Cities and Climate Change: Introduction
Cities and Climate Change is a series of articles, where we are exploring how cities and urban areas are affected by the climate crisis. Besides introducing the challenges cities are facing, our aim is also to discover how cities can be the drivers of change. Therefore, each article will also focus on discovering solutions and best practices of enhancing cities’ resilience, too.
Lately - as a result of the increasing awareness of climate change - the recognition of the human impact on the environment is becoming widely accepted. Anthropogenic effects take shape generally in overpopulation, pollution, burning fossil fuels and deforestation (National Geographic) resulting in droughts, water scarcity, wildfires, increasing sea levels, flooding and extreme weather events, and decline of biodiversity as well (UN-Climate Action). These events are affecting our lives often more than we usually realise, cities and urban populations are no exception. Urban population is constantly growing, over 56% of the world's population live in cities and urban areas in 2021. Additionally, the share of the urban population is even higher in developed countries - escalating almost up to 80% - than in developing ones, where this rate is about 52%. According to the 6th IPCC Assessment Report, this trend is expected to continue, it’s estimated that over two third of the population will live in cities by 2050 (IPCC, 2022).
On one hand, the increasing urban population is testing cities in many ways in providing affordable housing, viable infrastructure and transport systems, employment, and public and private services for its citizens (The World Bank). Furthermore, the effects of climate change are imposing additional challenges on urban areas. Sustainable cities should consider social, economic and environmental aspects with a holistic approach to provide and sustain a decent level of quality of life for urban citizens. However, endeavours for increasing urban quality of life can easily be hindered by the effects of climate change. As a result of climate change, cities are facing poor air quality, growing temperatures and heat waves.
Along with the urban heat island effect, even higher temperatures are expected in urban areas due to the conversion of the landscape, as urban structures are absorbing and re-emitting heat more than the natural elements. Additionally, extreme weather events such as extreme precipitation and urban flooding, urban water scarcity, landslides, extreme urban wind, and cold spells are projected. The biogeographical breakdown of the observed and projected impacts is summarised in the Figure below.
Figure: Key observed and projected climate change impacts in Europe - Source: EEA, 2020
Urban infrastructure elements are affected by these impacts, influencing the everyday life of millions of urban dwellers in unexpected ways. Effects of climate change may cause disturbances in the provision of services deriving from urban systems, e.g. in the physical infrastructure through transportation, energy and electricity supply, information and communication technology. Services of the social infrastructure systems - associated with appropriate housing, health, education and cultural heritage services – could also be disrupted, while further issues may arise in the urban ecological infrastructure systems responsible for ecosystem services, such as air-filtering, noise pollution reduction, microclimate regulation, recreational and cultural values. These climate-induced effects have further implications, for example, economic loss associated with decreased labour productivity and economic outputs due to higher urban temperatures, health impacts causing higher levels of mortality, risks on human well-being due to water scarcity, costs for urban property damage of extreme weather events, etc (IPCC, 2022).
Cities are severely affected by climate change, however, at the same time, they are a major source of emissions, too – according to the UN’s latest report on sustainable development goals urban areas are responsible for over 70% of the global greenhouse gas emissions. Besides being centres for population and consumption, cities are also the engines of economic growth and innovation and account for more than 80% of the global GDP. Hence, cities are playing a key role in tackling these issues and boosting transition: well-planned and managed urban areas are contributing to sustainable growth, and conscious urban development has the potential to provide an increased quality of life to its citizens (UN DESA, 2022). The functioning of the urban systems is fundamentally influenced by the effects of climate change, cities’ vulnerability is reflected through the type and severity of climate extremes. Enhancement of adaptive capacity and resiliency is essential to reduce vulnerability and tackle the severe impacts of climate change (EEA, 2020). Cities first need to understand their exposure and sensitivity to the impacts when planning for long-term resiliency. Adaptation can be considered as an intervention, and adjustment to the adverse effects of climate change, aiming to reduce cities’ vulnerability. The goal of adaptation is to decrease the extent of and prepare for the unavoidable impacts (Climate Adapt). Appropriate policies for adaptation should be developed, while investments for adaptation measures are also necessary to manage cities’ vulnerabilities. To face the challenges and manage the negative impacts, urban adaptation plans must take into account the local characteristics and expectations, while they also need to recognise the potential of the transformation (World Bank Group, 2011). Local aspects should be taken into consideration when cities are planning for adaptation, there are no one-size-fits-all solutions as local conditions have a strong influence on the feasibility and efficiency of the adaptation measures. Adaptation plans should be developed inclusively reflecting not only on environmental but on social and economic aspects as well (IPCC, 2022).
In the following articles, we will further discuss the impacts of climate change on urban areas in 4 thematic areas: urban temperature, water, air pollution and biodiversity. Besides introducing the expected impacts in detail, we are also aiming to show examples of urban adaptation pathways in all articles, exploring best practices and lessons learnt to increase resiliency and reduce the vulnerability of urban areas.
References – 1.
United Nations – Climate Action: https://www.un.org/en/climatechange/what-is-climate-change
IPCC, 2022: 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, Cambridge, UK and New York, NY, USA, pp. 907–1040, doi:10.1017/9781009325844.008.
UN DESA, 2022: The Sustainable Development Goals Report 2022 - July 2022. New York, USA: UN DESA. © UN DESA. https://unstats.un.org/sdgs/report/2022/
EEA, 2020: European Environment Agency, Kaźmierczak, A., Urban adaptation in Europe: how cities and towns respond to climate change, Publications Office, 2020, https://data.europa.eu/doi/10.2800/324620
World Bank Group, 2011: Guide to climate change adaptation in cities: executive summary (Vol. 2) (English). Washington, D.C. : World Bank Group, 2011, http://documents.worldbank.org/curated/en/691721468320045373/Guide-to-climate-change-adaptation-in-cities-executive-summary
Climate Adapt: Urban Adaptation Support Tool