15 Key Takeaways for Cities, Settlements and Key Infrastructure from the IPCC AR6 WGII Climate Report 2022

by Timon McPhearson, Lead Author IPCC WGII

Climate change is a threat multiplier: Climate hazards interact with urban development to drive vulnerability and risks in cities. Impacts and risks will very likely increase for the next two decades and risks from 2050 onward could be severe if warming is not limited to 1.5°C.

It is the poorest and marginalized who are the most vulnerable: Currently 4.2 billion people live in cities and two-thirds of the world are projected to live in cities by 2050, making them hotspots of human risk. Adaptation that reduces risks and impacts will need to be targeted for those who need it most to safeguard urban lives and livelihoods.

Coastal cities are at risk: More than a billion people living in low-lying cities and settlements by 2050 may be at risk from coastal-specific climate hazards. Sea level rise and increases in tropical cyclone storm surge and rainfall intensity will increase the probability of coastal city flooding.

Extreme heat could affect many urban areas: The majority of the population exposed to heat waves will live in urban centers. Globally up to 16 times as many people may be exposed to extreme heat in the future. Deep and rapid cuts in carbon emissions are paramount and must happen in the next 10 years, otherwise we will have even less ability to adapt.

Drought and water scarcity may increase: 350 million people living in urban areas may be exposed to water scarcity from severe droughts at 1.5°C warming, and even more (410 million) at warming of 2°C. Limiting warming to 1.5°C is essential to avoid more severe impacts.

Impacts will be widespread: Projected impacts will not only reduce the prospects of sustainable development, but IPCC also projects an increase in poverty and inequality as well as increased involuntary migration of people due to climate change. We expect climate-driven increases in the frequency and strength of regional wildfires, increased floods and droughts, and an increase in temperature-related incidences of vector-borne, water-borne and food-borne diseases.

Adaptation may be limited in some areas: Especially in rapidly growing towns and cities and smaller settlements including those without dedicated local government. Infrastructure already built in large and mega-cities, designed without taking climate change risk into account, creates path dependency which may constrain innovation and lead to stranded assets and with increasing numbers of people unable to avoid climate impacts.

Multiple climate hazards will occur simultaneously more often: They may reinforce each other and result in increased impacts and risks to nature and people that are more complex and more difficult to manage. For example, reductions in crop yields due to heat and drought, made worse by reduced productivity because of heat stress among farmworkers, will increase food prices, reduce household incomes and lead to health risks from malnutrition, as well as climate-related deaths, especially in tropical regions. These impacts can impact global supply chains affecting many regions and cities.

What can we do? Start with conserving and protecting biodiversity: Nature-based solutions and ecosystem-based adaptation are now mainstream urban adaptation options and can be expanded through conservation, restoration, and protection as a key part of building climate resilience in urban areas. Adapting physical infrastructure will be also key to adapt to heat, flooding, and other climate impacts and extreme events.

Protect the most marginalized: Intersectional, gender-responsive and inclusive action can accelerate transformative climate change adaptation. The greatest gains in well being in urban areas can be achieved by prioritizing investment to reduce climate risk for low-income and marginalized residents and targeting informal settlements. Providing opportunities for marginalized people, including women, to take on leadership and participation in local projects can enhance climate governance and its outcomes.

Participation is key to equity: Participatory planning for infrastructure provision and risk management to address climate change and underlying drivers of risk in informal and under-serviced neighborhoods, the inclusion of Indigenous Knowledge and Local Knowledge, communication and efforts to build local leadership especially amongst women and youth are examples of inclusive approaches to adaptation that can also have co-benefits for equity.

It’s about policy, planning, and management: Addressing the gaps between policy and action requires managing social infrastructure such as community facilities, services and networks to address complex interconnected risks for example. City and local governments can invest directly in adaptation and work in partnership with community, private sector and national agencies to address climate risk. Private and business investment in key infrastructure, housing construction and through insurance requirements can also drive widespread adaptive action.

Adaptation must be a priority: 90% of climate finance is for mitigation. To successfully secure our own future and the future of the coming generations, climate risks must be factored into every decision, design, and plan. Climate impacts and risks can be substantially reduced by taking urgent action to limit global warming and strengthening adaptation efforts. This includes protecting and conserving nature, while improving planning and management of cities. Adaptation requires similar levels of investment to protect urban lives and livelihoods, especially for the most vulnerable.We already have the necessary technology, knowledge, and tools. But we have a rapidly closing window to bring total mean warming to 1.5 degrees or below, and will likely overshoot that in the next couple decades.

Cities can be solutions: Cities are hotspots for climate impacts and risks — because of the way they concentrate people, infrastructure and economies and they are growing fast. This growth however provides a global opportunity to build climate resilience into future urban development with cities leading the way for climate resilient development.

It’s about our youth: The youth climate movement and many NGOs have raised public awareness of climate and its impacts. We must consider future generations in every decision, design and plan. We have the knowledge and tools to transform cities and urban regions for climate resiliency, but must act now!

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About the IPCC Climate Report 2022

In February 2022, the Intergovernmental Panel on Climate Change (IPCC) released a historic report, “AR6 Climate Change 2022: Impacts, Adaptation and Vulnerability”, based on the contributions from Working Group II. The report assesses the impacts of climate change and options for adapting to it. The report includes Chapter 6: Cities, Settlements and Key Infrastructure, which considers the vulnerabilities and capacity of natural and human systems to adapt to climate change as well as options for creating a sustainable future through an equitable and integrated approach to both mitigation and adaptation. To read the full report click here.

Dr. Timon McPhearson is the Director of the Urban Systems Lab and professor of Urban Ecology at The New School. In 2018 he was appointed as a member of the Intergovernmental Panel on Climate Change (IPCC) and lead author for the urban chapter. He is also a Research Fellow at the Cary Institute of Ecosystem Studies in Millbrook, New York, and at the Stockholm Resilience Center at Stockholm University in Sweden.

Follow him on ResearchGate, Google Scholar, and LinkedIn.

Citation: Dodman, D., B. Hayward, M. Pelling, V. Castan Broto, W. Chow, E. Chu, R. Dawson, L. Khirfan, T. McPhearson, A. Prakash, Y. Zheng, and G. Ziervogel. (2022). Cities, Settlements and Key Infrastructure. In: Climate Change 2022: Impacts, Adaptation, and Vulnerability. Contribution of Working Group II to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change [H.-O. Pörtner, D.C. Roberts, M. Tignor, E.S. Poloczanska, K. Mintenbeck, A. Alegría, M. Craig, S. Langsdorf, S. Löschke, V. Möller, A. Okem, B. Rama (eds.)]. Cambridge University Press.