This chapter is a revised version of a background paper prepared at the request of the Deputy Director of the U.S. National Science Foundation to be used for discussion at a meeting in Venice, Italy, in May 1988 of directors of science foundations or academies of the United States, Canada, France, Germany, Japan, Sweden, Italy and the United Kingdom.
Michael H. Glantz is head of the Environmental and Societal Impacts Group at the National Center for Atmospheric Research. He received his Ph.D. in political science from the University of Penna. His main areas of research relate to the interactions between climate and society with a special focus on drought.
After more than a decade of rather intense discussion and new scientific information on the warming of the global atmosphere as a result of increased emissions of greenhouse gases and of deforestation, one can still find hawks, doves and owls on this issue within the scientific community. "Hawks" believe that the evidence of a C02/trace-gases warming is very convincing and that the warming is already under way. "Hawks" represent the true believers. "Doves" (a dwindling number) feel that the greenhouse warming scenario is yet another doomsday scenario that will most likely fail to materialize. They often point to the failure of earlier doomsday scenarios for the environment to make their point. They tend to highlight the existing scientific uncertainties with regard to the global warming issue. Doves also include those who believe in societal ingenuity (the ability of society to respond or adapt to crises). There are activists among both the hawks and the doves. The "owls" have yet to make up their minds on the issue. They believe that, while the existing scientific evidence appears to be very convincing, there are some important pieces to the scientific puzzle that need to be put into place, such as the regional impacts of a global warming or the role of cloud feedback mechanisms.
The weight of evidence, despite some crucial, persistent scientific uncertainties, has shifted among scientists in favor of the position of the hawks. Carbon dioxide and other trace gases are observed to be increasing in the atmosphere and are apparently heating up the lower atmosphere to unprecedented levels (for recent decades) and at seemingly unprecedented rates. There is an increasing number of scientists in many countries (the Netherlands, the United States, Canada, Germany, Sweden, and the USSR, among others) who have become hawkish on the global warming issue and as a result have become more vocal about their views.
It appears that societies have embarked for some time on the course of unwittingly altering the chemistry of the atmosphere in such a way as to change our global climate. Revelle and Suess (1957) noted thirty years ago that humankind had embarked on a "large-scale geophysical experiment" by pursuing human activities that will ultimately alter climate in unknown ways. Today, however, we are on an advertent course. We have identified the problem and have speculated considerably about its societal, environmental, and political impacts. There is a growing awareness that, even if we stopped burning fossil fuels and manufacturing certain trace gases today, the problem would still be with us for decades into the future, as the greenhouse gases continue to remain in the atmosphere and as the oceans slowly respond to the warming. In other words, societies are already committed to at least some measure of human-induced global warming. Some groups have become deeply concerned about how future generations will be affected by the global warming.
All of this problem recognition notwithstanding, solutions have not been pursued, either by individuals, nations, or by international organizations, for a variety of reasons (discussed below). It could be that the debate on CO2 is only now heating up to the level where policies might be developed and actions taken to cope with the specter of an unprecedented global warming (e.g., International Conference on the Changing Atmosphere, held in Toronto, 27-28 June 1988). It is important, however, to put this recent resurgence of interest in the effects of increasing atmospheric carbon dioxide into perspective. Warnings by scientists regarding a global warming as a result of fossil fuel burning have been around since at least the end of the 1800s and early 1900s. The global warming "crisis" has apparently crept up on the international community over a period of a century (e.g., Ausubel, 1983; Kellogg, this volume). The question arises: when will decisionmakers ever have enough information to take deliberate action on this issue (inaction is also a form of action)?
Hawks, doves and owls can also be found in the policymaking community. For example, several U.S. Senators (e.g., Chafee, Gore, Wirth) as well as U.S. Representatives (e.g., Brown, Schneider, Sheuer, Skaggs) are seriously concerned about global warming and its potential impacts on the United States and the world, and so are now carrying the banner for action on this issue. Several hearings have been held-l by various subcommittees in the U.S. Congress on this topic (e.g., U.S. Senate, 1987).
In the international arena, the Executive Director of the United Nations Environment Programme, M. Tolba, has been concerned about the lack of international action on the global warming issue. Dutch policymakers, for example, worry about the sea-level rise aspect of the global warming as a large part of their country is below sea level. But there are also owls (perhaps the largest part of the international political community) and doves on the global warming issue. Because different communities are involved and within each community there are different perceptions of the seriousness of this issue, relative to other, perhaps more immediately pressing problems, it is no wonder that no general agreement about the issue has as yet formed either within nations or between them.
When considering a response to the greenhouse warming, societies everywhere and the people who govern them are faced with several problems. One problem can be represented by metaphors that we have been culturally taught to live by. These are norms that we take into account, at least subconsciously, before we make decisions. These norms, metaphors, or adages are frequently used by societies or by individuals as a general guide to their actions (Lakoff and Johnson, 1980). For example, "look before you leap" is sound advice that is often provided in response to the need to make a certain decision that requires careful consideration. But there is also the adage that "one who hesitates is lost," suggesting that a risk taker must make bold decisions. These two metaphors are in apparent conflict. Applying either of these adages in the absence of the other to the global warming issue would lead to totally different responses.
Another problem confronting decisionmakers relates to when to act on the CO2 issue. Three recent reports of possible policy responses to the global warming issue take very different positions. Mintzer (1987) has compared these studies. A 1983 study by Seidel and Keyes said it was too late to respond to a global warming because we have already committed ourselves to a warming. A National Research Council study in the same year suggested that nothing needed to be done in the near-term and that a "wait and see" approach seemed to be called for (Mintzer, 1987, 43). A more recent study by Mintzer suggests that it is not too late to restrict CO2 emissions and that "the longer the delay before preventive policies are identified, agreed upon, and implemented, the more extreme the policies imposed to stay within prudent bounds will have to be" (1987, 43). Clearly, there is no agreement on when it would be necessary to make public policies as a direct response to a global warming.
The timing of response to the global warming is not the only problem at hand. Another problem is having to decide when there is enough information to act. The scientific uncertainties surrounding the CO2/trace-gases issue are not insignificant; but there will always be some unresolved scientific issues on the causes and impacts of the global warming. How then should scientists as well as decisionmakers treat those uncertainties? In addition, it is not necessarily true that more scientific information will lead to more scientific consensus. The issue of a global warming is much clearer today than at any time in the past few decades, but those remaining scientific uncertainties must be put into proper perspective (are they major or minor?), lest they be used to paralyze any action, even educational, on the global warming issue.
Yet another problem with taking action relates to the fact that the C02/trace-gases warming is, as noted earlier, part of a process; from the mining of coal or the extraction of oil and natural gas, to their combustion, to their transport in the atmosphere, to their impacts on climate, to the impacts of the changes in climate on environment and society. The question frequently arises about where in the process societies should intervene in a purposeful way. This is an important question, because the answer to it will determine the kinds of policies that should be pursued, and the kinds of evidence needed to convince decisionmakers to pursue those policies. It will also determine the relative importance as well as direction of social science research needs. Related to the concern about where to intervene in the process is all the talk about strategies, that is, whether to focus attention primarily on prevention, mitigation, or adaptation to the yet-to-be-identified regional and local changes that would most probably accompany a global warming.
Some observers (Clark, 1985; Mintzer, 1987; Speth, 1987) have suggested that we move directly from scientific findings on the global warming issue to the making of policy. That may be an appropriate response at the emissions end of the process, if the reason for reducing the use of fossil fuels relates to resolving other problems as well (not just the global warming one), such as the push toward energy conservation or toward alternative sources of energy. If, however, the global warming issue is the only major driving force for an attempt to reduce fossil fuel combustion (or to reduce the other activities that abet the warming such as deforestation), then moving from scientific findings directly to policy formation will not necessarily work. What would be needed for most decisionmakers and for the general public would be reduced scientific uncertainty about the global warming issue in general, and, specifically, more "proof" about the regional impacts of the global warming as well as better information about society's ability to cope with climate variability and climate change.
The actors in the CO/trace-gases issue are many. They include producers, consumers and policymakers: the individuals who clear forested areas for agricultural purposes, automobile drivers, public service companies, coal miners, corporations that manufacture trace gases, government agencies that seek to develop their national economies, national decisionmakers, non-governmental organizations, international agencies, and so forth. These actors are directly or indirectly involved in the production of CO2 and other important radiatively active trace gases.
Yet another set of actors includes the physical, social, and policy scientists who have been meeting to discuss the global warming issue. They are actively trying to come to grips with this issue and their ranks are divided in terms of speculation about the regional implications of the warming and what might be done about those implications.
There have been several meetings of these actors in recent years to present their perspectives on the global warming issue, to question the science of the issue, to discuss potential impacts as well as possible policy options to cope with (prevent, mitigate, adapt to) the global warming; some of these meetings were held in Villach, Austria, in 1980, 1983, 1985 and again in September 1987. The most recent Villach meeting focused on developing policy options for responding to climatic change (WMO, 1988). In June 1988 the Canadian government convened a major international political conference entitled "The Changing Atmosphere: Implications for Global Security."
Interest in the policymaking aspects of the global warming issue is presently at an all-time high. The issue has achieved a new level of popular concern in the United States, partly because of Congressional hearings which have been held on this topic throughout 1987. More dramatically, the topic was graphically portrayed on the covers of the 19 October 1987 issue of Time magazine and the 11 July 1988 issue of Newsweek. Devastating drought occurred across North America in the summer of 1988. Dr. James Hansen, scientist at the Goddard Institute for Space Studies, believes that these droughts were the first conclusive manifestations of a global warming (Begley et al., 1988). International attention for this issue has been heightened by the news releases about the drawing up of the ozone protocol and by the mounting news releases about the greenhouse effect in market- and planned-economy countries, as well as in developed and developing countries.
WINNERS AND LOSERS
Regardless of what opposing view one might take with respect to the distant future, a global warming of several degrees Celsius will prove to be a boon to some and a bane to others, at least in the short term. Some areas will become drier while others will become wetter. Some areas will seemingly benefit from, and therefore desire, those changes while others will not. Clearly, there will be winners and losers. This perception about the potential benefits as well as adversities associated with the yet-to-be-identified regional impacts of a global warming will clearly serve to constrain international cooperation on the CO2 issue.
CO2 and Economic Development
If, for example, China proceeds with its economic development plans, coal will be its main source of energy. There may prove to be little that can be said to convince the Chinese to delay their plans for development in order to attempt to reduce CO2 emissions to the atmosphere. If China does cut back on its dependence on fossil fuels, in the absence of a viable replacement, it will surely be a "loser" with respect to development. If, however, it continues to use, or to increase its use of, fossil fuels it may or may not be a loser from the effects of the climate change.
To get the global community to consider alternatives will take creative thinking such as a suggestion that one of the industrialized countries, such as the United States, would cut back on its production of CO2 (this could be partially achieved by more efficient fossil fuel use) so that China could continue on its development course unfettered; or that one of the industrialized countries would compensate China for not increasing its use of fossil fuels.
A look at the USSR points out a similar dilemma. On the one hand Soviet scientists are among the international "whistleblowers" on the deleterious effects of a CO2/trace-gases-induced global warming. On the other hand, there are ministries within the USSR that are in the midst of carrying out major plans to develop Siberia and the fossil fuel resources in that region. There seems to be no tie-in within the USSR between these groups and no resolution of their opposing objectives and concerns. This is an example of the sensitivities of bureaucratic units within the same government, each with its own jurisdiction over a geographic or functional area and each responding to different sets of interests. A similar situation can be observed in the United States with respect to the development of oil reserves in Alaska.
The example of acid rain in the United States is somewhat analogous to CO2 and underscores the existence of bureaucratic (as well as political) jurisdictional disputes about whether a particular environmental problem is real and whether any consensus might be reached among those affected by the problem. Coal miners in West Virginia have a different view about the seriousness of acid rain-in the northeastern part of the United States than do those who live in the impacted region. Likewise, policymakers in the industrial Ohio Valley do not readily admit to their constituents' involvement in the acid rain problem nor are they willing to take steps that might prove financially harmful to the region's inhabitants.
Thus, even within countries and in regions within these countries there could be winners and losers if the use of fossil fuels and hence the emissions of CO2 continue even at present rates. How to restrain the activities of the potential winners and to compensate the potential losers are important issues that need to be addressed in both national and international policymaking circles. While more efficient energy use can result in some reduction of CO2 emissions, the alternatives such as shifting to a dependence on solar, wind, or nuclear energy may be costly--too costly for the developing countries. Are the industrialized countries willing (or able) to financially support such a shift within the developing world? Are the industrial countries willing to cut back their own fossil fuel use (by energy conservation and the use of alternative energy sources) in favor of the developing countries? After all, wasn't it the industrialized countries that loaded the atmosphere with CO2 and the other radiatively active trace gases in order to develop their economies? Shouldn't the developed countries reduce some of their fossil fuel dependence so that the developing countries can use fossil fuels to develop their economies? These difficult questions must be addressed.
TO ACT OR NOT TO ACT
The list of reasons for not doing anything about global warming is long: there are often other more pressing issues on any given day, the scientific uncertainties are important (e.g., the lack of knowledge at this time about regional specificity concerning the impacts of a climate change and about the role of cloud feedback mechanisms), conflicting interests within and among societies, the absence of an imminent "dread factor" (Slovic et al., 1980), problems associated with a common property resource, diffuse impacts on a global basis, perceptions of the problem as a long-term, low-grade one, the legacy of the supersonic transport (SST) issue of the early 1970s (British and French scientists versus American scientists), short time horizons of decisionmakers (versus time horizon of the impacts of a greenhouse warming), population increase, discounting the past as well as the future, viewing the warming as a process as opposed to an event, the problems associated with alternative energy sources, the potential for present "climate-related" losers to become "climate-change-related" winners and vice versa, the use of an inappropriate metaphor, and so forth.
The list of reasons that should push toward some degree of international action or at the least cooperation on the global warming issue is ostensibly much shorter: concern about the fate of the global environment, the view that with a climate change "nobody really wins," stress placed not on the short-term impacts but the longer-term benefits of action for the global community, a call for energy conservation (a good idea for some actors in its own right), the view that international agreements such as the Montreal "Resolution on a Protocol Concerning Chlorofluorocarbons" for the protection of the ozone layer (henceforth referred to as the ozone protocol) have been drawn up on extremely controversial issues that could serve as analogues to those interested in developing such a protocol for the global warming issue, individual and societal fear of or opposition to change, and so forth. Each of these reasons--- pro and con---will be discussed briefly.
CONSTRAINTS ON ACTION TO COMBAT
A GLOBAL WARMING
At any given point in time there will be issues competing for the resources (i.e., time, attention, and funds) of decisionmakers. Usually those issues that require most immediate action are considered first and those issues that are not necessarily associated with the normally defined criteria of a crisis (short time to act, high costs for not acting, etc.) are put aside. Each day there are new traditionally defined crises emerging and as a result those "less burning" issues become continually delayed, until at some time in the future they too are perceived to require immediate attention. In the mid-1970s, U.S. economist Robert Heilbroner expressed this view, noting that
The problem of global thermal pollution, for all its awesome finality ... stands as a warning rather than as an immediate challenge. Difficulties of a much more matter-of-fact kind--resource availability, energy shortages, the pollution resulting from noxious byproducts of industrial production--are likely to exert their throttling effect long before the fatal, impassable barrier of irreversible climate damage is reached (1975, 54-5).
There are many reasons why the global warming issue may not be perceived as a crisis in the traditional sense of the term. Although societal actions continue to aggravate the CO2/trace-gases-induced global warming today, there is a time lag (on the order of decades if not centuries) before we can clearly identify the impacts of our actions. In addition, there is enough scientific uncertainty surrounding this issue so that action can effectively be blocked, even by a minority opinion.
The CO2 aspect of today's global warming issue has been with us since the turn of the century (Arrhenius, 1896, 1908). It was debated then and faded away only to reappear as a scientific issue in the late 1930s (Callendar, 1938). It faded away once again, probably overridden by more pressing economic and political issues, and re-emerged as a scientific issue in the mid-1950s (Plass, 1956; Revelle and Suess, 1957), only to fade away once again. Its re-emergence in the 1970s, however, is unlike earlier ones. Now there is concern about the environmental and societal implications of a global warming and about the fact that the rate of change in the content of CO2 and other trace gases in the atmosphere is much larger now than it was at the turn of the century (WMO, 1979, 1983; NRC, 1983).
In the past, concern about such issues was minimal and it was felt (based on speculation) that the impacts would only be beneficial. For example, Callendar wrote that
In conclusion it may be said that the combustion of fossil fuel, whether it be peat from the surface or oil from 10,000 feet below, is likely to prove beneficial to mankind in several ways, besides the provision of heat and power. For instance the above mentioned small increases of mean temperature would be important at the northern margin of cultivation, and the growth of favorably situated plants is directly proportional to the carbon dioxide pressure.... In any case the return of the deadly glaciers should be delayed indefinitely (1936, 236).
Even the articles written in the 1950s were neutral with respect to the implications for society of a global warming.
As far as the scientific aspects of the global warming issue are concerned (with regard only to the burning of fossil fuels), it appears that most of the aspects discussed today (except for the role of the clouds, and perhaps the confounding effects associated with volcanic activity) were being discussed at least fifty years ago; the role of the oceans, the role of land clearing, the differential impacts according to latitude, even the projected temperature increases, and so forth. While we have acquired considerably more knowledge through modeling and paleoclimatic investigations, the scientific premise of CO2-induced global warming remains essentially the same as it was in the 1930s, as expressed by Callendar.
Conflicting Time Horizons
Social, economic, and political time horizons do not mesh well with the time scales on which certain environmental problems take place. While political leaders in the United States are elected either every two, four, or six years, environmental problems of the long-term, low-grade but cumulative kind evolve over much longer time scales. The mismatch between these time horizons often enables a given set of decisionmakers to delay responding to a call for action. The mismatch of time horizons also enables other "more pressing" issues, the outcomes of which can more immediately affect a policymaker's tenure in office, to up-stage the environmental problems considered to have dire consequences some time in the distant future. For any given issue, the general public and the media have a relatively short attention span.
Discounting the Future
While each generation tends to value its own consumption more highly than that of succeeding generations, some are willing to make great sacrifices to enhance the well-being of future generations and others are not. The conflicting values placed on decisions that might affect future generations can act as a constraint for action regarding the global warming issue. Contrary to popular belief, not everyone harbors good will toward societies that will exist decades or centuries in the future. Heilbroner addressed this issue, writing that
On what private, 'rational' considerations, after all, should we make sacrifices now to ease the lot of generations whom we will never live to see? There is only one possible answer to this question. It lies in our capacity to form a collective bond of identity with those future generations.... There are many who would sacrifice much for their children; fewer who would do so for their grandchildren. Indeed, it is the absence of just such a bond with the future that casts doubt on the ability of nation-states or socio-economic orders to take now the measures needed to mitigate the problems of the future [italics added] (1975, 115).
Discounting the Past
There is also a tendency to discount the importance or value of past experience, both in the science and the impacts related to the global warming issue. For example, some argue that the findings of Arrhenius in 1896 or Callendar in 1938 were not as certain as the results of current research, because today we have the best scientific and most current information available. Weighing only the results of present research makes the problem of global warming seem like a much more recent issue than it really is.
With respect to social impacts and discounting the past some observers assume that past experiences in dealing with climate change and climate variability can provide little insight into the societal impacts of a global warming. They say this because changes associated with a warming are suggested to be beyond anything encountered in human experience. Thus they are skeptical of mitigation or adaptation measures that may be proposed based on past experience. Not everyone agrees, however, that these past experiences should not serve as a basis for present and future action, as witnessed by the contributions to this volume.
Several important scientific uncertainties remain. As far as policymakers are concerned, it was only ten years ago that U.S. Congressional Hearings were held on climate change. At that time Congress, at the behest of the scientific community, was mainly concerned about the societal and environmental implications of a global cooling. Such publications as Ice, The Cooling, Fire or Ice, and Weather Conspiracy: The New Coming Ice Age appeared in bookstores. Studies of regional scenarios related to a global cooling were also undertaken at that time (e.g., Goldsmith, 1977; CIA, 1974). A turning point in the concern from global cooling to global warming occurred with the International Symposium on Long-Term Climate Fluctuations, held in the summer of 1975 (Kellogg, in this volume, Kellogg et al., 1975).
Global warming is expressed in terms of global mean temperatures. National, state, and local decisionmakers need to know, however, what that global mean will translate into at the regional and local levels. As of today, the general circulation models (GCMs) of the atmosphere have a poor record at producing scenarios (especially for precipitation patterns) for regions of the globe. Despite the fact that these models represent the best science and the best hardware available they do not yet produce (for the policymaking community) credible or reliable regional scenarios. Other approaches to the development of reliable and credible regional scenarios are presently being developed to complement those being produced by the GCMs (e.g., Parry et al., 1987).
Problems with Alternative Energy Sources
We can find supporters of solar energy joining hands with supporters of nuclear energy to identify the continued burning of fossil fuels as a major contributor to atmospheric pollution by trace gases. Their cooperation ends there. Clearly, the replacement of fossil fuels with nuclear power could substantially reduce CO2 emissions to the atmosphere. In practice, however, reliance on nuclear energy remains highly controversial and its development highly political. The technical problem of long-term storage of waste products has not as yet been solved. The cost of nuclear-generated electricity has been much higher than originally projected and plants have not worked nearly as well as expected. Thus it is much more expensive than energy generated from fossil fuels. Every time there has been a nuclear accident--such as at Three Mile Island (USA) or Chernobyl (USSR)--the plans for reliance on this form of energy become less popular as well as less certain. The technology of nuclear power generation is also very sophisticated and capital intensive, and would not be useful for transfer to developing countries. Solar energy, while used for hot water heating and electricity generation in some remote areas, is still in the experimental stage for large-scale electricity generation and not available as yet on a commercial basis. It appears that it will not be able to compete economically with fossil fuels, at least in the near future. Thus, more efficient use of fossil fuel energy seems the only present option other than the status quo. Lack of alternative energy sources that are both politically and technically acceptable is a constraint to the reduction of CO2 emissions.
Society is divided in many ways, along political, cultural, economic, and social lines. A change in the status quo (e.g., the dependence of some regions on the mining of coal or the extraction of oil or natural gas and of other regions on the burning of it) will be opposed by some groups in society while favored by others. Even the seemingly harmless suggestion that with energy conservation everyone wins is rent with conflict. For example, corporations that "sell" energy and workers whose livelihoods depend on the production of energy would most assuredly disagree. Even shifts within a country among fossil fuels, while reducing CO2 emissions (coal produces the most CO2 and natural gas the least, per unit of energy produced), would lead to political conflict between affected groups. In a democratic society it is not easy for long existing societal cleavages to be healed, allowing consensus for action on the global warming to be formed.
Obviously there are conflicting interests between nations as well. For example, while it is in the interest of the Chinese to develop their coal reserves to finance their economic development plans, or while it is in the interest of the oil producing countries to encourage the use of their oil, it will not be in the interest of low-lying coastal countries to suffer from the projected sea-level rise associated with a global warming. How, then, might a consensus for action be formed when these international actors have such diametrically opposed views and, in a global sense, conflicting priorities?
Populations are increasing around the globe, with rates in some developing countries approaching 4 percent per year. Growing populations require additional resources of food, water, land and energy. Furthermore, it is anticipated that as poor countries improve their economies, much more of their energy will be supplied from fossil fuels. Adding their rapidly growing populations to the expected increase in affluence (with improved economies) means that their share of global CO2 production will increase.
Populations in the industrialized countries increase slowly or not at all; but because per capita consumption of energy and other resources is extremely high, these countries contribute the major share of global CO2 emissions today. Stabilizing or reducing global CO2 emissions, then, raises a number of questions. What are the issues that surround the lowering of per capita energy consumption in the industrialized countries while permitting it to increase in the developing world? What is the best strategy for lowering energy consumption in developed countries? Is it possible to raise incomes in developing countries without following the same paths of pollution that the now-industrialized countries had followed?
The population debate is a highly charged political issue about which much has already been written. With regard to the global warming issue, it acts, in the short term, as a constraint on taking universal action to reduce CO2 emissions for two reasons. First, the scale of fertility declines and consequent population stabilization required to reduce total global demand for C02/trace-gases-producing commodities is likely to take many decades to accomplish even under the most favorable conditions. Second, it is necessary to reduce total demand for CO2/trace-gases-producing commodities in both industrialized and developing countries--first by improving efficiency and second by designing an energy economy that does not rely on fossil fuels.
Warming-as-Process Versus Warming-as-Event
Some people tend to look at the global warming primarily as a process; a long-term, low-grade, cumulative process in which today's amounts of CO2 and other trace gases in the atmosphere are much like yesterday's and will be similar to tomorrow's, but that in a year or so, the gradual change will be measurable; and in several years that change will become even more noticeable. They believe that the time to act is early in the process because of the nature of the greenhouse gases; they can remain in the atmosphere for many decades or longer.
Others, however, focus their attention on the warming primarily as an event. A doubling of CO2, for example, will at some time in the future mean higher temperatures, higher or lower rainfall amounts depending on the region of the globe, higher evaporation rates, higher sea level, and so forth. Those who perceive the warming as an event are looking for signs of change before they will join others in a call for action. Those signs of change may be subtle ones such as a separation of the climate change signal from the variability of normal climate conditions; or they may be major ones such as rapid rise in sea level, a disintegration of the West Antarctic ice sheet, or agricultural activities in such relatively inhospitable regions as Siberia or northern Canada. These conflicting perceptions of the global warming issue inhibit action on dealing with the issue.
The regional and local impacts of a global warming have not yet been identified, but even when the findings of the scientific assessments are presented (more rain, less rain, higher temperatures, higher sea levels, etc.), many countries will probably not believe that such seemingly small increases in temperature or unknown but seemingly not-so-severe changes in rainfall could be "all that harmful" and may in fact believe that they could prove to be generally beneficial. Sea level rise is one impact that seems to possess some credibility among coastal countries and low lying areas but the rates of increase and the ultimate level of increase remain controversial. At this time the scenarios that have been suggested for the future with a warmer earth's atmosphere are numerous, often conflicting, and quite possibly unreliable as forecasts of a future world. The use of global projections, therefore, with little reliable information on regional impacts, minimizes the "dread factor" that some scientists have attempted to associate with the global warming issue.
Lack of Dread Factor
There have been several attempts to identify a "dread factor" for the CO2/trace-gases issue, but none of these attempts has met with success. For example, in the late 1970s there was considerable attention by a few scientists (and the media) given to the prospect of the disintegration of the West Antarctic ice sheet and the drastic (5-8-meter) rise in sea level that would accompany the disintegration. Although debate on the role of the West Antarctic ice sheet in the sea-level issue remains, such a rapid rise in sea level has been discounted. Another attempt at finding a "dread factor" emerged during Congressional hearings when it was suggested that a CO2 doubling in the atmosphere (over pre-Industrial Revolution levels) would most likely occur in the first few decades of the 21st century. But soon less attention and importance was placed on a CO2 doubling, because it was assumed that no rapid changes could be associated with such a doubling. A recent attempt at identifying an "ozone hole" equivalent (i.e., "dread factor") appeared in an article in Nature (Broecker, 1987), in which the author suggested that "there is now clear evidence that changes in the Earth's climate may be sudden rather than gradual." In other words, policymakers should be prepared to cope with the impacts of step-like changes in regional climates around the globe. Yet, this too is speculation about how the course of global warming might proceed. The most recent attempt to identify a CO2/trace-gases-related dread factor was made by a prominent scientist, who has suggested that four of the hottest years on record have occurred in the 1980s (Begley et al., 1988). This claim has yet to be validated by the scientific community.
Many people have a blind faith in technology, holding the belief that human ingenuity in times of crisis will rise to the occasion and develop a way to make the global warming problem "go away." Such an attitude encourages procrastination on taking immediate or near-term action on a long term, low grade but cumulative environmental change.
The Supersonic Transport (SST) Legacy
In the early 1970s the U.S. scientific community was concerned that the exhaust from a large fleet of high-flying SSTs would ultimately deplete stratospheric ozone, thereby allowing more ultraviolet radiation to reach the earth's surface, leading to an increase in the incidence of skin cancer. This scientific issue became controversial within the United States as the SST issue became politicized, with political leaders (including the U.S. Department of Transportation and President Nixon) and some scientists on one side of the issue and environmentalists and other scientists on the other side (see Glantz et al., 1982, for a discussion of this issue).
This scientific issue was one of international concern as well, as scientists in the United States, Great Britain, France, and the USSR took opposing scientific points of view. These governments (except for the United States) had already decided to support the development of a high-flying fleet of SSTs (the Franco-British Concorde and the Soviet Tupolev), and their scientists, using essentially the same pool of technical information as used by the Americans, came up with an opposing position on the impacts of such an SST fleet. An article written by an American scientist appeared in Science in 1971 (Johnston, 1971) supporting the view of ozone destruction by a large, high-flying SST fleet. In 1973 an article appeared in Nature (Goldsmith et al., 1973) representing the British scientific view, noting that the impacts on stratospheric ozone of a fleet of Concordes would be relatively minimal. An assessment of this controversy in international science was written some years later and was appropriately entitled The Bias of Science (Martin, 1979). There is a legacy in this experience for the CO2 issue. Those countries that wish to "do something" about CO2 emissions, as well as those countries that do not wish to take action (for whatever reason), could search for, and most likely find, reasons to support their actions in the existing scientific literature.
The "Nothing to Lose" Syndrome
In many regions of the world the inhabitants might welcome a change in their climate. One scientist has even suggested that the increase of carbon dioxide in the atmosphere would help to close the gap between rich and poor nations. Indian scientist, J. Bandyopadhyaya (1983), in his book Climate and World Order has noted that, in contrast with the tropical regions, the temperate climate has supplied the industrialized countries with many permanent natural advantages and that climate has been and continues to be one of the major factors behind their accelerated development. While the industrialized countries are trying to "preserve the global climate status quo by fighting against 'climate variability"' by trying to inhibit the upper level of the global warming, it should be in the interest of the developing nations to change their tropical climate and to modify "the global climate dichotomy." Bandyopadhyaya based his argument on the view that a more uniform global climate would help accelerate the economic growth of the developing countries without adversely affecting the industrialized world. The preceding thoughts represent a perception that today's "climate-related" losers could become tomorrow's "climate-change-related" winners.
Societies are faced with many environment-related problems; ozone depletion, acid rain, air pollution, nuclear winter, and so forth. The images that the names of these environmental problems conjure up are negative ones. When it comes to the greenhouse warming metaphor, however, the image is a positive one. People have been taught for generations that greenhouses are good. They protect vulnerable plant life from harsh climatic conditions. They provide an environment in which plants can thrive through inhospitable seasons under the most favorable conditions. But today the metaphor of a greenhouse has been applied to the global warming situation. Now we are supposed to relate a "greenhouse gas" or a greenhouse effect to an adverse, harmful situation. Perhaps the use of the greenhouse metaphor has become part of the problem in getting people to take the global warming issue seriously. What may be needed is a metaphor that portrays an adverse condition, a phrase such as the "trace-gases pollution" problem. If the issue is referred to in this way, it might be taken more seriously by the general public and by the media as a threatening environmental change.
FACTORS FOSTERING COOPERATION TO COMBAT A GLOBAL WARMING
Concern about the Fate of the Global Environment
Environmental movements blossomed around the globe in the 1960s. Concern focused on the fate of the global environment including the overuse and misuse of natural resources. Many of the trends adversely affecting environmental quality identified in this era have continued into the 1980s more or less unabated: deforestation, desertification, soil erosion, population growth, atmospheric and oceanic pollution, among others. Carbon dioxide and stratospheric ozone depletion are just the latest issues to be taken up by environmental interest groups. There is a precedent of international cooperation on addressing such global environmental issues.
An environmental problem can be viewed as global in several respects: global in cause, global in effect, global in interest. This global interest can be witnessed by the series of international conferences convened by the United Nations in the 1970s to address problems of common concern: Conference on the Environment (Stockholm, 1972), World Food Conference (Rome, 1974), World Population Conference (Bucharest, 1974), Habitat (Vancouver, 1976) Water (Buenos Aires, 1977), Desertification (Nairobi, 1977), Science and Technology (Vienna, 1979). The concepts of "One Earth" and "Spaceship Earth" have certainly caught on as symbols of the human predicament among many segments of society.
Nobody Wins With Climate Change
The argument that nobody really wins with a global warming is based on the view that the sum of impacts of a climate change will be detrimental to humanity. If, for example, more rain appears in arid and semiarid regions, will the corresponding increase in food production compensate for a possible loss in formerly productive regions such as the U.S. Great Plains (a region from which food aid comes in times of recurrent, intense drought in arid and semiarid regions around the globe)? The same kind of argument can be made within countries as well. Agricultural productivity may benefit from a warming but what will happen to coastal areas as a result of the attendant sea-level rise? Many important coastal cities of the world would be at risk to sea-level rise of several meters (e.g., Barth and Titus, 1984; NRC, 1985; Bardach, 1987; Davidson, in this volume). In addition, perceived short term benefits must be weighed against the longer-term costs and benefits.
As a result of the increased cost of fossil fuels during the 1970s, energy is being used considerably more efficiently today, with the developed nations using less energy than was predicted in the early 1970s. There remains a large potential for using energy even more efficiently. The investments necessary to achieve this are cost effective at present energy prices (Krenz, 1980). Therefore, the developed nations can further reduce their fossil fuel use and thereby reduce CO2 emissions. This could allow developing nations to use more fossil fuels without increasing the present level of global CO2 emissions. The relatively simple technologies required for more efficient energy use can, of course, also be shared with the developing nations, thus further reducing the fossil fuel requirements for their development. The primary motivation for efficient use of fossil fuels would not need to be the reduction of CO2 emissions, since it would also benefit the balance of trade of energy-importing nations as well as conserve a finite, relatively scarce, resource.
Precedents for International Agreements
A paper trail of international agreements exists on issues that at one time were viewed as extremely controversial and seemingly intractable. Perhaps the most recent political one is the agreement reached in December 1987 and signed in June 1988 between President Reagan and Secretary General Gorbachev on the reduction of intermediate nuclear forces. With respect to the environment, the most recent agreement is the "Resolution on a Protocol Concerning Chlorofluorocarbons" signed in Montreal in September 1987. Therefore, one should not be deterred in one's efforts to reach some kind of international understanding on the global warming issue. In fact, at the International Conference on the Changing Atmosphere (held in Toronto, 27-28 June 1988), Canadian Prime Minister Mulroney initiated a process to develop an international law of the atmosphere in response to the CO2/trace-gases-induced global warming.
The Ordeal of Change
People often fear change. This could be a powerful factor in bringing nations together to discuss, if not actively combat, global warming. True, with a global warming there will be winners and losers, at least in the short term, but who will they be? True, different regions will be affected in varying ways by a warming, but will they be affected in positive or negative ways with respect to the way these societies operate today? In many instances, if given the choice, people would favor "the devil they know" over "the devil they don't know." A supporting argument could be made that it might be much easier to reach agreement on action to combat a CO2/trace-gases-induced global warming before the winners and losers have been clearly identified. Once winners and losers have been identified as such, the losers will seek change but the winners will oppose it. (See Brown, this volume, for an example of this situation with regard to the Colorado River Compact).
SOME INSTITUTIONAL ASPECTS OF THE GLOBAL WARMING ISSUE
Among those who consider the global warming issue an ominous environmental change that needs to be dealt with on more than an ad hoc basis, there is debate over whether existing institutions are appropriate for dealing with the issue. What institutional mechanisms are needed for dealing with the global warming issue, an issue that most observers consider a long-term, low-grade cumulative environmental problem? Some observers suggest that new institutional arrangements are required, such as the recently developed ozone protocol.
It is useful to examine this analogy further. In 1987, representatives of 24 nations and the European Community negotiated an international protocol on the control of the manufacture and use of CFCs. The proposed treaty, which must be ratified by at least 11 countries before it takes effect, calls for cutting world consumption of CFCs by 50 percent (of the 1986 level) by 1999 (C&EN, 1987, 1557). This has been suggested as a prototype of a process that might be pursued for controlling CO2 emissions to the atmosphere.
CFCs are used as spray can propellants, refrigerants, cleaning solvents, foam-blowing agents, and for other industrial purposes. The CFCs are inert chemical compounds that eventually diffuse to all parts of the atmosphere. In the stratosphere the chemical molecules are broken down by ultraviolet rays, freeing the chlorine atom to enter into catalytic reactions with ozone molecules. Chlorine in the stratosphere is an effective "ozone eater." With the destruction of stratospheric ozone more ultraviolet reaches the earth's surface, thereby increasing the incidence of skin cancer (and other health problems as well) among humans in addition to bringing about other deleterious effects, many of which are yet unknown, to living organisms. Moreover, it now appears that, incrementally, CFCs along with other trace gases (excluding for the moment CO2) are contributing to the global warming. Some observers suggest that these gases taken collectively might equal and perhaps surpass the contribution of CO2 to the global warming in the next few decades (e.g., NRC, 1983; Ramanathan et al., 1985).
The value of the actions suggested in the protocol to reduce CFC emissions notwithstanding, there may be little similarity between attempts to control CFC emissions and attempts to control CO2 emissions to the atmosphere. In other words, the recent ozone protocol may be a "misplaced analogy" to the CO2 issue. Despite apparent similarities in their impacts on the global atmosphere (i.e., their respective contributions to the global warming), there are important differences between these issues. For example, there is a "dread factor" that the public can relate to that is associated with the CFCs; increased CFCs decrease stratospheric ozone and therefore increase the incidence of skin cancer. With a reduction in stratospheric ozone there may be no winners. The risk of skin cancer will increase for everyone although certain populations are more at risk than others. Opponents of any restrictive action on CFC production point out that every day people are increasing their risk to skin cancer by moving from northern locations to southern ones (e.g., from Minnesota to Texas) or from low altitudes to higher ones; this is tantamount to an increase in exposure to harmful ultraviolet radiation. However, moving from one location to another involves individual choice; the consequences of ozone depletion allow no such choice.
For the CFCs there is an additional "dread factor"--the ozone hole. This factor, perhaps more than the others, has catalyzed policymakers (if not the protocol negotiators) to take action. To some the ozone hole over the Antarctic is a "warning shot across the bow"; if no appropriate action is taken now, a similar hole could develop in other parts of the atmosphere, over inhabited regions. Any near- or mid-term "dread factors" associated with the CO2 issue are less clear. Furthermore, there is no CO2 equivalent now to an "ozone hole" catalyst for action. The most recent catalyst for action on the global warming issue may prove to be a situation such as the increase in the frequency of extreme climatic conditions, as exemplified by James Hansen's belief that the four warmest years during the period of instrumental records (for global air surface temperatures) may have all occurred in the 1980s (Begley et al., 1988).
What will a warming do to climate and Human activities at the local and regional level--a little wetter, a little drier, a little warmer, a little colder, higher agricultural yields, lower agricultural yields? The "dread factor" associated with inaction on the issue of reducing the use of fossil fuels remains unclear. In other words the costs (or benefits) of inaction are not clearly identifiable. It is important to note that nonintervention (inaction) is also a form of intervention (action). Inaction may imply that the "dread factor" is not perceived to be high and therefore there is inadequate backing for action; or that a conclusion has been reached that there is time to act in the future, or that the costs of inaction at this time will not be high, or that the costs involved in viable action would be too high (e.g., shifting dependence from fossil fuel to solar or nuclear). Also, while individuals are quite aware (in a qualitative sense) of how they benefit from the use of fossil fuels, they are less aware of the need for CFCs. (Many people relate CFCs to propellants in hairsprays and underarm deodorants or containers for fast-food store hamburgers; alternatives have been found or are at least available in these instances in the United States.)
CFCs are the source of two environmental problems; a global warming and a depletion of stratospheric ozone. In light of this, another interesting question must be raised, one that might shed light on the use of the recent protocol to control CFCs as a model for future attempts to achieve a CO2 protocol: Would the 24 national representatives have agreed to the protocol negotiated in Montreal (or even met to discuss it) if the CFCs had been associated only with a global warming problem? Most probably not. I would venture to say that the skin cancer relationship to the depletion of ozone (a factor known and discussed since the mid-1970s) and the rapid sharp decrease in ozone over the Antarctic region served as the underlying cause and the catalyst, respectively, for public support for action to combat ozone depletion.
Both CO2 and CFC emissions are part of broader processes. One can find analogies and disanalogies between these two issues depending on the stage in the processes that one wishes to compare. For example, they could be analogous with respect to the impacts of both of these trace gases on climate. They are not analogous, however, in comparing their sources; only a small number of companies produce CFCs whereas innumerable individuals as well as factories are burning fossil fuels in one form or another, producing CO2 emissions.
Before accepting the analogy with the ozone protocol as a guide for trying to achieve an international agreement on CO2 emissions, one must make sure that a more appropriate analogy does not exist. If we can identify such an analogy, we might be able to gain some insight on whether and how to proceed at the national and international levels to secure an international accord of some sort on limiting future levels of atmospheric carbon dioxide and other radiatively active trace gases. What similarities, for example, might the CO2 issue (and process) share with such international processes as the development of the atmospheric test ban treaty, the nuclear non-proliferation treaty, or attempts to develop a New International Economic Order?
Several organizations are involved in the policy aspects of global warming, some more directly than others: in the United States these include but are not limited to the Environmental Protection Agency, the Department of Energy, the National Climate Program Office, the National Science Foundation, the World Resources Institute, Woods Hole Oceanographic Institute, the American Association for the Advancement of Science, the National Center for Atmospheric Research, the Geophysical Fluid Dynamics Laboratory, Goddard Space Flight Center, Goddard Institute for Space Studies, NASA, the National Academy of Sciences, and so forth. Internationally, the organizations that are active in the C02/trace-gases warming issue include the United Nations Environment Prograrmme, the World Meteorological Organization, the International Institute for Applied Systems Analysis, the Beijer Institute, the European Community, the International Council of Scientific Unions, and so forth. Clearly, there are numerous groups, centers, and institutes involved in this issue, in addition to scores of researchers at various universities around the world.
The International Council of Scientific Unions (ICSU), as well as the U.S. National Academy of Sciences and the U.S. Department of Energy, have raised concern about the scientific aspects of the problem. The Beijer Institute, the International Institute for Applied Systems Analysis, the World Resources Institute, the Hubert Humphrey Public Policy Institute, the U.S. Congress, the Environmental Protection Agency, and the U.S. National Academy of Sciences, have voiced concern about the need for some sort of policy action on this issue. What is it that is missing? What is not being done with the current arrangements that should be done? These are questions that need to be answered before we get involved in creating new national or international institutions to cope with the global warming issue.
Before we continue to search for new policy options and institutional arrangements in order to "deal" with the global warming issue, it would be wise to ask what it is that we would like such an international institution to do. Is it to be used as a forum where different views on the issue can be expressed and evaluated? Is it to be an advocacy institution (i.e., an interest group), carrying the message about the adverse impacts of a global warming to policy- and decisionmakers around the globe? Should such an institution be used to educate societies and policymakers about the potential consequences of a global warming? What is it that the new institution might do that could not effectively be done through existing institutional arrangements? We must avoid a "rush to judgment" on creating new international institutional arrangements to deal with the C02/trace-gases-warming issue until we have investigated the potential contributions and roles of existing institutions.
Why do we have a scientific community warning us of an impending climate crisis on the one hand and a lack of concerted response within countries and among them on the other? It appears (from the list of pro and con reasons for taking action on the global warming issue) that the reasons that constrain action are seemingly more specific and numerous than those reasons that promote action. Even the call to various policymakers to unite to combat an excessive global warming seems to have been falling (generally speaking) on deaf ears.
The past few decades have been filled with doomsday scenarios; limits to growth, stratospheric ozone depletion as a result of supersonic transport, the China syndrome, the food, water and energy crises, nuclear winter scenarios, and the like. Many of those doomsday projections have not yet materialized. Most likely they were made to draw attention to impending crises rather than to suggest that we were already committed to such scenarios. The global warming issue is the latest of this type of projection.
Even if this one is the real doomsday scenario, will anyone believe it? How does one build a sustainable, broad-based coalition to create a better earth or a more wholesome environment? How might we (humankind) circumvent these constraints and create an atmosphere whereby this problem can merit more sustained (as opposed to sporadic) and serious (as opposed to nominal) attention by policymakers, the public), and the media? How can we convince individuals, organizations, governments to take actions that would at least slow down, if not prevent, unprecedented levels of global warming from occurring--actions that would benefit humankind even if the global warming were not to occur for some as yet unforeseen reason? Other concerns that need to be addressed are as follows:
* What will be considered enough information to prompt action?
* When will we have that information?
* What are the identifiable catalysts to social action that might be analogous to the "ozone hole"?
* Where in the process of the global warming should societies act?
* What kinds of tradeoffs are societies willing to make to cut down global CO2 emissions?
* What is the appropriate process to pursue to reach an international agreement on the global warming issue?
* How can the sustained interest in this issue be maintained among the public, the policymakers, and the media?
* How important should the remaining "known" scientific uncertainties be as obstacles to actions on the global warming issue.
* What kind of credible and reliable social science research is needed to better understand this issue and societal responses to it?
* How can we develop reliable and credible regional scenarios that might occur under conditions of a warmer atmosphere?
These are but a few of the questions that need to be addressed if humankind is to understand and respond to scientific information on the global warming issue. These questions must be addressed in many different forums and by many different groups. The call to action by any one group will most likely require corroboration by similar pronouncements from different groups representing different interests.
I would like to thank the following people for their critical assessments of early drafts of this discussion paper: John Moore (National Science Foundation), John Steele (Woods Hole Oceanographic Institution) John Firor (National Center for Atmospheric Research (NCAR)), Robert Chervin (NCAR), Judith Jacobsen (NCAR), Dale Jamieson (University of Colorado), D.J. Fisk (Department of Environment, UK), Mario Pedini (Italy), Ralph Cicerone (NCAR), Pierre Lafitte (France), Nobuo Egami (National Institute for Environmental Studies, Japan), Paul Crutzen (Max Planck Institute, Germany), and Maria Krenz (NCAR). I would also like to thank Jan Stewart and Regina Gregory for their continued support during the preparation of several drafts of this manuscript .
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