Cities and Climate Change

Climate change will affect all countries and, to varying degrees, both rural and urban areas. However, towns and cities are concentrations of population and economically and socially valuable assets and services.   For this reason, both the scale and cost of impacts, whether climate related or natural disaster related, tend to be disproportionately greater than in the more dispersed rural areas. Cities also tend to have large informal settlements built with little regard to official zoning and building standards.  Towns and cities often have high concentrations of solid and liquid wastes, large areas of impermeable surfaces such as roads that accelerate runoff and disrupt natural drainage patterns and are frequently co-located with hazardous industrial sites (chemical and oil refineries, for example), and toxic pollution which may cause major health disasters if damaged due to conflict, storm or other damaging events. 

On the other hand, the population concentration and infrastructure of towns and cities can facilitate the implementation of some adaptation and disaster prevention policies and measures.  While we discuss both climate change and disaster management together in this section, there are, of course, disasters unrelated to climate change (tectonic events, volcanoes, man-made disasters) as well as natural events made worse by climate change (for example, severe storms, drought, extreme heat events). In addition, some climate mitigation measures may be useful for natural disasters (for example, those related to extreme weather events); many others pertain to reducing carbon emissions through energy efficiency or fuel and power generation source substitution. Finally, urban centers are often particularly vulnerable to climate change and natural disaster-related impacts because they are often located on sea coasts, flood plains and other areas highly exposed to extreme events like storms and floods. 

Anticipated climate change impacts on cities are beginning to change how urban infrastructure is designed and located, populations are settled and the some city services are organized, as discussed previously. The principal climate change impacts include sea level rise, temperature rise, increased variability in precipitation patterns, and an increase in the frequency and/or severity of extreme weather events.  Climate change adaptation and disaster risk management require that the resilience of cities be improved. Retrofitting existing urban infrastructure and shelter and designing future urban services and shelter can enhance climate change preparedness and development.  This necessitates including adaptation and preparedness in sustainable urban growth.

The Intergovernmental Panel on Climate Change (IPCC) and the UN Framework Convention on Climate Change (UNFCCC), along with leading multilateral and bilateral donors and NGOs, have led the way in helping the world’s governments develop strategies and action programs for adaptation to climate change and mitigating their impacts. Planning now needs to be based not only on historical patterns but on predictions and projections of future impacts 30 to 50 years from now. Climate change will seriously impact the physical basis (such as land and water) for the provision of shelter and urban services as well as the location of populations. When climate change adaptation and disaster management become integrated into urban management, urban development and infrastructure will become more sustainable.

Reducing the carbon footprint of cities is an urban development imperative. Cities need to address and support renewable energy policies and investment opportunities as part of urban infrastructure development. Creating and implementing regulations and incentives on transport, industrial and power generation emissions, and efficiency standards are required to increase the use of renewables, alternative fuels and alternative transport modalities. Investing in environmental improvements will require building capacity in local government to understand and support clean production and energy efficiency and green building development. Urban environmental management includes water conservation, solid waste collection and disposal, control of air pollution, and sanitation, all of which impact the carbon footprint of cities.  Collectively, these mitigation measures can be part of a comprehensive low emissions development strategy (LEDS).  The biggest gains from LEDS for some countries will come from avoided deforestation, but for those with major urban and industrial “carbon footprints”, a wide range of efficiency and substitution measures will provide significant benefits.  In most if not all cases, mitigation measures focused on energy efficiency are also the most cost-effective.[1]

Disaster risk management (DRM) is now an important part of urban management in many countries. Recent disasters have reinforced just how vulnerable cities are and the need for local and national governments to be better prepared. USAID is in a unique position to work with local governments as partners to prepare and consolidate a city’s information base for planning and growth. DRM can shift from reactive relief efforts to pro-active preparedness initiatives and become one of several tools for climate change adaptation assessment, planning and prioritization of actions. Disaster risk management should be part of pro-active national and municipal planning to design and implement investments in adaptation measures and natural disaster prevention.

 The practical application of climate change impact assessments and projections as part of a city’s information base can guide retrofit and future growth requirements while also building public participation in adaptation measures and practices. The development of best practices addressing climate change adaptation, including those requiring transboundary (for example, regional flood control schemes) or trade-related measures will also be important topics for regional cooperation. Other topics for regional cooperation include early warning systems similar in concept to the way Famine Early Warning Systems and Geographic Information Systems exchange information.  Other adaptation-related measures may serve dual purposes in terms of disaster risk reduction including infrastructure such as flood control schemes, raised walkways, development of safe havens, escape routes, site preparation and the delivery of services through segmented infrastructure systems designed to reduce the severity of disaster impacts when and as events occur.

The investment requirements for designing and building high- and medium-rise, mixed-use urban structures incorporating “green building” standards are an important component of promoting a city's resiliency. Such structures represent a major shift in the current trends of urbanization in most developing countries. A higher-density, multi-family urban development model contrasts with the current sprawl and low-density development that characterize much urban growth. Sprawl is economically inefficient, frequently is associated with high carbon emissions from both transport and housing, and requires additional and costly water, sewerage and other infrastructure investments, which may distort the design, cost and delivery of basic urban services and sometimes reduce the area available for carbon sequestration (through reforestation). Informed local government strategies can support shelter and urban service delivery through the efficiencies that resilient planning brings. Well-organized and effectively managed cities that integrate measures such as improved land use planning, public transportation, improved water and sanitation systems, and updated building codes can dramatically cut GHG emissions, build resiliency to climate impacts, and promote improved health and sustainable development. More efficient cities (that is, those that encourage more water- and energy-efficient infrastructure, improved land use patterns, and “greener” buildings) can reduce emissions while saving money.

The U.S. Conference of Mayors (USCM) is a strong advocate for addressing climate change and as of November 5, 2010, 1044 cities have signed on to the U.S. Mayors’ Climate Change Agreement that pledges to reduce carbon dioxide emissions by 7 percent below 1990 levels by 2012. The USCM should be an important partner for USAID. The Agency’s support for exchange programs between US mayors and local governments in developing countries can adapt these programs and apply lessons learned to fit national and local social, financial and political urban contexts and conditions. An active member of the USCM stated that his program was a “no-regrets” effort, meaning that if climate change never happened what was being implemented was just sound urban management that should happen anyway. [2]

Investing in Climate Change Adaptation.  Adaptation investments range from public education and awareness, to economic and other incentives to address climate -induced constraints to production and livelihoods, to alternative settlements and new infrastructure. Activities should address the following questions: (i) how prepared are city officials and citizens to deal with urban infrastructure needs for future growth that incorporate climate adaptation requirements?; (ii) do city officials and citizens understand their roles and responsibilities vis-à-vis those of regional and national governments?; (iii) to what extent have citizens been actively engaged in the development and implementation of climate adaptation and mitigation measures?; and (iv) how are lessons learned from other experiences being applied in the local context? (for example, through knowledge sharing among peer professionals, NGOs and others).

Resilient and sustainable urban initiatives are opportunities to engage development partners in addressing issues that surround shelter and urban infrastructure, specifically access, maintenance, and expansion. Resilient, livable cities are those that are structured to manage their hazards for continued growth and that implement practices that will allow them to successfully adapt to climate change. Investing in adaptation can enhance resilience through early warning systems for episodic and cyclical extreme events, shelter and urban infrastructure development, and access to credit to finance the necessary investments. Resilience and livability are created and maintained by the quality of urban governance. Climate change impacts will affect the security and operational efficiency of shelter and basic urban services, especially in coastal areas and on steep slopes.  As noted previously, many preventive practices and investments to reduce carbon emissions and to improve operational efficiency of infrastructure and services may also be highly cost-effective as well.