The recommendations about impacts and adaptations are grouped into three classes. The classes were defined by the panel, and in its judgment the recommendations within the three classes are justified by the assumptions, analyses, and findings stated throughout its report. The first class concerns information and analysis, getting the facts straight and sharing them with people who must decide how hard to try to stop the climate from changing and how to adapt. The second class refers to improving rules and building institutional strength. This is the organizational framework for action. The final class is specific actions requiring investment of hard cash now or soon in ways to reduce future harm and aid adaptation.
Improve Information and Analysis
Assess Actual Climatic Impacts
Understanding the impacts of climate now and in the past is the bedrock on which analyses about the future must rest. Every year there are droughts, heat waves, severe storms, and all the other phenomena that are expected to change frequency or location in the future. Understanding how strongly our economy and environment are affected by climate now and how they are changing over time is necessary to help in making decisions about the scale and direction of investments.
Perform Research and Development
Adaptation for Climate Change
The spectrum of effort from basic research to development needs to be directed at climatic sensitivities, impacts, and adaptation. Both studies of
contemporary analogues of future climate changes and studies that are based on scenarios generated by numerical models can be useful. Studies are needed of such subjects as water and ecosystems, and they should be integrated to create a larger, coherent picture. Social, demographic, economic, and ecological data for both the United States and other countries need to be improved to aid impact assessments and adaptations.
Although estimates of impact and suggestions of adaptation abound, many suffer from four shortcomings. First, they may assess, say, the fall in yield of 1990 wheat caused by a 1°C warming in 2030, ignoring the proven adaptability of farmers, who will not behave in 2030 just as they do in 1990 if their environment has changed. Second, the studies may ignore technological changes, such as improved wheat strains. Third, the assessments are usually made without regard for the background of other changes that will affect impacts, for example, how markets for food products are changing and how production is shifting around the world from one region to another because of changes in comparative advantage. Fourth, suggestions of adaptations may fail to anticipate such side effects as salinity from irrigation.
Similar issues arise in impact studies of unmanaged ecosystems, which often study the response of a single species, neglecting the impact of other blows, such as chemical pollution, and amidst the competition and contributions of other species that grow with it. How will one species succeed another as the system adjusts at a place? How will a system of plants and animals migrate if climatic zones shift over half a century?
Many studies of adaptation must be conducted outdoors and in the current climate. The need for specialized research and development concerned with changing climate is moderated by the fact that the climates that may be experienced in 2030 are, for the most part, climates that are today being experienced somewhere, probably nearby. If the climate of Nebraska is going to become like that in Oklahoma today, experiments in Oklahoma fields now help later adaptation in Nebraska. Nevertheless, keeping in mind knowledge from simplified and controlled experiments and searching for global principles rather than catalogs of empiricisms, scientists must learn how disparate, entire systems of species live and reconstitute themselves outside as the environment, especially the concentration of CO2, changes. Analysis must include so-called pests whose depredations depend on the quality of the host and environment and alter the outcome outdoors. For crop varieties a sound strategy continues to be maintaining diverse strains and adapting them to the weather of the current decade, because the climate of the next decade will not be vastly different, even if climate is changing over a century, and because the useful economic life of a cultivar is only about a decade. It will be useful to demonstrate in the reality of outdoors how to shorten long renewal times so that man-made things can be, and natural things will be, promptly adapted to climate.
Monitor the Climate and Forecast the Weather
Monitoring the current climate and disseminating information about it can aid adaptation. It is useful for people to know if climate is already changing and how. For adaptation, monitoring of the air, streams, and seasonal events in individual localities is what matters. In Chapter 35 we have identified indicators of particular use. Monitoring global and regional climate is also necessary to test predictions of future climate, as discussed by the Effects Panel (Part Two).
Weather forecasts aid adaptation. Improved forecasts on all time scales, from hours to weeks and seasons, help. If warned a few days ahead where and when a hurricane or frost will strike, people can retreat from the shore or buy fuel to warm an orchard. If people know a few weeks ahead whether the season will be dry, they can choose the appropriate crop or store water. Accurate forecasts make all climates safer and more productive.
Since the modern science of meteorology began a century ago, forecasting has gradually improved, and there are reasons to be confident that further improvements can be achieved. In the greenhouse issue, the United States and other nations should find strong, sustained motivation to improve forecasting and the data and research that make the forecasting possible. The quality of weather analyses and forecasts in many poor countries, especially in the tropics, is markedly lower than in industrial countries, particularly in the northern hemisphere. Advances in numerical modeling and extension of technology for monitoring in tropical regions can cause improvements.
Consider Efforts to Advance Regional Mobility of People, Capital, and Goods
Expanding the territory over which impacts are absorbed and adaptations can occur has historically been a major way to lessen the adverse consequences of climate and weather. For example, food shortage is a greater risk in societies that rely only on local supplies than in those that draw their food from wide areas. Countries vary greatly in their expanse and the range of climates that they encompass, and the ones that are diverse in climate and economic activity are more able to adapt to climate changes.
In general, the questions about opening borders to goods, capital, and people are highly political, raising issues far beyond concerns about future climate change. Nonetheless, we can remind ourselves that larger agglomerations are more robust and able to adapt to climate change than are smaller units. More open and freer trade in goods and capital by themselves will
enhance the ability of countries to absorb climate shocks; in a regime of free trade, countries that lose comparative advantage in one climate-sensitive industry (e.g., timber produced in frosty climes) can move to other industries (e.g., fruits produced in warmer climes) and be ensured that markets will be available.
Although freer trade in goods has increased in the last half-century, nations have been increasingly reluctant to allow free migration of people. Countries with roughly the same living standards, however, may find it in their long-run economic interests to consider regional agreements for freer migration. The European Community constitutes an enormous climatic region and during this decade will move to a policy of free internal mobility of its laborers. In the years to come, the major challenge will be to deal with the flows of refugees, and if climate change becomes swift, nations may need to consider how to cope with large numbers of environmental refugees.
Build Effective Government
All adaptive strategies will benefit from administrative capability. In a country like the United States, the establishment and strengthening of agencies like the National Oceanic and Atmospheric Administration, the U.S. Army Corps of Engineers, the Department of Agriculture, the Forest Service, and the Federal Emergency Management Agency have been integral aspects of adaptation to climate. In a rapidly changing climate in the United States, their missions would become even more important. Making such agencies as effective and informed as possible will facilitate adaptation.
While some governments have developed the institutional means to adapt to harvest failures and floods, the governments of countries that are most vulnerable to climate change should take steps now to enhance the capacity of relevant organizations.
Effective government will be useful in the face of climate change not only at the national level but at the local and at the intergovernmental levels as well. Well-administered agencies at the international level in disaster and famine relief, as well as in meteorology and environmental protection, will facilitate adaptation. Thus, we recommend continuing and increasing U.S. support for the World Meteorological Organization, the World Climate Program, the United Nations Environment Program, and other relevant organizations.
In societies like the United States, most adaptation to changing climate takes place through decentralized individual reactions to social, economic,
and political signals. When a war reduces the availability of oil, requiring a reduction in oil consumption, society adjusts primarily as individuals reduce their consumption in the face of higher prices and lower incomes. When changing climate or shifting patterns of comparative advantage shift the relative productivity of different regions, individuals adaptchanging cultivars, occupations, or even residencesprimarily in response to signals of prices and incomes. However, where market signals are impeded (such as with price controls or in nonmarket economies), adaptation to changing environments is slowed.
In general, adaptation will be speeded if market signals, primarily prices, reflect changing conditions quickly. Where feasible, governments should work to improve markets, particularly where price signals are missing or misleading.
Outside the United States, particularly in nonmarket economies, the opportunity for market mechanisms to signal climate change is large. Many countries insulate their farm prices from world prices, slowing adjustment and increasing waste.
For the United States, particular concerns are water systems, risk, and environmental externalities. Here and in many other nations, water is allocated largely by water rights. By encouraging water auctions or market-based transfers, while remembering the public and environmental good, governments can prepare to adjust to new climates and water resources. Water markets can allow water to be used where it is most valuable. Also, if runoff changes, the market signals will evoke an efficient adaptation of its use.
Other concerns are risk and environmental externalities. Today, some insurance premiums do not reflect climate risks in areas subject to natural disasters. If premiums did, decisions about where to locate and what to build might be more logical. In addition, improved pricing of environmental externalities could help businesses decide better about adapting to climate change.
Adaptations can be made in anticipation of climate change, simultaneously with it or after it. In these recommendations, we emphasize anticipatory adaptation, since, for the most part, impacts lie some decades in the future. Deciding whether to adapt now or to wait will depend on such factors as the length of time until an adaptation is needed, the probability that it will be needed, the discount rate, and the cost of the adaptation now relative to later.
For example, anticipatory adaptation would be justified in a situation where the effects of climate change would be produced within 50 years, the
probability of climate change was at least 0.4, the uninflated discount rate was no more than 3 percent per year, and the cost of future adaptation (retrofit) was at least 10 times the cost of acting now. Possible worthwhile investments in anticipation of climate change are discussed below.
Preserve Biological Diversity
Biological diversity is a natural protection against surprises and shocks, climatic and otherwise. Among diverse species will be some adapted to prosper in a new landscape in new circumstances. In diverse species can be found genes to make crops prosper. So for security, preserving and encouraging biological diversity is recommended. This preservation should include varieties of commercial crops, wild relatives of these crops, and other species that so far lack values in current markets.
The unmanaged systems of plants and animals that are much of our landscape and oceans have a problematic future because of many man-made hazards. The anguish about these hazards arises in part from fears about risky consequences of the transformations and in part from doubting the righteousness of our dominion over living things and the goodness of our stewardship.
To date, most conservation efforts have assumed constant climates. If climate changes, existing reserves may become unsuitable for species currently living there, and landscape fragmentation may make migration more difficult. Therefore, conservation efforts need to give more attention to corridors for movement, to assisting species to surmount barriers, and to maintaining species when their natural environments are threatened. Expenditures for reserving land are an example of an investment that is likely to have a lower cost now than in the future and that keeps options open. At present, the potential for human intervention to ease adaptation in marine ecosystems seems limited.
Cope with Present Variability
Today droughts and floods, cold snaps and heat waves, all take tolls. Whereas justifying costly adaptations now for specified future climates is hard because the climate may never come while we pay interest for decades, the current fickleness of weather is sure and now. We thus recommend investments now to adapt to climate variability through such acts as improved insulation, better disaster management, and control of low coastal areas. Water supply is already sensitive to the variability of today's climate. Diversifying water supply over sources like streams and aquifers, over space and political boundaries by connections, and through time by storage and conservation increases reliability during changing climate.
Remember Long-Lived Facilities and Preservation of Heritage
When long-lived facilities are being planned or infrastructure is being renovated or replaced, investment in anticipatory adaptation is most likely to be justified. The method presented in Chapter 33, the section ''Making Decisions in an Uncertain World," illustrates the thinking needed for decisions about incorporating the possibility of climatic change into design. Such methods need to be elaborated.
It is not only functional facilities such as airports and water supply systems that may warrant modification or protection for the contingency of climate change. Every culture treasures buildings, neighborhoods, monuments, and other features of its heritage that may be affected by changing climate or rising seas. These structures in some cases have survived hundreds or thousands of years. Climate change joins a long list of threats to conservation of our physical and cultural heritage. Studies need to be undertaken in this area. It can be expected that investments will be justified to assure the longevity of our cultural heritage in the face of climate change.
People in industrial countries with diversified economies are best equipped to cope with the vagaries of climate change. By developing the necessary technology, they have found how to survive and flourish in almost all climates. By contrast, people in poor and small countries often have difficulty in adapting to even minor environmental hazards. Their primary need is for the development of strong and diverse economies when this can be done. But this cannot be achieved quickly. As we share a global interest in adaptation to climate change, we need to help others by finding means and setting conditions in which to transfer resources, knowledge, and technology and to ensure that the recipients can make good use of them.