data for
malignant melanomas; this is probably because skin cancers other than
malignant melanomas are usually treated in physicians' offices or out-
patient clinics rather than hospitals.
A second project is being conducted at the Department of
Statistics of the University of California at Berkeley. In this approach,
UV-B exposure data are correlated with existing data on skin cancers,
including data obtained at locations selected for the Health and Nutri-
tion Examination Survey (HANES), the National Ambulatory Medical Care
Survey, and the Survey of Discharges from Short Stay Hospitals—all sur-
veys run by the National Center for Health Statistics. Considerable
meteorological data including cloud cover information are being collected
for each of the 65 HANES locations and for other survey locations as
well. The investigators plan to correlate the meteorologic indicators
of UV-B exposure with the skin cancer rates to try to estimate more
exactly the increases in skin cancers resulting from increases in UV-B
exposure.
The third project, being conducted at the Department of
Epidemiology at the University of Washington, consists of a detailed
analysis of existing data sources for skin cancer. One set is U.S.
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mortality data on all skin cancer, both melanoma and non-melanoma, that
are available from 1931 to 1974. Beginning with the eighth revision of
the International Classification of Diseases in 1968, the melanomas can
be analyzed separately from the non-melanomas. Before 1968, the assump-
tion has been made that 95% of the deaths from skin cancer between the
ages of 20 and 64 were caused by melanomas. Most of the work has in-
volved dealing with trends only for individuals between the ages of 20
and 64.
The purpose of this study at the University of Washington
is to take the long-standing existing mortality data that are routinely
reported, and break these mortality rate trends over time into various
components, with the hope that models can then be constructed from which
future predictions can be made and compared with actual trends. This
would allow more precise correlation of ultraviolet flux with the inci-
dence rate for malignant melanoma and for other skin cancers. Thus far
this analysis of U.S. mortality data has identified different components
of the overall trend. The overall skin cancer mortality rates have shown
a decrease since 1931. However, this decrease is confined to ages 65
and over; younger ages have shown an increase over time. The increasing
mortality rate in the younger age groups is due to an increasing incidence
rate for malignant melanoma. This increasing rate has been documented
elsewhere and has been shown to be primarily occurring as a result of a
change in risks over generations, with people born later having higher
rates at the same ages than people born earlier. This is known techni-
cally as a birth cohort effect. However, the rate of increase of mor-
tality with age is considerably lower at older ages for the later-born
cohort than it was for the same ages in those born earlier. If the slope
of these curves for each age is plotted, it is clear that this decline
in slope is not a function of age. However, when the slope data are
rearranged versus time, it is clear that there has been a general decline
in the rate of increases of mortality with age. Mortality rates for the
rest of the century have been projected based on a continuation of these
trends in birth cohort effects and the change of slope in mortality with
age.
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To check on the possibility that the decline in the rate
of increase of mortality rates with age could be the result of increased
early recognition and treatment of these cancers, the Connecticut Cancer
Registry incidence data were studied and no evidence was found of a de-
cline in the rate of increase in incidence with age. Apparently, there
was a steady improvement in early recognition and treatment of melanomas,
and in fact, the case fatality rate for malignant melanoma has been de-
creasing. It therefore appears that the overall decreasing trend in skin
cancer mortality rates is a result of decreased case fatality rate for
malignant melanoma in spite of an increased incidence rate for skin cancer
*
in general, which is a result of a birth cohort effect reaching a peak in
individuals born about 1931.
b. Identification of the Groups Susceptible to Skin Cancer
Two projects that were funded in FY 1977 were designed to
identify the sub-population most susceptible to skin cancer. One project
was led by the National Cancer Institute. At present, NCI is determining
whether a case control study of skin cancers other than melanoma can be
carried out by telephone survey alone or by a mail questionnaire in addi-
tion to a telephone survey. The study is being pilot-tested in the
Minneapolis-St. Paul SMSA* using skin cancer cases documented in the Third
National Cancer Survey. Among the factors being investigated are skin
complexion, number of hours spent outdoors, clothing habits, frequency
of sunbathing, use of suntan oil and other sun screens, ease of tanning,
ease of burning, use of sun lamps, chemical exposure history, skin con-
ditions (such as acne, oily skin, dry skin, moles, freckles, psoriasis,
warts, hair loss, and hives), and the eye and hair color. The investi-
gators intend to match cases and controls for age, sex, and race.
The second project is being carried out by The Department
of Dermatology at Massachusetts General Hospital. This study is intended
to be a case control study of malignant melanoma. The controls will be
Standard metropolitan statistical area,
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matched to cases according to age and sex within the same neighborhood
so that their socioeconomic status will presumably be similar. The in-
vestigative team plans to obtain histories of exposure to sunlight accord-
ing to the time in the individual's life, such as childhood, first job or
college, marriage, and other life periods, and not according to specific
ages. The individuals will also be asked about their recreation patterns
and exposure to chemicals. The investigators are interested in contrast-
ing the risk of disease for relatively brief but intense exposures to
sunlight with the risk for low-level exposures continued over a long
period of time, which might result in the same total dose. These risks
will then be compared with those for relatively non-exposed individuals.
The pilot study will explore behavioral attitudes of cases and controls
toward sunlight exposure. Further, it will obtain information on physi-
cal characteristics such as skin, eye, and hair color, that might be
important variables.
3. Future Needs
Future needs are summarized in Table 1. Studies on melanoma
skin cancer incidence can provide meaningful results in the near term
because the data base is adequate (though in need of improvement). The
same is not true for the non-melanoma skin cancer data base. Therefore,
this data base must be expanded—a time-consuming process with long-term
payoffs. Hopefully, studies on animals can lead to a more basic under-
standing of the mechanisms involved, both for melanoma and non-melanoma
skin cancers.
C. Nonhuman Biological Systems
1. Background
The biological effects of UV-B (290 to 320 nm radiation) re-
ceived little attention prior to the EAGER and CIAP programs. The major
achievements before these programs started were a preliminary, qualita-
tive assessment of the effects of UV-B and the evolution of generally
accepted methods of experimentation using commercially available lamps
and filters.
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Table 1
HUMAN HEALTH RESEARCH NEEDS
Research Needed
Benefits
Epldemiological Data Analysis.
Continue the analysis of existing
morbidity and mortality data to
quantify the relationship between
ozone depletion and skin cancer.
UV Radiation Monitoring. Ensure
that UV flux measurements are being
made in locations where epidemic-
logic data are being collected.
Nonmelanoma Data. Collect data in
order to calculate incidence rates
for non-melanoma skin cancer in de-
fined geographic areas.
High-Risk Groups. Characterize
high-risk individuals by conducting
case-control studies of both mela-
noma and skin cancers other than
melanoma.
Animal Research. Conduct studies on
animals to acquire basic information
on the mechanism of skin cancer
induction.
Short term
Short term
Long term
Long term
Long term
Short-term EAGER and associated research by other agencies and
institutions has developed better experimental hardware, extended the
qualitative assessments of UV-B data, and begun reliable quantification
of effects.
2. Current Research
Short-term EAGER research in nonhuman biology has focused to
date on effects of UV-B radiation on crop plants, primarily as measured
in controlled environments. Explorations have been started on the ef-
fects of such radiation on agriculturally important crops, insect pests,
nitrogen fixation, gas exchange rates in field and horticultural crops
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under field conditions, eye cancer in cattle, growth impairment in forest
tree seedlings, plant-pathogen interactions, and effects on commercial
fisheries. Research sponsored by other agencies has focused upon effects
on plant and animal communities.
As a result of the research funded by short-term EAGER, and
related NASA programs, it can confidently be said that increased UV-B
irradiation will cause adverse impacts, but the magnitude of these impacts
cannot reliably be estimated. Results to date have demonstrated con-
siderable variation among species, and among cultivars within species;
however, no recognizable pattern of interspecific variation has been
noted. The most common responses in crop plants are symptoms of reduced
growth or delayed maturation, such as reductions in leaf area, height, or
weight, and delays in germination. These effects imply reduced crop
yields, increased disease susceptibility, and possibly both increases and
decreases in the need for pesticide usage, depending on the crop. Impli-
cations for fertilizer usage are unclear, since the data base is meager.
However, the preliminary findings suggest that some nitrogen fixing
mechanisms in algae will be impaired at the increased levels of UV-B
irradiation that may occur. Impacts on animals are less amenable to
generalization, but preliminary results indicate that increases in UB-V
radiation cause reductions in insect lifespan and numbers of offspring
per surviving adult, and in delay of development; eye damage in cattle;
and the formation of brain and retinal lesions in fishes and aquatic
invertebrates. At least some of the aquatic species and perhaps some of
the higher plant species studied appear to be at or very near their limits
of tolerance of UV-B at the present levels of UV-B irradiation, and thus
would be adversely affected by further increases. However, much more
precise measurements of natural variations of UV-B incidence are needed
to verify this preliminary observation.
In sum, the variation among species in sensitivity to UV-B,
and the extreme sensitivity of some species studied, imply that shifts
in composition of natural plant and animal communities will occur if UV-B
irradiation increases, and perhaps changes in agricultural practices
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may be expected. However, quantitative predictions of the size and sig-
nificance of these changes are not feasible with the current knowledge.
3. Future Needs
To quantify biological, social, and economic impacts, a better
connection must be developed between laboratory and field experiments to
permit wider extrapolation. For some organisms, such as mammals other
than beef cattle, the data base must be extended (see Table 2). Moreover,
there remains a pressing need for insight into the damage resulting from
UV-B, and possible subsequent repair in the presence of photosynthetically
active wavelengths of light.
Acquisition of at least a statistically reliable empirical
analysis of the interaction between UV-B, photosynthetically active
radiation, and photorepair is needed to permit use of the existing data
base in economic and ecological analysis, and should be given the highest
priority. While crop losses can be directly measured in field experi-
ments, the preliminary results of the EAGER studies suggest that effects
will be at the limit of experimental detection in field experiments even
under favorable circumstances. Hence, given the variability of weather
from year to year, several years of field experimentation would be re-
quired to obtain a statistically defensible estimate of the damage to be
expected from increased UV-B irradiation.
Roughly the same amount of time is needed to expand the data
concerning effects on aquatic organisms. The existing data base is
small, but indicative of severe impacts on those species whose larval or
other stages remain near the water surface during daylight hours. While
the preliminary aquatic experiments, like their terrestrial counterparts,
are biased toward overestimation of the hazards, these biases probably
are small.
Second but high priority should be given to extension of the
data base on effects on animals, particularly on mammals, birds, and
aquatic organisms, since the economic and ecological implications of
adverse effects on these groups are very great.
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Table 2
NONHUMAN BIOLOGICAL RESEARCH NEEDS
Research Need
Benefit
• Photorepair. Extend analyses of the interaction be-
tween UV-B and photorepair, validating the results
with field experiments to facilitate the extrapola-
tion of existing growth chamber and greenhouse data
to field conditions (which is needed for economic
assessments).
• Eye-Cancer Studies. Replicate the eye-cancer
studies on Herefords using smaller, less expensive
laboratory animals (mammalian and avian species), and
simultaneously look for adverse effects other than
cancer.
• UV-B Predictors. Explore potential of predictors of
sensitivity to ionizing radiation for use as predic-
tors of UV-B effects, and pursue less circuitous
indicators as concepts develop.
• Interactions among Species. Replicate and expand ex-
perimental studies of the effects of UV-B on inter-
actions between plants, animals, and microbial
pathogens or symbionts in both terrestrial and aquatic
experiments. Particular emphasis should be given to
expansion of the data base on zooplankton and fish
larvae and N2~fixing organisms to confirm and extend
the available estimates of the magnitudes of the
effects of UV-B.
• Physiological Responses. Extend the studies of the
physiological responses of insects to investigations
of impacts on behavioral parameters, particularly the
ability of bees to pollinate crops.
Short term
Short term
Short term
Long term
Long term
Since the connection between ionizing radiation and health
effects is fairly well known, exploration of the possibility of a cor-
relation between sensitivity to UV-B and sensitivity to ionizing radia-
tion warrants a small but immediate effort. The potential payoff could
be very high if it led to extrapolation of the data base to unstudied
species.
16
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The last two items in Table 2 are comparable to the first three
in importance, but are unlikely to quickly yield results useful in the
regulatory process.
D. Climate Effects
1. Background
Stratospheric ozone depletion would affect the heat balance of
the atmosphere by modifying the transfer of radiant energy. The effect,
which varies strongly with wavelength, extends across the spectrum includ-
ing all the UV, through the visible, and into the infrared. As a result,
changes would occur in the vertical distribution of temperature and in
the surface temperature. In turn this could lead to perturbation of
current weather patterns and to local changes in precipitation and tem-
perature .
It is important to recognize that the weather changes due to
ozone depletion that are of greatest concern are regional and seasonal
changes rather than changes in the global, annual averages, and this is
particularly so in the case of precipitation incidence (Geisler 1977;
Strommen, 1977). Thus, very serious impacts could occur without being
reflected by large changes in such indicators as globally averaged annual
temperature.
These points are illustrated by several examples in Section
II-F. One of the examples is the anomalous winter of 1976-77, during
which the eastern United States suffered record cold and heavy snowfall
(Wagner, 1977a, b; Dickson, 1977a) while California experienced a record
drought (Dickson, 1977b). It is now generally recognized that the severe
weather of the 1976-77 winter was associated with a change in the wave-
like flow of weather systems from their normal pattern to the one shown
in Figure 2. The 1976-77 pattern diverted normal rainbearing storms
away from the western United States (causing the severe drought there)
and brought Canadian and Arctic weather systems southward into the east-
ern United States. Yet in spite of the resulting dramatic impacts on
17
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FIGURE 2 CHANGE IN FLOW OF WEATHER SYSTEMS
THAT CAUSED ANOMALOUS WINTER OF
1976-1977
18
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U.S. weather, the weather anomalies of winter 1976-77 had little, if any,
impact on global average surface temperature (Geisler, 1977) .
The wavelike flow of weather systems shown in Figure 2 results
from many factors but is affected by latitudinal temperature differences
and the stratospheric temperature profile, which are in turn affected by
changes in the height, amount, and latitudinal distribution of strato-
spheric ozone. Hence, the most important climatic effect of stratospheric
ozone depletion could very well be to contribute to changes in the current
"normal" pattern of these wavelike weather flows. A complete understand-
ing of the climatic effects of ozone depletion thus requires an ability
to predict ozone effects on these atmospheric planetary waves.
In order to be able to assess the impact of perturbations of
this type it is necessary to have a methodology capable of linking changes
in the ozone layer to such changes in atmospheric dynamics, and their
resulting changes in temperature and precipitation on a regional scale.
This is beyond current capability which, when considering ozone effects,
can only provide approximate predictions of globally averaged surface
temperatures (with some indication of latitudinal dependence). It is
important to emphasize, however, that the simple models used to make such
average temperature predictions do serve a valuable purpose—namely, to
identify potentially important climate change mechanisms and to study
climatic feedback and other physical processes. Hence, there is a need
to continue to refine these simple models while work continues on improv-
ing the predictive capabilities of the more complete and detailed models
of atmospheric circulation.
It is important to be able to determine whether significant
change is taking place before an irreversible or otherwise deleterious
trend is established. Unfortunately, because the natural variability in
climate is so large, small but significant trends are easily masked.
2. Current Research
Short-term EAGER funds to investigate possible ozone-induced
climatic changes were allocated to three areas: (1) a workshop held at
19
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the National Center for Atmospheric Research (NCAR) in June 1977; (2)
NOAA studies of regional differences and the correlation of impacts with
regional climate statistics; and (3) climatic presentations and discus-
sions at the EAGER workshop held at the University of Maryland in
September 1977.
The NCAR Workshop participants repeatedly emphasized the im-
portance of precipitation and regional changes. The workshop section
on observations pointed out the extreme difficulty of detecting small
trends, both because of natural variability and because of sampling
problems. The section on general circulation models agreed that the
importance of regionality and precipitation established an ultimate need
for three-dimensional global circulation models that can predict ozone
effects on planetary waves, blocking, and storm tracks. This capability
does not exist now, and some evidence indicates that it may be extremely
difficult ever to develop such a capability. In any case, at least a
decade of sustained research will be required to develop a better under-
standing of the problem and of possibilities for attaining solutions.
The NCAR Workshop sections on simple climate models and the
stratosphere reviewed current predictions of ozone depletion and result-
ant temperature changes. Current models predict an ozone column depletion
of over 10% could occur within three to five decades if CFG releases
continue at the 1975 rate (for details see NASA, 1977, and Hudson, 1977).
The predicted depletion is largest above the ozone peak, as shown in
Figure 3. (Ozone concentration typically peaks between 16 and 30 km.)
One-dimensional radiative-convective models predict that a vertically
uniform 10% decrease in ozone content will decrease global average sur-
face temperature by 0.1 to 0.15°C. However, they also show that a lower-
ing of the ozone peak, which is also predicted, would tend to increase
surface temperatures. Hence, the two effects appear to be mutually
offsetting relative to changes in surface temperature.
The predicted temperature effects are approximate because some
potentially significant feedbacks have not yet been included in the
models. Nevertheless,it does appear that the ozone-induced change in
global average surface temperatures would be less than the decrease of
20
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50
40
Z 30
O
X
O
in
O
CO
< 20
H
O
Ul
10
-50
-40 -30 -20
OZONE CHANGE — percent
-10
10
FIGURE 3 ONE-DIMENSIONAL MODEL CALCULATIONS FOR THE VERTICAL
DISTRIBUTION OF OZONE CHANGE. Source: Geisler (1977).
21
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about 0.3°C observed between 1944 and 1970 (see Section II-F, Figure 6).
This reemphasizes the fact that the most important climatic effect in-
duced by ozone depletion would probably be regional changes caused by
modification of planetary wave behavior. The possibility of such changes
must be taken seriously, since the ozone changes shown in Figure 3 would
substantially alter the stratospheric temperature profile, which could
in turn alter the stratospheric reflection and transmission coefficients
for planetary waves. More importantly, latitudinal change in the tempera-
ture of the troposphere resulting from ozone depletion could alter the
equator-to-pole heat flow—another important determinant of weather system
motion. However, as stated above, there is currently no capability for
reliably predicting these regional and precipitation effects that would
result.
Because of the difficulties in numerically modeling regional
climate effects, the NOAA-monitored studies have focused on paleoclima-
tological studies of what regional climates and impacts were like during
previous periods of global atmosphere cooling or warming. These studies
revealed marked spatial variations in regional temperature and precipita-
tion during previous periods of overall hemispheric cooling or warming,
and showed that very large precipitation changes often accompanied rather
modest temperature changes (Webb, 1977, Wigley, 1977). Although these
Studies did not reveal preferred (i.e., repetitive) geographical patterns
of climatic change that accompany general planetary warmings or coolings,
they did establish powerful analytical techniques, which, when applied
to larger data bases, might reveal such patterns. Uncovering such pat-
terns could make it possible to anticipate the regional climatic changes
associated with a future increase of atmospheric pollutants before
advanced climate models are able to assess the. situation theoretically
(Sprigg, 1977).
3. Future Needs
Recommended climate research needs are summarized in Table 3.
The first need, a climate workshop focused principally on stratospheric
ozone-depletion effects, is warranted to minimize the potential redundancy
22
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Table 3
CLIMATE RESEARCH NEEDS
Research Need
Benefits
Climate Workshop. Organize and convene workshop on
anthropogenic climate modification. Invite national
and international experts in the field of climate
modeling and monitoring. Assess the state of the art
of potential global and regional climatic impact of
anthropogenic atmospheric perturbations, such as ozone
depletion, increasing burden of infrared absorbing
species (CFC, C02, N20, H20), and aerosol particles.
Statistical Analyses. Apply judicious statistical
methods to existing climatological data, both to
detect possible anthropogenic trends in climate vari-
ables and to design better monitoring systems.
UV-B and Smog. Study effects on urban air pollution
caused by an increase in UV-B induced by stratospheric
ozone depletion.
Climate Models. Assess by means of theoretical model-
ing, using an empirical data base, the climatic
changes that may occur as a consequence of anthropo-
genic activity. The primary concern will be the
alteration to the radiation budget by ozone removal,
aerosol formation, and introduction into the atmos-
phere of other infrared absorbing/emitting species.
Include latitude dependence and feedback by ice albedo
and clouds.
Trace Substance Monitoring. Monitor atmospheric trace
substances (including aerosols) that play a central
role in determining anthropogenic influence on climate.'
General Circulation Models. Improve general circula-
tion models to simulate the effects of ozone-depletion-
induced changes in tropospheric temperature,
stratospheric temperature, and winds on planetary waves
and storm tracks. Improve cloud parameterization to
permit inclusion of cloud feedback effects. '
Short term
Short term
Short term
Long term
Long term
Long term
Research supported primarily by other agencies as specified by Section
154 of PL 95-95. EPA may support essential efforts for which other
funding sources are discontinued.
"^Research supported by other agencies as specified by Section 154 of
PL 95-95.
23
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in effort of the groups active in climate research. Also, climate
modelers should benefit from added insight through information exchange.
Changes in the surface incidence of UV-B radiation resulting from deple-
tion of the stratospheric ozone layer also warrant special attention in
the context of atmospheric conditions in connection with smog formation.
In urban atmospheres UV-B is a critical factor in the photo-chemical
transformation processes causing smog. The remaining needs in Table 3
represent continuations of existing research efforts.
24
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E. Monitoring and Instrumentation
The instantaneous incidence of UV radiation at the surface is of
very low intensity and varies markedly with wavelength. It is thus dif-
ficult to measure or to discern its variations. Useful evaluation of
the amounts and effects of UV radiation requires (1) the development (or
adaptation) of standardized instruments and methods for measuring and
producing UV, (2) close collaboration between instrument builders and
users, and (3) frequent cross-calibrations of both laboratory and moni-
toring equipment. The specific needs for UV detectors and sources, both
in long-term monitoring and experimental studies, are summarized in Table
4 and described below.
1. Detectors
For both monitoring and experimental purposes there is a need
for spectrally resolved measurements of UV radiation in the 290 to 320
nm range* with radiometric accuracy of about 10% and wavelength resolution
of 10 nm or better. For monitoring purposes there is a need for long-
term (at least several-year) measurements at enough locations to yield
reliable means and trends for specific regions (including the oceans) and
latitude bands. Prior to EAGER there was virtually no such information
available in the U.S., although a CIAP-initiated program had begun to
provide regional monitoring of total (spectrally integrated) UV-B radia-
tion, weighted according to the human sunburn spectrum (i.e.ferythemally
weighted). Whereas these total, weighted measurements have yielded vastly
more information than that available prior to CIAP, they do not provide
the spectral information required to determine the effect of UV-B on
processes with action spectra other than those that contribute to sunburn.
(The action spectra for skin cancer and for plant damage are currently
*
The UV-B region spans 280 to 320 nm, but at the earth's surface the
amount of radiation at wavelengths shorter than 290 nm is negligible
compared to the amounts between 290 and 320 nm, so that coverage of
this latter band is adequate.
25
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Table 4
UV MONITORING NEEDS
Research Need
Benefits
• Rad iome ter Ne; twork. Continue the R-B network
one year to yield 5-year data record. Correlate
data with biological, epidemiological, and
agricultural effects. Augment with spectro-
radiometers.
• Standardization. Standardize all UV-B effects
studies by requiring a regimen of frequent
cross-calibration, using specific sources and
procedures. Publish all measured irradiances
and dosages in standard energy density units
(e.g., W/m /nm; J/m^/nm).
• Spectroradiometer Network. Continue develop-
ment of low-cost, portable, automated,
spectrally resolved UV-B detectors. Deploy at
appropriate locations. Intercalibrate the NOAA
Modified Dobson Spectrophotometer, the
Robertson-Berger meter, and the Norris Spectro-
meter.
• Immersible Spectroradiometer. Continue tests
and characterization of the immersible Spectro-
radiometer .
• Personal Dosimeters. Develop and test personal
dosimeters.
Short term
Short term
Short term
Long term
Long term
26
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unknown.) It is this difference in action spectra for different biological
effects that creates the need for spectrally resolved measurements. It is
essential that spectrally resolved measurements, without weighting, be made
and recorded, so that biological effects with action spectra different from
that for erythema can be derived from the data base.
To permit the essential comparisons among different measurements,
radiometers must satisfy the following criteria. They must provide output
2
in internationally accepted physical units (e.g., W/m /nm), be easy to
calibrate, have little long-term or temperature-dependent drift in either
wavelength or radiometric calibration, and have cosine response accurate
to 10% or better. (Cosine response refers to the instrument's ability to
compensate for variations in the incident angle of radiation.) Instru-
ments used for monitoring purposes should be especially durable, and
simple for a non-specialist to clean, maintain, calibrate, and operate.
For laboratory and growth-chamber studies, durability and simplicity are
not as important as finer spectral resolution (than the 10 nm mentioned
above) and compactness of the sensor unit.
Because of the great importance of UV-B effects on marine
ecosystems (see Section II-C), submersible spectroradiometers with char-
acteristics similar to those described above must be developed to permit
measurements of UV-B attenuation in the aquatic environment. There is
also a need for personal UV-B dosimeters that could be unobtrusively
worn in studies to ascertain the effects of lifestyle on personal UV-B
exposure.
There is also a need to improve current ozone-monitoring capa-
bilities, both to permit early detection of significant trends and to
refine relationships between ozone reductions and measured UV-B increases.
It is important to note that improvement in current ozone monitoring
capabilities could be achieved both through improved analysis techniques
for existing instruments and data bases (for example, the satellite UV-B
data), and through improved instrumentation and calibration procedures.
27
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2. Sources
Stable, reproducible, and convenient sources are required for
use both as solar simulators in biological studies and as references for
instrumentation calibration. In the latter application it is especially
important to provide a precise wavelength reference (e.g., a narrow spec-
tral line), since wavelength uncertainty is the major source of radio-
metric error in field spectroradiometric UV-B measurements. (This
uncertainty results from the very strong dependence of intensity on wave-
length near 300 nm; for example, a wavelength error of 0.1 nm leads to
a radiometric error of 10% to 15% in this spectral interval. For this
reason NBS recommends performing a wavelength calibration before each
spectral measurement. See, for example, NBS, 1977.)
3. Current Research
a. Review of Measurement Uncertainties
EAGER funds supported a review by NBS of the accuracies
currently achievable in laboratory and field UV-B measurements (NBS, 1977;
Kessler, 1977). The various sources of error were identified and evalu-
ated in terms of their contribution to overall measurement uncertainty.
It was concluded that, because of the strong dependence of UV-B spectral
irradiance on wavelength, wavelength uncertainties are the largest source
of radiometric error in typical field measurements. Hence, a check of
wavelength calibration before each measurement is recommended. Typical
state-of-the-art measurement errors were shown to range from 3% to 10%
in the laboratory and from 10% to 45% in the field. Progress in reducing
errors has been rapid in the past year and reductions by a factor of
three to five seem probable within the next five years, provided that
vigorous support is continued. Specific recommendations were made for
instrument specifications that would reduce field measurement uncertainty
to 10% or less.
b. Robertson-Berger Sunburn Meter Network
A portion of the short-term BACER budget was devoted to
continuing measurements and analysis in the primary U.S. UV-B monitoring
28
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effort, involving a network of Robertson-Berger (R-B) sunburn meters
(Machta and Hass, 1977). These instruments, first built in the spring
of 1973, measure a weighted integral of UV radiation, with the weighting
designed to approximate the erythemal action spectrum (Urbach et al. ,
1974). They have a cosine response that is accurate to within 10%, and
a sensitivity reproducibility of +5%, and provide an automatic output
each one-half hour. The output is not in energy-density units, but rather
in "counts." However, the integral outputs of all R-B meters are matched
to within +5% at the time of construction, and their relative spectral
response is tested by using a double monochromator in the laboratory.
A conversion factor from "counts" to energy density has been derived by
comparing data measured by R-B meters and collocated Modified Dobson
Spectrophotometers (MDSs—units specially modified by NOAA with a mask
to match the erythemal response). The R-B and MDS measurements were
highly correlated*/ suggesting that any differences in spectral response
between the R-B and MDS instruments are of little importance in atmos-
pheric monitoring.
By the end of 1977, four years of UV-B data will have been
acquired with the R-B network. The primary results achieved during the
period of EAGER funding were: (1) a refined determination showing that
the "amplification factor"—i.e., the ratio of relative UV enhancement
to relative ozone depletion—is very close to the theoretically predicted
value of 2 (though somewhat dependent on sun angle, turbidity, and ozone
amount); and (2) derivation of a simple regression equation relating
annual erythemally-weighted UV-B dosage in the U.S. to latitude and
cloudiness of location.
c. Norris Spectroradiometer
With the aid of EAGER funding, K. H. Norris of the Depart-
ment of Agriculture (USDA), has developed a UV (250 to 370 nm) spectre-
radiometer that satisfies nearly all of the criteria stated in Section
II-E-1 (Norris and Rowan, 1977). It uses a teflon bubble entrance window
*Correlation coefficient of 0.95.
29
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to achieve cosine response accurate to within +10%, a monochromator to
achieve wavelength resolution of 2 nm, and a linked photomultiplier detec-
tor, logarithmic amplifier, digital voltmeter, and programmable calculator
to achieve flexible, automatic operation with a radiometric precision of
+2% and accuracy of +5%. The programmable calculator permits simple check-
ing and resetting of the wavelength calibration with a mercury arc lamp;
it also stores the system spectral response and automatically corrects for
spectroradiometric calibration. A spectral scan, with wavelength steps
of 1 nm, is achieved in 5 minutes. Thereafter the detailed spectral data
are printed out, along with an integral weighted by a preprogrammed action
spectrum. Stray light rejection of 10~^ is achieved with a single mono-
chromator, and 5 x 10~8 is achieved with a double monochromator. Sensor
heads for the single and double monochromator units measure 28 x 20 x 10 cm
and 28 x 25 x 10 cm, respectively. Versions of the instrument are now
manufactured by several companies.
d. Iignersible Spectroradigmeter
Scripps Institute of Oceanography (University of California)
is developing an immersible spectroradiometer for studies of UV-B attenua-
tion in aquatic environments (Smith, 1977). This has many features that
are similar to the Norris Spectroradiometer described above. It uses a
teflon-bubble entrance window, a double monochromator, a photomultiplier
tube, a microprocessor, and a programmable calculator for flexible, auto-
matic operation and ease of calibration. Initial underwater field tests
were made in October 1977.
e. Argon Mini-Arc
Short-term EAGER funds supported the continuing development
at NBS of the Argon mini-arc, a transfer standard of spectral irradiance
that is compact enough to be taken to the field for simple instrument cal-
bration. Its spectral irradiance at 300 nro approximates that of the sun at
the earth's surface and is stable to within +2%. Units can be rented from
NBS on a weekly basis by field and laboratory experimenters (NBS, 1977).
f• BZ Fluorescent Lamp
The BZ fluorescent lamp was developed at NBS with short-
term EAGER support. It provides output in the 275 to 350 nm spectral
30
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range with precision and accuracy of 2 to 3% and 5 to 6% respectively.
In the 280 to 300 nm range the spectral output closely duplicates the
solar spectral irradiance at the earth's surface. Calibrated units can
be purchased for $400 (NBS, 1977).
F. Integrated Assessment
1. Background
The development of rational policies to regulate CFCs and other
threats to the atmosphere requires that available information be assembled
in some logical manner in a system designed for use by decision makers.
Initial efforts in this area were presented at the BACER workshop in
September and continue at the University of Maryland. These efforts have
provided the framework for an optimum control (decision) model capable of
accommodating the complexities and uncertainties surrounding the question
of ozone depletion. In addition to providing a basis for regulatory*
decisions, an optimum control model also indicates how the decision could
be improved by reducing the uncertainty associated with the variables in
the model. With this information, research budgets may be allocated to
those topics that will be of most significance in making the policy or
regulatory decision. A major part of this model is the specification of
the linkages between the physical and biological impacts and the social
and economic consequences. There are many areas of uncertainty regarding
the response of the social and economic systems due to changes in UV-B
and climate, in addition to the basic uncertainty as to whether ozone
depletion would in fact lead to climatic change.
2. Current Research
a. Social and Economic Effects
Impacts from ozone depletion lead to a host of economic
and social concerns. Increased UV-B radiation directly affects humans
and other biological systems and subsequently leads to secondary social
or economic impacts (e.g., health care costs, and reduced crop yields).
Aside from increased UV-B incidence, ozone depletion could result in
31
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other changes in the incidence of solar radiation, including IR and
visible light, giving rise to potential changes in the climate. These
climatic changes also lead to secondary social or economic impacts.
Research to date has focused on reducing uncertainties of the primary
effects. Studies on social and economic issues have proceeded at a
slower pace, awaiting quantification of these primary effects on climate,
health, and other biological systems. To provide some insight on the
complexity of the issues and the general magnitude of the costs involved,
the relationships between climate change and associated economic impacts
are considered below.
The U.S. economy is highly sensitive to variations in
weather and climate. This sensitivity arises through weather effects in
three principal areas: (1) food production, (2) energy demand, and (3)
other aspects of human life that are subject to disruption by weather.
An'initial comprehensive body of research on the economic and social im-
pacts of climatic change was undertaken under the auspices of CIAP.
Since the physical and biological phenomena governing ozone depletion and
UV-B impacts were poorly understood, the economic analyses conducted
under CIAP were parametric in approach. Consequently, there exists con-
siderable uncertainty in the magnitude of the impacts estimated.
One of the CIAP studies addressed the economic effects of
a 1°C decrease in mean annual temperatures. While the estimates were
highly speculative, they served to identify the economic impacts and
estimate the general magnitudes of the costs involved. Annual impacts
were expressed in terms of 1974 dollars and ranged as high as $3 billion
due to decreased forestry production alone. Other areas (e.g., rice
production, marine resources, and health care exclusive of skin cancer)
had comparable adverse effects.
There are several other examples of climatic variability
affecting food supplies, energy demand, and other aspects of human life.
The next example demonstrates the need for a technique to quantify the
effect of ozone depletion on regional temperature and precipitation.
Consider first the record of world grain reserves shown in Figure 4.
32
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25
u>
20
O
t
5
D
§
_i
< 15
I-
UJ
O
QC
U
O.
10
1962
I
1964
1966
1968
YEAR
J L_
1970
1972
l_
1974
1976
FIGURE 4 WORLD RESERVES OF GRAIN AS PERCENT OF TOTAL ANNUAL CONSUMPTION (1961-1976)
-------
World grain reserves have been declining during the past 10 or 15 years
and are now approximately at the level of weather-induced fluctuations in
annual yield (Strommen, 1977). Figure 5 shows a record of weather-related
impacts on grain production in the two largest grain-producing regions of
the globe, and Figure 6 shows the record of global average surface temper-
ature. It can be seen that there was a rather steady decline in global
average surface temperature during at least the first 15 years of the
grain-yield record. Nevertheless, although there were many weather-related
yield decreases during this period, there is no evident relationship
between the frequency of weather impacts on grain production and the
global average temperature. Also, there is no simple relationship between
the set of years when U.S. yields were affected and the set when USSR
yields were affected.
This lack of simple relationships occurs for two reasons.
First of all, precipitation changes, rather than temperature changes,
were the major reason for weather-related crop impacts in many years (and
there is no known simple relationship between global average surface tem-
perature and regional precipitation). Second, climatic patterns that
reduce agricultural yields in one region can often result in more favor-
able climate change in another region, and hence in improved yields there.
Another example of the importance of regionality and precipitation is
provided by the severe winter of 1976-1977. In that winter the eastern
United States experienced record cold and heavy snowfall while California
suffered a record drought. The severe weather in the east not only
increased energy demand but also disrupted transportation and threw many
people out of work while fuel supplies were interrupted. The total cost
to the U.S. economy was far in excess of the cost of additional fuel con-
sumption, and in fact required revision of President Carter's targets
for U.S. economic performance. Additional costs were later incurred by
the agricultural effect of the California drought.
At this stage it is not possible to accumulate impacts
and arrive at a total cost for a hypothetical change in temperature or
precipitation, because all the impacts have not been identified and
quantified. However, from the figures presented, it is obvious that
34
-------
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33
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ill O>
0.50
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UJ 8
K g
uj £ 0.20
0.10
LU
cc
1880
1890
1900
1910
1920
YEAR
1930
1940
1950
1960
1970
FIGURE 6 VARIATION OF GLOBAL MEAN SURFACE AIR TEMPERATURE. Five-year averages from 1880-1884
to 1965-1969. Source: Strommen (1977).
-------
there is a chance for substantial losses in several areas of human
activity.
b. Research to Support Regulatory Decisions
By the time PL 95-95 was enacted, research programs had
become more focused toward providing a framework for regulatory decisions,
At about this time the economics department of the University of Wyoming
completed a cost-benefit analysis of nonessential uses of CFC for the
EPA; A. D. Little and International Research and Technology each com-
pleted studies on the economic impact of regulating CFC emissions; and
RAND currently is undertaking a more rigorous analysis of data needs
and economic impacts on industry of possible regulation of non-aerosol
CFC emissions.
On the topic of regulatory alternatives, the University
of Wyoming examined the costs and benefits of regulations directed
toward the various uses of fluorocarbons. This preliminary cost-benefit
study brings out the difficulties that one encounters when working with
large uncertainties regarding the physical effects of fluorocarbons.
The University of Wyoming group suggests research strategies to reduce
the uncertainties in the physical realm while attempting to minimize the
costs of adverse and irreversible effects of fluorocarbons. With regard
to the evaluation of regulatory alternatives, it appears that combining
the expected benefit criteria with safety-first concepts would have a
high payoff.
Toward the goal of providing decision makers with the
means of making an integrated assessment, the EAGER program is currently
funding development of an optimum control model for integrating the physi-
cal, biological, and economic findings. The purpose is to provide the
decision maker with a system for evaluating alternative control (and
non-control) strategies.
3. Future Needs
Past work has identified many gaps and uncertainties regarding
the understanding of ozone depletion and the consequences for existing
37
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economic and social systems. Nevertheless, it is necessary to integrate
the available information and to establish a framework for future regu-
latory decisions. Accordingly, Table 5 identifies three programs with
short-term payoffs that will lead to the efficient realization of these
goals.
The first need, an interdisciplinary workshop, helps establish
a common foundation of knowledge and needs for the scientific community
and decision makers alike. The second need, an optimum control model, is
the decision maker's primary tool in assessing the effect of various
regulatory strategies. This need also encompasses improvements in the
individual components of the model such as:
• Development of an integrated optimum control model to assess
the effect of regulatory strategies.
• Estimation of the value of additional information on direct-
indirect effects.
• Improvement of methods or models for quantifying the economic
and social effects of climatic change.
• Assessment of the alternative measures of morbidity and
mortality for use in evaluating costs.
• Assessment of the economic and ethical issues associated
with risks imposed on current population and on future
generations.
Participation at the 1977 EAGER workshop (EPA, 1977) raised
ancillary issues, such as the need to include the costs of regulating in
any policy analysis. Other suggestions were directed to topics that
would (1) ensure a holistic approach encompassing all identifiable benefits
and costs, (2) help to establish a baseline from which costs and benefits
could be measured, and (3) consider distributional aspects—both interna-
tional and within the United States. Little was said regarding social
impacts—in large part because behavioral responses are difficult to
predict.
38
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Table 5
INTEGRATED ASSESSMENT NEEDS
Description
Benefit
• Interdisciplinary Workshop. Continue to support an
interdisciplinary workshop along the lines of the
September 1977 EAGER workshop; this will enable the
latest research findings to be incorporated into
the decision process (model).
• Optimum Control Model. Continue development of the
optimum control (decision) model, which assesses
the effect of regulatory strategies. Refine the
social and economic components by supporting further
cost-benefit analyses.
• Prioritorize Future Research. Identify the most
serious data gaps in the integrated assessment
process. Rank these by estimating the value of
the additional information against the cost of
obtaining it.
Short term
Short term
Short term
39
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REFERENCES
1. Cutler, S. J. and J. L. Young, Jr. (eds) , 1975: "Third National
Cancer Survey: Incidence Data," NCI Monograph No. 41, DREW Publi-
cation No. (NIH) 75-787, Department of Health, Education and
Welfare.
2. Dickson, R. R. , 1977a: "Weather and Circulation of November 1976—
Record Cold over the South and Midwest for the Second Consecutive
Month," Mon. Wea. Rev_._, Vol. 105, pp. 239-244.
3. Dickson, R. R., 1977b: "Weather and Circulation of February 1977—
Widespread Drought," Mon. Wea. Rev., Vol. 105, pp. 684-689.
4. EPA, 1977: "Workshop, Biological and Climatic Effects Research,"
Transcript of Proceedings, September 19-21, University of Maryland,
College Park , MD.
5. Geisler, J. E., 1977: Proceedings of the Workshop on Regional Climate
and Stratospheric Change, sponsored by U.S. Environmental Protection
Agency, published by National Center for Atmospheric Research,
Boulder, CO.
6. Hudson, R. D., ed. 1977: "Chlorofluoromethanes and the Stratosphere,"
NASA Reference Publication 1010, National Aeronautics and Space Ad-
ministration. Available from National Technical Information Service,
Springfield, VA 22151. Note: Important revisions to this report are
contained in NASA, 1977 (see below).
7. Kessler, K. G.,1977: "UV-B Instrumentation Development," Quarterly
Report of June 15, 1977 on EPA/NBS Interagency Agreement EPA-IAG-
D6-017, National Bureau of Standards.
8. Lancaster, H. 0., 1956: "Some Geographic Aspects of the Mortality
From Melanoma in Europeans," Medical Journal of Australia, Vol. 1,
pp. 1182-1187.
9. Lancet Editorial, 1971: "Sunlight and Melanomas," Lancet, Vol. 1,
pp. 172-173.
10. Lee, J.A.H. and J. M. Merrill, 1970: "Sunlight and the Aetiology
of Malignant Melanoma: A synthesis," Medical Journal of Australia,
Vol. 2, pp. 846-851.
11. Machta, L. and W. Mass, 1977: "UV-B Measurements," paper presented
at BACER Program Planning and Review Workshop, University of Mary-
40
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12. NASA, 1977: "Effects of Chlorofluoromethanes on Stratospheric
Ozone: Assessment Report, August 1977," National Aeronautics
and Space Administration. Note: This report contains important
revisions to Hudson, 1977 (see above).
13. NBS, 1977: "State-of-the-Art Uncertainties and Limitations in UV
Spectroradiometry," in Optical Radiation News, No. 20, April 1977.
Published by National Bureau of Standards, B308 Meteorology Building,
Washington, D.C.
14. Norris, K. H. and J. D. Rowan, 1977: "Instrumentation for Measur-
ing Irradiance in the UV-B region," First Interim Report to EPA-
BACER, Supported by EPA/USDA Interagency Agreement EPA-IAG-D6-0168,
Instrumentation Research Laboratory, U.S. Department of Agriculture,
Beltsville, MD.
15. Smith, R., 1977: "Penetration of UV-B into Natural Waters," paper
presented at EAGER Program Planning and Review Workshop, University
of Maryland, College Park, MD, 19-21 September 1977.
16. Sprigg, W. A., 1977: "Climate Modeling and Diagnostic Research:
Reconstruction of Past Climatic Changes Associated with Global-
Scale Warmings and Coolings," Report of Research supported by
EPA/NOAA Interagency Agreement EPA-IAG-DG-0170, pp. 1-22, National
Oceanic and Atmospheric Administration, Rockville, MD.
17. Strommen, N. D., 1977: "The Effects of Climatic Change (Variability)
on Agriculture," paper presented at BACER Planning and Review Work-
shop, University of Maryland,College Park, MD, 19-21 September 1977.
18. Urbach, F., R. E. Davies, and D. Berger, 1974: "Estimation of Effect
of Ozone Reduction in the Stratosphere on the Incidence of Non-
melanoma Skin Cancer," in Proceedings of the Third Conference on
the Climatic Impact Assessment Program, February 26-March 1, DOT,
TSC-OST 74-15.
19. USDA, 1977: "Grams," p. 29, Foreign Agriculture Circular FG 3-77,
U.S. Department of Agriculture, Washington, D.C., March 23, 1977.
20. Wagner, A. S., 1977a: "Weather and Circulation of October 1976—
Record Cold over the South and Midwest," Mon'. Wea. Rev., Vol. 105,
pp. 121-127.
21. Wagner, A. J., 1977b: "Weather and Circulation of January 1977—
The Coldest Month on Record in the Ohio Valley," Mon. Wea. Rev.,
Vol. 105, pp. 553-560.
41
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22. Webb, T., 1977: "The Early Holocene Period of Climatic Warming:
Paleoclimatic Maps Derived from Pollen Data," Final Report to National
Oceanic and Atmospheric Administration, Brown University, Providence,
RI.
23. Wigley, T.M.L., 1977: "Geographical Patterns of Climatic Change:
1000 BC-1700 AD," Interim Final Report to National Oceanographic and
Atmospheric Administration, Contract No. 7-35207, University of East
Anglia, Norwich England.
42
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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
. REPORT NO.
600/8-78-002
2.
TITLE AND SUBTITLE
Results of Research Related to Stratospheric Ozone
Protection
5. REPORT DATE January
(requirprl hy law)
I. RECIPIENT'S ACCESSION NO.
6. PERFORMING ORGANIZATION CODE
AUTHOR(S)
R.E. Ruff, P.B. Russell, S.D. Kaplan, B.R. Holt, and
J.W. Ryan
8. PERFORMING ORGANIZATION REPORT NO.
6806
. PERFORMING ORGANIZATION NAME AND ADDRESS
SRI International
333 Ravenwood Avenue
Menlo Park, California 94025
10. PROGRAM ELEMENT NO.
1AA751
11. CONTRACT/GRANT NO.
68-01-3939
12. SPONSORING AGENCY NAME AND ADDRESS
Office of Health & Ecological Effects, OR&D - RD-683
U.S. Environmental Protection Agency
401 M St. S.W.
Washington, B.C. 20460
13. TYPE OF REPORT AND PERIOD COVERED
FY 76-77;
14. SPONSORING AGENCY CODE
EPA/600/18
15.SUPPLEMENTARY NOTES First Research Report to Congress, required by the Ozone Protection
Sections of the Clean Air Act Amendments of 1977; PL 95-95
16. ABSTRACT Research on ozone protection has been coordinated under the Biological and
Climatic Effects Research (EAGER) Program. This is a multiagency, multidisciplinary
effort initially funded by The Environmental Protection Agency. Its purpose is
to reduce uncertainties regarding ozone depletion to improve regulatory decision-
making. Health, biological, ecological, climatic and social/economic effects are
studied. Activities include surveys of skin cancer among populations at different
latitudes, measurements of solar UV-B (290-320 nm) at the sites, tests of over 100
plant species under simulated and natural UV-B levels, experiments with aquatic
ecosystems, and social/economic workshops. Results to date are as follows: surveys
generally support belief that skin cancer incidence is related to UV-B exposure;
mortality from skin cancer is increasing among the young, probably due to changes in
life style—more time outdoors; all plants tested are sensitive to UV-B at some
exposure level; some plants are stunted, others suffer bleached or discolored leaves;
UV-B damages larvae of shrimp, crab, mackerel and anchovy; photorepair mechanism
is suggested as a potential mitigator of UV-B effects in plants; field type, medium
resolution spectroradiometer and calibration standards were developed; and a
conceptual model, including parameter uncertainties, is developed for integrated
assessment of costs/benefits of control vs. non-control. Reliability of assessments
increase as parameter uncertainties decrease—do not have to revise model for new
data. _____^___ —
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.IDENTIFIERS/OPEN ENDED TERMS
cos AT I Field/Group
Ozonosphere
Ultraviolet Radiation
Skin Cancer
Photosynthesis
Photobiology
Climatic Changes
Econometrics
EAGER
(Biological and Climatic
Effects Research)
Benefit Cost Analysis
Risk
Confidence Limits
0401
0402
0606
1401
OJ01
1201
1202
18. DISTRIBUTION STATEMENT
19. SECURITY CLASS (ThisReport)
u
20. SECURITY CLASS (Thispage)
U
21. NO. OF PAGES
_52_
22. PRICE
EPA Form 2220-1 (9-73)
OU.S. GOVERNMENT PRINTING OFFICE.1978 260-880/78 1-3
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