Title: Building Resilience to Climate Change in Informal Settlements
Abstract: Approximately 1 billion people currently live in informal settlements, primarily in urban areas in low- and middle-income countries. Informal settlements are defined by poor-quality houses or shacks built outside formal laws and regulations. Most informal settlements lack piped water or adequate provision for sanitation, drainage, and public services. Many are on dangerous sites because their inhabitants have a higher chance of avoiding eviction. This paper considers how to build resilience to the impacts of climate change in informal settlements. It focuses on informal settlements in cities in low- and middle-income countries and how these concentrate at-risk populations. This paper also reviews what is being done to address climate resilience in informal settlements. In particular, community- and city-government-led measures to upgrade settlements can enhance resilience to climate-change risks and serve vulnerable groups. It also discusses how the barriers to greater scale and effectiveness can be overcome, including with synergies with the Sustainable Development Goals. Approximately 1 billion people currently live in informal settlements, primarily in urban areas in low- and middle-income countries. Informal settlements are defined by poor-quality houses or shacks built outside formal laws and regulations. Most informal settlements lack piped water or adequate provision for sanitation, drainage, and public services. Many are on dangerous sites because their inhabitants have a higher chance of avoiding eviction. This paper considers how to build resilience to the impacts of climate change in informal settlements. It focuses on informal settlements in cities in low- and middle-income countries and how these concentrate at-risk populations. This paper also reviews what is being done to address climate resilience in informal settlements. In particular, community- and city-government-led measures to upgrade settlements can enhance resilience to climate-change risks and serve vulnerable groups. It also discusses how the barriers to greater scale and effectiveness can be overcome, including with synergies with the Sustainable Development Goals. The current urban population is approximately 4.4 billion people globally. About 3.4 billion people currently live in urban centers in what the United Nations (UN) terms “less developed regions.”1UN Population DivisionWorld Urbanization Prospects 2018.https://population.un.org/wup/Date: 2018Google Scholar UN projections suggest that urban population growth in “less developed regions” will be over 2 billion people by 2050 and that close to 90% of this increase will be in Asia and Africa. This means that another 2 billion urban dwellers will require housing, basic services, and resilience to climate-change impacts.1UN Population DivisionWorld Urbanization Prospects 2018.https://population.un.org/wup/Date: 2018Google Scholar At present, approximately 1 billion urban dwellers live in what are termed informal settlements in poor-quality houses or shacks.2Revi A. Satterthwaite D. Aragón-Durand F. Corfee-Morlot J. Kiunsi R.B.R. Pelling M. Roberts D. Solecki W. Pahwa Gajjar S. Sverdlik A. Chapter 8: Urban areas in field.in: Field C.B. Barros V.R. Dokken D.J. Mach K.J. Mastrandrea M.D. Bilir T.E. Chatterjee M. Ebi K.L. Estrada Y.O. Genova R.C. 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. Cambridge University Press, 2014: 535-612Google Scholar Informal settlements fall outside formal laws and regulations on land ownership, land use, and buildings. Their illegality makes government agencies unable or unwilling to work with them. These are settlements to which city governments have not extended what the UN Intergovernmental Panel on Climate Change (IPCC) terms risk-reducing infrastructure (paved roads, storm and surface drainage, piped water, etc.) and services relevant to resilience (including healthcare, emergency services, and rules of law).2Revi A. Satterthwaite D. Aragón-Durand F. Corfee-Morlot J. Kiunsi R.B.R. Pelling M. Roberts D. Solecki W. Pahwa Gajjar S. Sverdlik A. Chapter 8: Urban areas in field.in: Field C.B. Barros V.R. Dokken D.J. Mach K.J. Mastrandrea M.D. Bilir T.E. Chatterjee M. Ebi K.L. Estrada Y.O. Genova R.C. 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. Cambridge University Press, 2014: 535-612Google Scholar Many informal settlements are ill prepared for climate change and face particularly high risks of floods and landslides as a result of poor-quality buildings and a lack of infrastructure to prevent flooding, withstand heavy storms, and cope with heat waves.2Revi A. Satterthwaite D. Aragón-Durand F. Corfee-Morlot J. Kiunsi R.B.R. Pelling M. Roberts D. Solecki W. Pahwa Gajjar S. Sverdlik A. Chapter 8: Urban areas in field.in: Field C.B. Barros V.R. Dokken D.J. Mach K.J. Mastrandrea M.D. Bilir T.E. Chatterjee M. Ebi K.L. Estrada Y.O. Genova R.C. 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. Cambridge University Press, 2014: 535-612Google Scholar In the absence of more effective policies, most of the world’s growth in urban population will be accommodated in informal settlements. Given the projected rates and regions of urban population growth by 2050, there is an urgent need to build resilience to climate change in these settlements and to do so at scale. There is also an urgent need to vastly expand the supply and reduce the cost of “formal” (i.e., legal) housing that provides low-income groups with safer and more accessible alternatives to informal settlements. The heterogeneity among informal settlements precludes agreement on a precise definition. The term “informal settlement” generally refers to urban settlements that develop outside the legal systems intended to record land ownership and tenure and enforce compliance with regulations relating to planning and land use, built structures, and public health and safety. The definition used by the Organization for Economic Co-operation and Development includes “areas where groups of housing units have been constructed on land that the occupants have no legal claim to or occupy illegally” and “unplanned settlements and areas where housing is not in compliance with current planning and building regulations (unauthorized housing).”3Organisation for Economic Co-operation and DevelopmentGlossary of Statistical Terms.https://stats.oecd.org/glossary/detail.asp?ID=1351Date: 2018Google Scholar Given their legal status, most governments do not collect data on informal settlements or their inhabitants. Censuses should be able to provide detailed data on informal settlements, but they would need to define informal settlements and include a field in the household census form for marking whether the household is living in an informal settlement.4Lilford R.J. Oyebode O. Satterthwaite D. Melendez-Torres G.J. Chen Y.-F. Mberu M. Watson S.I. Sartori J. Ndugwa R. Caiaffa W. et al.The health of people who live in slums 2; Improving the health and welfare of people who live in slums.Lancet. 2016; https://doi.org/10.1016/S0140-6736(16)31848-7Abstract Full Text Full Text PDF Scopus (129) Google Scholar Official household surveys (including the Demographic and Health Surveys Program of the US Agency for International Development) have sample sizes that are too small to be able to provide data on each urban area and each informal settlement.5Vlahov D. Agarwal S. Buckley R.M. Teixeira Caiaffa W. Corvalan C.F. Chika Ezeh A. Finkelstein R. Friel S. Harpham T. Hossain M. et al.Roundtable on urban living environment research (RULER).J. Urban Health. 2011; 88: 793-857Crossref PubMed Scopus (24) Google Scholar Despite the general lack of data, two sources of information support the estimate of approximately 1 billion people living in informal settlements. The first source is UN estimates that suggested 880 million “slum dwellers” in 2016.6UN-HabitatWorld Cities Report 2016: Urbanization and Development; Emerging Futures. United Nations Human Settlements Programme, 2016Google Scholar Most of these are likely to be in informal settlements, although informal settlements and slums are not necessarily the same. Informal settlements are defined according to contraventions of specific laws, rules, and regulations, whereas slums are usually defined on the basis of measures of housing quality, overcrowding, and the provision of urban services. The second source of information is city-level case studies that suggest that it is common for cities to have 30%–50% of their population in informal settlements,7Rojas E. No time to waste; applying the lessons from Latin America’s 50 years of housing policies to rapidly urbanizing countries.Environ. Urban. 2018; 31: 177-192Crossref Scopus (6) Google Scholar although some have a higher proportion—for instance, 60% in Nairobi,8African Population and Health Research CenterPopulation and Health Dynamics in Nairobi’s Informal Settlements: Report of the Nairobi Cross-sectional Slums Survey (NCSS) 2012.2014https://assets.publishing.service.gov.uk/media/57a089f240f0b64974000338/NCSS2-FINAL-Report.pdfGoogle Scholar,9Lines K. Makau J. Muungano nguvu yetu (unity is strength): 20 years of the Kenyan federation of slum dwellers.https://pubs.iied.org/pdfs/10807IIED.pdfDate: 2017Google Scholar 65% in Cairo,10Séjourné M. Kipper R. Fischer M. The History of Informal Settlements in Cairo’s Informal Areas between Urban Challenges and Hidden Potentials: Facts, Voices, Visions. GTZ Cairo, 2009Google Scholar and 70% in Dar es Salaam.11Kiunsi R. The constraints on climate change adaptation in a city with large development deficits: the case of Dar es Salaam City.Environ. Urban. 2013; 25: 321-337Crossref Scopus (38) Google Scholar A study in Mumbai notes that “over half of the city’s population lives in informal settlements of varying infrastructure, income, economy, ethnicity and religion, squeezed into whatever space can be found from bridges and railways to pavements and shantytowns” (p. 91).12McFarlane C. Sanitation in Mumbai’s informal settlements: state, ‘slum’ and infrastructure.Environ. Plann. A. 2008; 40: 88-107Crossref Scopus (148) Google Scholar One billion informal-settlement dwellers would represent 29% of the total urban population of low- and middle-income nations of 3.4 billion;1UN Population DivisionWorld Urbanization Prospects 2018.https://population.un.org/wup/Date: 2018Google Scholar therefore, this estimate is consistent with existing data. There are some detailed case studies of informal settlements13Moser C.O.N. Ordinary Families, Extraordinary Lives: Assets and Poverty Reduction in Guayaquil, 1978-2004. Brookings Institution, 2009Google Scholar,14Perlman J. Favela: Four Decades of Living on the Edge in Rio de Janeiro. University Press, 2010Google Scholar and some city-wide studies,15Karanja I. An enumeration and mapping of informal settlements in Kisumu, Kenya, implemented by their inhabitants.Environ. Urban. 2010; 22: 217-239Crossref Scopus (86) Google Scholar,16Livengood A. Kunte K. Enabling participatory planning with GIS: a case study of settlement mapping in Cuttack, India.Environ. Urban. 2012; 24: 77-97Crossref Scopus (43) Google Scholar but it is difficult to collect data on informal settlements. There is often hostility to outsiders asking questions, and these settlements often have no street names, street maps, or registered addresses for residents. Data scarcity therefore remains a central challenge. Although the response of many city governments to informal settlements is either to ignore them or to bulldoze them,2Revi A. Satterthwaite D. Aragón-Durand F. Corfee-Morlot J. Kiunsi R.B.R. Pelling M. Roberts D. Solecki W. Pahwa Gajjar S. Sverdlik A. Chapter 8: Urban areas in field.in: Field C.B. Barros V.R. Dokken D.J. Mach K.J. Mastrandrea M.D. Bilir T.E. Chatterjee M. Ebi K.L. Estrada Y.O. Genova R.C. 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. Cambridge University Press, 2014: 535-612Google Scholar some city governments have worked successfully with informal-settlement inhabitants on upgrading programs to secure tenure, improve housing, install needed infrastructure, and provide public services. Such upgrading programs generally focus on addressing current risks to informal-settlement inhabitants. This paper considers the extent to which these upgrading programs can enhance the resilience of informal settlements and their inhabitants to the impacts of climate change. Defining Climate Resilience in Informal Settlements discusses how a concern for resilience can be applied to informal settlements. Climate-Change Risks in Informal Settlements describes how and why these settlements face particularly high risks related to climate change. Building Climate Resilience in Informal Settlements and Building Resilience through Upgrading Initiatives review existing approaches to upgrading informal settlements, including community- and city-government-led measures, and the extent to which these serve vulnerable groups and enhance resilience to climate-change risks. Addressing Barriers to Upgrading discusses the barriers to greater scale and effectiveness of upgrading programs and how these might be overcome. Synergies with the Sustainable Development Goals considers the relevance of the Sustainable Development Goals (SDGs) to helping build resilience in informal settlements. The final Conclusions section draws some conclusions, including the need for new funding models that support city governments and other local actors to act upon upgrading programs that address climate-change risks. Within broader debates around climate-change adaptation, there has been growing interest in the resilience of cities and communities to the impacts of climate change. In the broadest sense, resilience is defined as the capacity or ability of something, someone, or some group to anticipate, accommodate, cope, adapt, or transform when exposed to specified hazards. The IPCC’s definition of resilience when applied to urban centers is the ability of urban centers (and their populations, enterprises, and governments) and the systems on which they depend to anticipate, reduce, accommodate, or recover from the effects of a hazardous event in a timely and efficient manner.2Revi A. Satterthwaite D. Aragón-Durand F. Corfee-Morlot J. Kiunsi R.B.R. Pelling M. Roberts D. Solecki W. Pahwa Gajjar S. Sverdlik A. Chapter 8: Urban areas in field.in: Field C.B. Barros V.R. Dokken D.J. Mach K.J. Mastrandrea M.D. Bilir T.E. Chatterjee M. Ebi K.L. Estrada Y.O. Genova R.C. 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. Cambridge University Press, 2014: 535-612Google Scholar There is much overlap between this and the 100 Resilient Cities initiative’s definition of urban resilience as the capacity of individuals, communities, institutions, businesses, and systems within a city to survive, adapt, and grow no matter what kinds of chronic stresses and acute shocks they experience.17ARUPCity Resilience Index.https://www.arup.com/perspectives/city-resilience-indexDate: 2014Google Scholar Thus, “city resilience describes the capacity of cities to function, so that the people living and working in cities—particularly the poor and vulnerable—survive and thrive no matter what stresses or shocks they encounter” (p. 11).17ARUPCity Resilience Index.https://www.arup.com/perspectives/city-resilience-indexDate: 2014Google Scholar In the context of these broader definitions of urban climate resilience, Figure 1 identifies specific resilience-building measures relevant to informal settlements. Figure 1 highlights the ways in which informal-settlement-upgrading programs can act to reduce hazards, reduce risk by reducing exposure to hazards, and increase resilience among vulnerable populations. Anticipatory adaptation by households can avoid or reduce climate-change-related risks, for instance, by living in a safe location, having a safe, structurally sound house, and having risk-reducing infrastructure. Reducing disaster risk is also anticipatory in its focus, and accommodating and recovering from a disaster seeks to “bounce back” to the previous state.18Shaw K. Theobald K. Resilient local government and climate change interventions in the UK.Local Environ. 2011; 16: 1-15Crossref Scopus (57) Google Scholar “Bouncing back” requires government capacity to rapidly restore key services and repair infrastructure. Bouncing forward, by contrast, is part of what the IPCC refers to as transformative adaptation, where urban centers have integrated their development, disaster-risk reduction, and climate-change-adaptation policies and investments within an understanding of the need for mitigation and sustainable ecological footprints (as discussed in the Conclusions section). There are limits to adaptation, however. As noted in Figure 1, certain hazards in informal settlements cannot be addressed by upgrading programs.19Oppenheimer M. Campos M. Warren R. Birkmann J. Luber G. O’Neill B. Takahashi K. Emergent risks and key vulnerabilities.in: Field C.B. Barros V.R. Dokken D.J. Mach K.J. Mastrandrea M.D. Bilir T.E. Chatterjee M. Ebi K.L. Estrada Y.O. Genova R.C. 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. Cambridge University Press, 2014: 1039-1099Google Scholar Flood risks that require watershed management in the wider region, far beyond a settlement’s boundaries and the scope of its upgrading programs, would be one such example. There are also the residual risks that remain after all the measures to reduce hazards and risks and to address the needs of vulnerable populations. For informal settlements, there is a need to enhance climate resilience at different scales and with a range of different measures. The different scales are individuals or households (and their homes, assets, and livelihoods), neighborhoods, settlements, settlement-city links, and settlement-city-regional links. For each of these scales, mixes of measures to anticipate, reduce, accommodate, and recover exist to serve vulnerable groups. The settlement-city-region links are especially important because resilience to many climate-change impacts within informal settlements depends on city-wide infrastructure. For instance, flood control and management within a settlement can depend on infrastructure outside settlement boundaries. Land-use management in and around the city scale also has relevance to associated informal settlements. Most of the measures needed to build city resilience to climate change are within the responsibilities of their governments. But in cities with infrastructure deficits and a substantial proportion of their population in informal settlements, risk and vulnerability are often highly concentrated in these settlements; many are on floodplains alongside rivers or on steep slopes.2Revi A. Satterthwaite D. Aragón-Durand F. Corfee-Morlot J. Kiunsi R.B.R. Pelling M. Roberts D. Solecki W. Pahwa Gajjar S. Sverdlik A. Chapter 8: Urban areas in field.in: Field C.B. Barros V.R. Dokken D.J. Mach K.J. Mastrandrea M.D. Bilir T.E. Chatterjee M. Ebi K.L. Estrada Y.O. Genova R.C. 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. Cambridge University Press, 2014: 535-612Google Scholar These are settlements to which city governments have not extended risk-reducing infrastructure and services relevant to resilience. Here it falls to individuals, households, and community organizations to address these issues without external support. Reviewing the five IPCC Global Assessments undertaken since 1990 reveals that over time, there has been increasing attention to cities for both climate-change adaptation and mitigation. The IPCC Fifth Assessment Report (Working Group II) was notable for being the first global assessment to have a chapter focusing only on urban areas and for having more detailed coverage of cities than the previous assessments—in large part because the Fifth Assessment Report contained much more source literature on cities and climate change.2Revi A. Satterthwaite D. Aragón-Durand F. Corfee-Morlot J. Kiunsi R.B.R. Pelling M. Roberts D. Solecki W. Pahwa Gajjar S. Sverdlik A. Chapter 8: Urban areas in field.in: Field C.B. Barros V.R. Dokken D.J. Mach K.J. Mastrandrea M.D. Bilir T.E. Chatterjee M. Ebi K.L. Estrada Y.O. Genova R.C. 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. Cambridge University Press, 2014: 535-612Google Scholar This chapter on urban areas notes how “urban climate change risks, vulnerabilities, and impacts are increasing across the world in urban centers of all sizes, economic conditions, and site characteristics” and how “much of key and emerging global climate risks are concentrated in urban areas” (p. 538).2Revi A. Satterthwaite D. Aragón-Durand F. Corfee-Morlot J. Kiunsi R.B.R. Pelling M. Roberts D. Solecki W. Pahwa Gajjar S. Sverdlik A. Chapter 8: Urban areas in field.in: Field C.B. Barros V.R. Dokken D.J. Mach K.J. Mastrandrea M.D. Bilir T.E. Chatterjee M. Ebi K.L. Estrada Y.O. Genova R.C. 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. Cambridge University Press, 2014: 535-612Google Scholar It also notes how “rapid urbanization and rapid growth of large cities in low- and middle-income countries have been accompanied by the rapid growth of highly vulnerable urban communities living in informal settlements, many of which are on land at high risk from extreme weather” (p. 538).2Revi A. Satterthwaite D. Aragón-Durand F. Corfee-Morlot J. Kiunsi R.B.R. Pelling M. Roberts D. Solecki W. Pahwa Gajjar S. Sverdlik A. Chapter 8: Urban areas in field.in: Field C.B. Barros V.R. Dokken D.J. Mach K.J. Mastrandrea M.D. Bilir T.E. Chatterjee M. Ebi K.L. Estrada Y.O. Genova R.C. 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. Cambridge University Press, 2014: 535-612Google Scholar Urban climate-change-related risks include “… rising sea levels and storm surges, heat stress, extreme precipitation, inland and coastal flooding, landslides, drought, increased aridity, water scarcity, and air pollution with widespread negative impacts on people (and their health, livelihoods, and assets) and on local and national economies and ecosystems” (p. 538).2Revi A. Satterthwaite D. Aragón-Durand F. Corfee-Morlot J. Kiunsi R.B.R. Pelling M. Roberts D. Solecki W. Pahwa Gajjar S. Sverdlik A. Chapter 8: Urban areas in field.in: Field C.B. Barros V.R. Dokken D.J. Mach K.J. Mastrandrea M.D. Bilir T.E. Chatterjee M. Ebi K.L. Estrada Y.O. Genova R.C. 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. Cambridge University Press, 2014: 535-612Google Scholar The report further notes that “these risks are amplified for those who live in informal settlements and in hazardous areas and either lack essential infrastructure and services or where there is inadequate provision for adaptation” (p. 538).2Revi A. Satterthwaite D. Aragón-Durand F. Corfee-Morlot J. Kiunsi R.B.R. Pelling M. Roberts D. Solecki W. Pahwa Gajjar S. Sverdlik A. Chapter 8: Urban areas in field.in: Field C.B. Barros V.R. Dokken D.J. Mach K.J. Mastrandrea M.D. Bilir T.E. Chatterjee M. Ebi K.L. Estrada Y.O. Genova R.C. 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. Cambridge University Press, 2014: 535-612Google Scholar These concerns were further amplified by the Summary for Urban Policymakers prepared by IPCC authors advised by city practitioners and policymakers,20Bazaz A. Bertoldi P. Buckeridge M. Cartwright A. de Coninck H. Engelbrecht F. Jacob D. Hourcade J.-C. Klaus I. de Kleijne K. et al.Summary for urban policymakers—what the IPCC Special Report on Global Warming of 1.5°C means for cities. Indian Institute for Human Settlements, 2018https://doi.org/10.24943/SCPM.2018Crossref Google Scholar drawing on the IPCC Special Report on Global Warming of 1.5°C.21Intergovernmental Panel on Climate ChangeSummary for policymakers.in: Masson-Delmotte V. Zhai P. Pörtner O.-H. Roberts D. Skea J. Shukla P.R. Pirani A. Moufouma-Okia W. Péan C. Pidcock R. Global Warming of 1.5°C. An IPCC Special Report on the impacts of global warming of 1.5°C above pre-industrial levels and related global greenhouse gas emission pathways, in the context of strengthening the global response to the threat of climate change, sustainable development, and efforts to eradicate poverty. World Meteorological Organization, 2018Google Scholar This summarizes the impacts of the average temperature warming: human death and illness are expected to increase in pathways with warming greater than 1.5°C as a result of risks directly attributable to climate change, such as exacerbated urban heat islands, amplification of heat waves, extreme weather volatility, floods, droughts, coastal inundation, and an increase in vector-borne diseases such as malaria and dengue fever.20Bazaz A. Bertoldi P. Buckeridge M. Cartwright A. de Coninck H. Engelbrecht F. Jacob D. Hourcade J.-C. Klaus I. de Kleijne K. et al.Summary for urban policymakers—what the IPCC Special Report on Global Warming of 1.5°C means for cities. Indian Institute for Human Settlements, 2018https://doi.org/10.24943/SCPM.2018Crossref Google Scholar,21Intergovernmental Panel on Climate ChangeSummary for policymakers.in: Masson-Delmotte V. Zhai P. Pörtner O.-H. Roberts D. Skea J. Shukla P.R. Pirani A. Moufouma-Okia W. Péan C. Pidcock R. Global Warming of 1.5°C. An IPCC Special Report on the impacts of global warming of 1.5°C above pre-industrial levels and related global greenhouse gas emission pathways, in the context of strengthening the global response to the threat of climate change, sustainable development, and efforts to eradicate poverty. World Meteorological Organization, 2018Google Scholar Impacts on natural systems—including the degradation of natural systems and the loss of species with repercussions for regional and global food security, forests, and water systems—will also affect urban centers. There are also knowledge gaps on impacts at 2.0°C of warming compared with 1.5°C; these include “effects at the local level, as well as linkages between climate risks, poverty, equity, and well-being” (p. 11).20Bazaz A. Bertoldi P. Buckeridge M. Cartwright A. de Coninck H. Engelbrecht F. Jacob D. Hourcade J.-C. Klaus I. de Kleijne K. et al.Summary for urban policymakers—what the IPCC Special Report on Global Warming of 1.5°C means for cities. Indian Institute for Human Settlements, 2018https://doi.org/10.24943/SCPM.2018Crossref Google Scholar The IPCC’s Fifth Assessment Report emphasized the large spectrum in the capacity of urban centers to address resilience issues,2Revi A. Satterthwaite D. Aragón-Durand F. Corfee-Morlot J. Kiunsi R.B.R. Pelling M. Roberts D. Solecki W. Pahwa Gajjar S. Sverdlik A. Chapter 8: Urban areas in field.in: Field C.B. Barros V.R. Dokken D.J. Mach K.J. Mastrandrea M.D. Bilir T.E. Chatterjee M. Ebi K.L. Estrada Y.O. Genova R.C. 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. Cambridge University Press, 2014: 535-612Google Scholar as summarized in Figure 2. In high-income nations, almost all of the urban population is in homes that include the IPCC’s list of risk-reducing infrastructure and services. Most housing meets building regulations, which contributes to resilience and provides a base on which it can be increased. By contrast, much of the urban population in low- and many middle-income nations lives in informal settlements in homes that are not structurally sound and neighborhoods with little or no risk-reducing infrastructure or services. Figure 2 indicates that some cities have sufficient climate resilience and a capacity to “bounce forward” to greater resilience after a hazardous event.2Revi A. Satterthwaite D. Aragón-Durand F. Corfee-Morlot J. Kiunsi R.B.R. Pelling M. Roberts D. Solecki W. Pahwa Gajjar S. Sverdlik A. Chapter 8: