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16 — Adaptation Opportunities, Constraints, and Limits Adaptation Opportunities, 16 Constraints, and Limits Coordinating Lead Authors: Richard J.T. Klein (Sweden), Guy F. Midgley (South Africa), Benjamin L. Preston (USA) Lead Authors: Mozaharul Alam (Bangladesh), Frans G.H. Berkhout (Netherlands), Kirstin Dow (USA), M. Rebecca Shaw (USA) Contributing Authors: Wouter Botzen (Netherlands), Halvard Buhaug (Norway), Karl W. Butzer (USA), E. Carina H. Keskitalo (Sweden), Yu’e Li (China), Elena Mateescu (Romania), Robert Muir-Wood (UK), Johanna Mustelin (Finland/Australia), Hannah Reid (UK), Lauren Rickards (Australia), Sarshen Scorgie (South Africa), Timothy F. Smith (Australia), Adelle Thomas (Bahamas), Paul Watkiss (UK), Johanna Wolf (Germany/Canada) Review Editors: Habiba Gitay (Australia), James Thurlow (South Africa) Volunteer Chapter Scientists: Seraina Buob (Switzerland), Adelle Thomas (Bahamas) This chapter should be cited as: Klein , R.J.T., G.F. Midgley, B.L. Preston, M. Alam, F.G.H. Berkhout, K. Dow, and M.R. Shaw, 2014: Adaptation opportunities, constraints, and limits. In: Climate Change 2014: Impacts, Adaptation, and Vulnerability. Part A: Global and Sectoral Aspects. Contribution of Working Group II to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Field, C.B., V.R. Barros, D.J. Dokken, K.J. Mach, M.D. Mastrandrea, T.E. Bilir, M. Chatterjee, K.L. Ebi, Y.O. Estrada, R.C. Genova, B. Girma, E.S. Kissel, A.N. Levy, S. MacCracken, P.R. Mastrandrea, and L.L. White (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, pp. 899-943. 899 Table of Contents Executive Summary ............................................................................................................................................................ 902 16.1. Introduction and Context ....................................................................................................................................... 904 16.1.1. Summary of Relevant AR4 Findings .................................................................................................................................................. 904 16.1.2. Summary of Relevant SREX Findings ................................................................................................................................................ 905 16.2. A Risk-Based Framework for Assessing Adaptation Opportunities, Constraints, and Limits ................................. 905 Box 16-1. Definitions of Adaptation Opportunities, Constraints, and Limits .............................................................................. 907 16 16.3. Adaptation Opportunities and Constraints ............................................................................................................ 908 16.3.1. Adaptation Opportunities ................................................................................................................................................................. 908 16.3.1.1. Enabling Conditions for Adaptation .................................................................................................................................. 908 Box 16-2. A Case Study of Opportunities for Adaptation and Disaster Risk Reduction .................................................. 910 16.3.1.2. Ancillary Benefits of Adaptation ........................................................................................................................................ 910 16.3.2. Adaptation Constraints ..................................................................................................................................................................... 911 16.3.2.1. Knowledge, Awareness, and Technology Constraints ......................................................................................................... 911 Box 16-3. Rates of Change as a Cross-Cutting Constraint ............................................................................................... 912 16.3.2.2. Physical Constraints .......................................................................................................................................................... 913 16.3.2.3. Biological Constraints ........................................................................................................................................................ 913 16.3.2.4. Economic Constraints ........................................................................................................................................................ 914 16.3.2.5. Financial Constraints ......................................................................................................................................................... 914 16.3.2.6. Human Resource Constraints ............................................................................................................................................ 915 16.3.2.7. Social and Cultural Constraints .......................................................................................................................................... 915 16.3.2.8. Governance and Institutional Constraints ......................................................................................................................... 916 16.3.2.9. Constraints and Competing Values .................................................................................................................................... 917 16.3.2.10. Consideration of Cross-Scale Dynamics ........................................................................................................................... 918 16.4. Limits to Adaptation ............................................................................................................................................... 919 16.4.1. Hard and Soft Limits ......................................................................................................................................................................... 919 Box 16-4. Historical Perspectives on Limits to Adaptation ......................................................................................................... 920 16.4.2. Limits and Transformational Adaptation ........................................................................................................................................... 921 16.5. Sectoral and Regional Synthesis ............................................................................................................................. 922 16.5.1. Sectoral Synthesis ............................................................................................................................................................................. 922 16.5.2. Regional Synthesis ............................................................................................................................................................................ 922 900 Adaptation Opportunities, Constraints, and Limits Chapter 16 16.6. Effects of Mitigation on Adaptation Opportunities, Constraints, and Limits ......................................................... 924 16.7. Ethical Dimensions of Adaptation Opportunities, Constraints, and Limits ............................................................. 925 16.8. Seizing Opportunities, Overcoming Constraints, and Avoiding Limits ................................................................... 927 References ......................................................................................................................................................................... 927 Frequently Asked Questions 16 16.1: What is the difference between an adaptation barrier, constraint, obstacle, and limit? .................................................................... 906 16.2: What opportunities are available to facilitate adaptation? ............................................................................................................... 908 16.3: How does greenhouse gas mitigation influence the risk of exceeding adaptation limits? ................................................................ 924 901 Chapter 16 Adaptation Opportunities, Constraints, and Limits Executive Summary Risk-based approaches to decision making provide a useful foundation for assessing the potential opportunities, constraints, and limits associated with adaptation of human and natural systems ( medium evidence , high agreement ). Risk management frames the consequences of climate change and potential adaptation responses in the context of actors’ values, objectives, and planning horizons as they make decisions under uncertainty. Adaptation planning and implementation are therefore contingent on actors’ perceptions of risk. Some risks may be routine and/or the consequences so minor that they are accepted. Other risks may be judged intolerable because they pose fundamen tal threats to actors’ objectives or the sustainability of natural systems. A key objective of adaptation is to avoid such intolerable risks. Yet, the capacity of societal actors and natural systems to adapt is finite, and thus there are limits to adaptation. {16.2, 16.3.2, 16.4, Box 16-1} Understanding of how the adaptive capacity of societal actors and natural systems influences the potential for adaptation to effectively manage climate risk has improved since the Fourth Assessment Report (AR4; very high confidence ). Adaptive capacity is influenced by actors’ abilities to capitalize on available opportunities that ease the planning and implementation
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