Adapting to the Impacts of Climate Change (2010)

Below is the uncorrected machine-read text of this chapter, intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text of each book. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

CHAPTER ONE Introduction A daptation to climate change requires attention now because impacts are already being felt across the United States and further impacts are unavoid- able, regardless of how immediately and stringently greenhouse gas (GHG) emissions are limited (IPCC, 2007a; USGCRP, 2009). Adaptation to climate variability is nothing new to humanity, but it now seems very likely that climate conditions by the later part of the 21st century will move outside the range of past human experiences (IPCC, 2007b; Solomon et al., 2009). Therefore, historical records and past experience are becoming incomplete guides for the future, and adaptation to climate change needs to become a high national priority. Either we adapt by mobilizing to reduce sen- sitivities to climate change and to increase coping capacities now, or we will adapt by accepting and living with impacts that are likely in many cases to disrupt our lives and livelihoods. The questions are how, where, and when to adapt—and whether in some cases, if climate change is relatively severe, we may face limits on our ability to avoid painful impacts by adapting. ADAPTATION: KEy QuESTIONS, CHALLENgES, AND OPPORTuNITIES Why Consider Adaptation Now? Society and nature have always adjusted to climate variability and weather extremes, but climate change is moving climate conditions outside the range of past human experiences (IPCC, 2007b; Solomon et al., 2009). While previous experience in coping with climate variability or extremes can provide some valuable lessons for adapting to climate change, there are important differences between coping with variability and planning for climate change. Climate change has the potential to bring about abrupt changes that push the climate system across thresholds, creating novel condi- tions (Lenton et al., 2008). Likewise, thresholds in ecosystems (Adger et al., 2009; CCSP, 2009a) and human systems could be crossed, potentially overwhelming their adaptive capacity. The prospect that the climate system, ecosystems, or human systems may experience significant transitions to new states renders our previous experience an incomplete guide for future adaptation. For example, it is unclear whether managing natural ecosystems for resilience (i.e., assisting ecosystems to return to a previous natural  

A D A P T I N G T O T H E I M PA C T S O F C L I M AT E C H A N G E state after a disturbance) will remain a valid approach under future climate conditions, because ecosystems might cross thresholds into new steady states (West et al., 2009). Thus, managing certain ecosystems toward a new “natural” state might be a more viable strategy. Because of the potential for crossing such thresholds, adaptation to climate change begins with building adaptive capacities, frameworks, and institutional structures that can cope with future conditions that are beyond past experience. Adaptation requires maintaining a long-term perspective because there are consider- able uncertainties in estimating the nature, timing, and magnitude of climate impacts. This uncertainty involves the trajectory of future emissions and resulting changes in the mean climate conditions and the range of climate variability as well as other factors. Translating information at a global scale to local and regional scales can also contribute to uncertainty. Thus, precise predictions of many climate impacts are not available, despite the fact that the probability of some impacts is relatively high (e.g., loss of snowpack in the West and an ice-free Arctic in the summer). Adaptation to climate change calls for a new paradigm for considering a range of possible future climate conditions and associated changes in human systems and ecosystems, and for managing risks by recognizing prospects for departures from historical condi- tions, trends, and variation. This does not mean waiting until uncertainties have been reduced to consider adaptation actions, because there is a real risk that impacts could emerge too rapidly or too powerfully for delayed adaptations to reduce major disrup- tions to human and natural systems. Mobilizing now to increase the nation’s adaptive capacity can be viewed as an insurance policy against an uncertain future. (See Box 1.1 for definitions of key terms used in this report.) What Are the Risks? Across the vast area of the United States and islands located within U.S. territory, many regions, sectors, populations, or resources exhibit vulnerabilities to climate variations and change (Figure 1.1). A recent report of the U.S. Global Change Research Program (USGCRP) highlights the range of climate change impacts on the United States (2009). Areas of particular concern include low-lying coastlines, especially coastal areas of the Southeast that are susceptible to hurricanes, sea level rise, saltwater intrusion, and land subsidence; the West, where water supplies are largely dependent on snowpack, particularly those with little storage relative to annual flow; inner cities in the Midwest and Northeast, where many residents do not have access to air conditioning; natural ecosystems and native villages in northern Alaska that are subject to rapid changes in temperature, thawing of permafrost, and loss of sea ice; and Western forests that are susceptible to wildfire and bark beetle infestation. In the absence of adaptation,  

Introduction bOx 1.1 Definitions of Key Terms Adapt, Adaptation: Adjustment in natural or human systems to a new or changing environment that exploits beneficial opportunities or moderates negative effects. Adaptive Capacity: The ability of a system to adjust to climate change (including climate vari- ability and extremes) to moderate potential damages, to take advantage of opportunities, or to cope with the consequences. Resilience: A capability to anticipate, prepare for, respond to, and recover from significant multi- hazard threats with minimum damage to social well-being, the economy, and the environment. Risk: A combination of the magnitude of the potential consequence(s) of climate change impact(s) and the likelihood that the consequence(s) will occur. vulnerability: The degree to which a system is susceptible to, or unable to cope with, adverse effects of climate change, including climate variability and extremes. Vulnerability is a function of the character, magnitude, and rate of climate variation to which a system is exposed, its sensitivity, and its adaptive capacity. FIguRE 1.1 An illustration of the range of climate change impacts across the United States. SOURCE: International Mapping Associates.  

A D A P T I N G T O T H E I M PA C T S O F C L I M AT E C H A N G E the risks of negative consequences that could accompany these types of impacts are heightened. How Can We Adapt? Because impacts of and vulnerabilities to climate change vary greatly across regions and sectors, adaptation decisions are fundamentally place-based, occurring at mul- tiple scales, from that of the individual household or firm, to cities, regions, states, tribes, corporations, and economic sectors, to the level of the federal government and agencies within it that manage land and other resources. Considering the range, and in some instances the severity of climate change risks, it seems clear that capacities currently available for adaptation at the local and state levels are inadequate to ad- dress risks to health, well-being, property, and ecosystem services in many regions of the United States. While some localities and states have attempted to formulate adap- tation strategies, they often lack the information, resources, and decision-making tools to pursue these plans. Meanwhile, there is a growing recognition that a new collabora- tive national effort is needed in support of adaptation across all scales, nationally and internationally (GAO, 2009a; NRC, 2009a,b). Choices regarding how and when to adapt vary greatly. Adaptation could involve an immediate mobilization to reduce vulnerability to climate change and increase adap- tive capacity. Or adaptation could take the form of accepting, responding to, and living with impacts that could in many cases be disruptive of our lives and livelihoods. De- veloping a framework for selecting among these types of adaptation options is critical given that, in different locations or for different sectors, the same strategy may pro- duce very different results. This report identifies a number of choices that are available and outlines a method for selecting options based on a risk-management approach. Adaptation to climate change can be categorized as “autonomous” or “planned.” Autonomous adaptations are actions taken voluntarily by decision makers (such as farmers or city leaders) whose risk management is motivated by information, market signals, co-benefits, and other factors. Planned adaptations are interventions by gov- ernments to address needs judged unlikely to be met by autonomous actions—often adaptations larger in scale and/or resource requirements. The public sector plays important roles in both cases. Governments support autonomous adaptation by providing information, shaping market conditions through taxes and other policies (along with their own market decisions), and helping to enlarge portfolios of technol- ogies and other alternatives for decentralized actions. Governments can also act more 0 

Introduction directly by developing plans and strategies, providing resources, and undertaking projects (such as infrastructure development). What Are the Challenges and Opportunities? Research on how to adapt to the many changes in the climate system has lagged be- hind efforts to identify policies to limit GHG emissions for many reasons, including the perception that efforts to adapt might reduce the commitment to limiting GHGs and result in more challenges in the long term. One consequence has been that adapta- tion actions have not been widely considered, and knowledge about climate change adaptation has been incompletely developed. Reluctance to invest in adaptation research and actions is partly due to the fact that climate change is a slow-onset, multigenerational problem while decision makers tend to focus on short-term concerns and benefits. There is considerable empirical evidence suggesting that when individuals and businesses plan for the future, they do not fully weigh the long-term benefits of investing in loss-reduction measures, especially if there is only a small likelihood of reaping financial returns. The upfront costs of these protective measures loom disproportionately high relative to delayed expected ben- efits over time, especially given discount rates that are usually applied to most public and private investment. However, the tendency for people to focus on the short run and to ignore low-probability events below their threshold level of concern can have severe long-run consequences (Kunreuther and Michel-Kerjan, 2009). Because climate conditions by the later part of the 21st century will likely be outside the range of past human experiences, it is difficult to make decisions now about the full range of anticipated climate change impacts in 2050 or 2100. Policy makers will need to select options that are flexible enough not to inadvertently preclude other options that may be needed or become available in the future (Adger et al., 2009). An additional challenge is that climate change impacts are rarely the key drivers of vulnerability. Other factors determining vulnerability include existing inequalities, demographics, land use and economic changes, dwindling nonrenewable resources, public health, and institutional and technological change (IPCC, 2007a). Developing proactive strategies and planning processes that consider multiple perspectives, mul- tiple stressors, multiple time horizons related to intergenerational equity issues, and multiple competing interests is a complex challenge, calling for broad collaborations and partnerships. Despite these and other challenges, adaptation activities can produce many benefits that support other social objectives, such as sustainable development, public health,  

A D A P T I N G T O T H E I M PA C T S O F C L I M AT E C H A N G E economic competitiveness, national security, and international cooperation. Risk man- agement for climate change impacts often helps to address other stresses on human and natural systems as well, and attention to climate change adaptation aims and strategies can be a catalyst for increased attention to relatively long-term sustainabil- ity objectives and choices. SCOPE AND PuRPOSE OF THE REPORT This study and the overall America’s Climate Choices suite of activities respond to a request by the U.S. Congress for the National Oceanic and Atmospheric Administration (NOAA) to execute an agreement with the National Academy of Sciences to establish a committee that will “investigate and study the serious and sweeping issues relat- ing to global climate change and make recommendations regarding what steps must be taken and what strategies must be adopted in response to global climate change, including the science and technology challenges thereof.” This panel was charged to describe, analyze, and assess actions and strategies to reduce vulnerability, increase adaptive capacity, improve resilience, and promote successful adaptation to climate change in different regions, sectors, systems, and populations across the nation. The panel’s report draws on a wide range of sources and case studies to identify lessons learned from past experiences, promising current approaches, and potential new directions. The challenges of this panel’s assignment to “provide advice about what to do about adaptation” in the United States are numerous. The panel chose to provide a “menu” il- lustrating the long list of options available for consideration in adaptation planning for specific sectors. It uses the concept of risk management, broadly construed, to frame the process of planning and selecting approaches to climate change adaptation. The panel has outlined a number of principles for developing an adaptation strategy that addresses issues within the boundaries of the United States as well as in the interna- tional context. The decision to select a risk-management framework reflects an emerg- ing scientific consensus that the United States will not be able to eliminate all risks associated with climate change; however, if the nation prioritizes activities well, it will be possible to minimize negative impacts and maximize the opportunities associated with climate change. The decision also reflects the panel’s perspective that the needed actions involve limiting risks in the broadest sense—including risks associated with current and future political, economic, social, and environmental realities.  

Introduction PRINCIPLES TO guIDE CLIMATE CHANgE ADAPTATION This report views and discusses adaptation through the lens of long-term sustain- ability and emphasizes cross-sectoral integration and an inclusive approach, because adaptation choices are linked directly to choices about limiting GHG and sustainable use of resources. It also recognizes the inevitability of tradeoffs and value judgments associated with all adaptation choices (Adger et al., 2009; Anderies et al., 2004; Tainter, 2003). For example, it is a fact that climate change “involves harm to some—now and in the future—on the basis of gain to others (in the past, present and future)” (Adger et al., 2009). Therefore, adaptation choices and decisions require both a scientific assess- ment of impacts and socioeconomic vulnerabilities and an assessment of their sensi- tivity to values and political decisions. In preparing for its assignment, the panel recognized that its assessments and conclu- sions would be shaped by the values that its members brought to the group process. It chooses, therefore, to explicitly state the principles that guided the panel’s work and to offer them as a possible set of criteria by which adaptation plans, policies, and adap- tation options might be evaluated by others: 1. In making adaptation decisions, focus not only on optimizing conditions for the current generation, but also look several generations ahead and consider ways to reduce risk over time. Some adaptation decisions must be taken today, but planning needs to focus toward the future, when the risks from climate change will be greatest. It follows that we must guard against the possibility that current actions could actually exacerbate either exposure or sensitivity of future generations to these growing risks. 2. Account for the impacts of adaptation decisions on natural and social systems as well as on individuals, firms, government institutions, and infrastructure. For example, energy infrastructure, production processes, ecosystems, and emer- gency response capacity have complex and multiple interrelated components, yet their capacity to function needs to be protected and/or enhanced in the context of adaptation. The mechanisms established for ongoing evaluation of progress need to include assessments of effects on such synergistic systems. 3. Recognize that ecosystem structure and functioning are particularly vulnerable to climate change and need consideration in adaptation decisions. While human systems can use advanced technology and mobility to adapt, some ecosystem components are relatively limited in their ability to adapt to rapid rates of change. The intimate dependence of humans on the vital services provided by natural ecosystems needs to be recognized.  

A D A P T I N G T O T H E I M PA C T S O F C L I M AT E C H A N G E 4. Evaluate solutions from a perspective of sustainability so that social, economic, and environmental ramifications of proposed strategies and actions are explicitly recognized. Adaptation decisions should be integrated into the broader con- text of sustainable development. 5. Acknowledge equity and justice in adaptation decisions; there is a need to priori­ tize helping those with a higher degree of vulnerability to become more resilient. The capacity to adapt is a critical feature of the nation’s ability to respond to climate change. There are vulnerable populations and ecosystems in the nation, and their welfare is considered a high priority in adaptation actions. Likewise, while considering international investments, reducing risk and vul- nerability in other countries is considered a high priority. 6. There is a need to identify the potential impacts of proposed adaptation options on all affected parties. It is important to consider the expected costs and ben- efits from adaptation programs to those who are affected by them, including the potential for unintended consequences. 7. Develop a portfolio approach for addressing adaptation problems, including a suite of technology and social­behavioral­economic options. The same underly- ing reality that speaks to the need for diversification in the financial sector applies to climate change response strategies. 8. Develop methods of evaluation so that the risk of inactions can be compared with the risk of proposed actions. The implications of proposed actions for public policy need to be recognized and explored so that decision makers can clearly see tradeoffs expressed not only in terms of costs and benefits but also in terms of short- and long-term risks. 9. Recognize the international implications of U.S. adaptation and emissions­reduc­ tion efforts, as well as the impacts on the United States of decisions made by other countries. The success of U.S. adaptation and mitigation efforts is in large part dependent on cooperative efforts across the globe. ORgANIzATION OF THE REPORT Identifying adaptation options and strategies to respond to climate change requires an understanding of anticipated changes in temperature and other climate variables and how these will in turn affect economic sectors and natural and human systems. In Chapter 2, the panel explores the impacts of projected changes in temperature and precipitation on natural resources, infrastructure, human health, and the environment. The chapter also identifies the scientific challenges that remain in assessing climate change impacts and vulnerabilities for adaptation.  

Introduction Chapter 3 addresses the panel’s charge to identify short-term options for adapting to climate change at different government levels and in different sectors by examining ongoing domestic and international adaptation activities for lessons learned. A menu of options for adapting to climate variability and other stressors is provided for par- ticular decision needs in various sectors: ecosystems, agriculture and forestry, water, health, transportation, energy, and coastal regions. Furthermore, the chapter empha- sizes the importance of comprehensive strategies to address multiple stresses, to increase the efficient use of adaptation resources, and to avoid inadvertent maladap- tive actions. In Chapter 4, the report highlights impediments to adaptation and an approach to overcoming these challenges. The approach involves an adaptive risk-management framework combining a portfolio of adaptation and emissions-reduction strategies, all of which should include provisions for learning by doing. The report draws on the example of New York City’s adaptation efforts to illustrate how to develop an action- oriented adaptation strategy, principles for developing an adaptation plan, methods for selecting adaptation options, and tools and decision makers necessary for imple- menting an adaptation plan. Research needs to expand on adaptation opportunities are also identified. Chapter 5 addresses the panel’s charge to identify long-term strategies and oppor- tunities to adapt to climate change. It demonstrates that effective adaptation will require the development of the capacity to adapt, which includes not only infrastruc- ture and other investments but also more flexible institutions and investments in both adaptation processes and research on adaptation processes and outcomes. The chapter discusses the current lack of institutional capacity to build and implement an effective national adaptation effort, even to support the most vulnerable regions and sectors (those that are affected most immediately and severely by climate change). Because the nation lacks experience in and knowledge about how to adapt to rapid changes in the climate system, the chapter describes how adaptation capacity can be optimized through ongoing assessments of vulnerability and of the effectiveness of alternative adaptation options. Finally, Chapter 5 identifies the role of various decision makers at local, state, and federal government levels, as well as in the private sector, in building adaptive capacity and implementing climate change adaptation. Chapter 6 focuses on the opportunities and rationale for considering adaptation within the international context. U.S. relationships with other countries will be affected in numerous ways by choices made in regards to addressing national and interna- tional resilience to climate change and supporting adaptation in especially vulner- able areas. At a fundamental level, the decisions made by individual governments are  

A D A P T I N G T O T H E I M PA C T S O F C L I M AT E C H A N G E linked to impacts in other countries, through effects on the climate system, the global economy, and multiple other ways. The chapter concludes by highlighting the benefits of integrating climate change adaptation objectives into a range of foreign policy, development assistance, and capacity-building efforts, to improve the nation’s ability to influence a broader range of outcomes, including economic and national security considerations. Chapter 7 discusses the need for focused science and technology improvements to support adaptation activities, including evaluation of both gradual climate change and potential abrupt tipping points. It further elaborates on major challenges for adaptation research, including an improved understanding of human behavior affect- ing adaptation measures and how climate change adaptation relates to questions of sustainability. The chapter identifies a number of sector-specific adaptation options that would benefit from science and technology advances. Chapter 8 provides a summary of the panel’s conclusions and recommendations. The chapter emphasizes a need for broad-based national collaboration in planning and implementing adaptation actions, and it examines opportunities for near-term ac- tions that would enhance the nation’s adaptive capacity. This has profound meaning for both the near term and the long term. In the near term, America’s choices will be focused mainly on adaptation actions that reduce risks from climate change impacts while at the same time helping to meet other needs, such as reducing risks from climate variability or reducing threats that could undermine near-term economic and social development. The emphasis will be on how climate change adaptation offers co-benefits as it reduces vulnerabilities related to ecosystem stress, water resource management, community resilience, human health, energy security, and other social concerns. This report identifies a wide variety of possible adaptation actions, some of which represent relatively low net costs to decision makers in many locations and sectors and have the potential for co-benefits (Chapter 3), along with strategies for identifying and assessing such possible actions (Chapter 4) and opportunities for in- stitutional partnerships as the nation seeks to work together in its response to climate change impacts (Chapter 5). In the longer term, America’s choices will be focused mainly on three needs: (1) en- suring the development of adaptive institutions that continually consider further actions to cope with longer-term impacts and vulnerabilities, and also ensuring that these institutions are supported by systems that monitor emerging climate condi- tions and their effects and provide feedback about experiences with climate change adaptation (Chapters 4 and 5); (2) enlarging our range of choices by strengthening the science and technology that open new options for action and significantly improve  

Introduction our knowledge of their benefits, costs, potentials, and possible limits (Chapter 7); and (3) sharing the responsibility for supporting adaptation to climate change impacts in other areas of the world that are not capable of adapting on their own (Chapter 6). Through the pursuit of these near- and long-term adaptations, America can minimize harm and take advantage of opportunities that may result from a changing environ- ment while sustaining human welfare and ecological integrity.