1. EEA Report No 2/2012ISSN 1725-9177Urban adaptation to climate change in EuropeChallenges and opportunities for citiestogether with supportive national and European policies

2. EEA ReportNo 2/2012Urban adaptation to climate change in EuropeChallenges and opportunities for citiestogether with supportive national and European policies 3. Cover design: EEALayout: EEA/Henriette NilssonCover photo sxc/XpgomesLeft photo RicciardiRight photo sxc/abcd200European Environment AgencyKongens Nytorv 61050 Copenhagen KDenmarkTel.: +45 33 36 71 00Fax: +45 33 36 71 99Web: eea.europa.euEnquiries: eea.europa.eu/enquiriesLegal noticeThe contents of this publication do not necessarily reflect the official opinions of the European Commission or other institutions of the European Union. 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It can be accessed through the Europa server (www.europa.eu).Luxembourg: Office for Official Publications of the European Union, 2012ISBN 978-92-9213-308-5ISSN 1725-9177doi:10.2800/41895 EEA, Copenhagen, 2012Environmental productionThis publication is printed according to high environmental standards.Printed by Rosendahls-Schultz Grafisk Environmental Management Certificate: DS/EN ISO 14001: 2004 Quality Certificate: DS/EN ISO 9001: 2008 EMAS Registration. Licence no. DK 000235 Ecolabelling with the Nordic Swan, licence no. 541 176 FSC Certificate licence code FSC C0688122PaperRePrint FSC Certified 90 gsm.CyclusOffset 250 gsm.Both paper qualities are recycled paper and have obtained the ecolabel Nordic Swan.Printed in DenmarkREG.NO.DK-000244ESPON disclaimer:Texts and maps stemming from research projects under the ESPON programme presented in this report do not necessarily reflect the opinion of the ESPON Monitoring Committee. 4. 3ContentsUrban adaptation to climate change in EuropeContentsAcknowledgements ....................................................................................................5Key messages............................................................................................................. 61 What is this report about and who should read it? ...............................................102 Climate change challenges and response options ................................................132.1 Heat ..............................................................................................................182.1.1 Why are heatwaves an important urban challenge? 182.1.2 What are the potential impacts of heat on Europe's cities? 242.1.3 How can cities adapt to heat stress?..........................................................312.2 Flooding .........................................................................................................352.2.1 What are the challenges for cities regarding flooding? 352.2.2 What are the potential flooding impacts on Europe's cities? ..........................372.2.3 How can cities adapt to flooding?...............................................................482.3 Water scarcity and droughts...............................................................................532.3.1 Why are water scarcity and drought challenges for cities? 532.3.2 What are the potential impacts of water scarcity and droughtson Europe's cities?...................................................................................552.3.3 How can cities adapt to water scarcity and droughts? 593 Planning urban adaptation .................................................................................. 623.1 Capacity to adapt in Europe's cities.....................................................................623.1.1 Awareness: knowledge and equity.............................................................633.1.2 Ability: access to technology and infrastructure 663.1.3 Action: economy, resources and institutions 693.1.4 Summarising the adaptive capacity of cities 723.2 Planning steps to urban adaptation.....................................................................743.2.1 Get started: initiate adaptation, ensure commitment and management...........743.2.2 Assess potential climate change risks and vulnerabilities 753.2.3 Identify a wide range of adaptation options 753.2.4 Assess and prioritise adaptation options.....................................................773.2.5 Implement adaptation actions...................................................................773.2.6 Monitor and evaluate adaptation action......................................................783.3 Success factors ...............................................................................................793.3.1 Raising awareness of climate change and the need to adapt..........................793.3.2 Cutting across different sectors and levels 803.3.3 Utilising the co-benefits of adaptive actions 843.3.4 Dealing with uncertainty and long time frames 863.3.5 Working with nature not against............................................................913.3.6 Securing resources for adaptation .............................................................93 5. Contents4 Urban adaptation to climate change in Europe4 Multi-level governance enabling urban adaptation 954.1 Governing adaptation at different spatial levels ....................................................954.1.1 The local level ........................................................................................964.1.2 The regional level ...................................................................................984.1.3 The national level....................................................................................984.1.4 The European level................................................................................1014.2 Bridging the levels multi-level governance......................................................1064.2.1 The needs and benefits of multi-level governance 1064.2.2 Challenges ...........................................................................................1084.2.3 Success factors ....................................................................................1114.3 Pillars for multi-level governance .....................................................................1124.3.1 Policy coherence through multi-level climate proofing 1124.3.2 Territorial governance ...........................................................................1154.3.3 Developing institutional capacities across levels 1174.3.4 Securing access to funding for adaptation measures 1194.3.5 Multi-level knowledge base.....................................................................122Glossary.................................................................................................................. 125References.............................................................................................................. 128Annex I Key information....................................................................................... 141a) Selection of key literature and studies.......................................................141b) Selection of tools and guidance for adaptation 142Annex II City data.................................................................................................. 143 6. 5AcknowledgementsUrban adaptation to climate change in EuropeAcknowledgementsThis report was written and compiled by: European Environment Agency (EEA):Birgit Georgi with the support of StphaneIsoard, Blaz Kurnik, Valentin Leonard Foltescuunder the guidance of Ronan Uhel andAndr Jol; European Topic Centre Climate ChangeAdaptation (ETC/CCA): Rob Swart, NatashaMarinova, Bert van Hove, Cor Jacobs, JudithKlostermann, Aleksandra Kazmierczak, LassePeltonen, Leena Kopperoinen, Kari Oinonen,Miroslav Havrnek, Maria Joo Cruz; European Topic Centre Spatial Informationand Analysis (ETC/SIA): Mirko Gregor, JaumeFonsEsteve; Ume University: Carina Keskitalo; Aalto University: Sirkku Juhola; Umweltforschungszentrum Leipzig (UFZ):Kerstin Krellenberg; and The Netherlands Environmental AssessmentAgency (PBL): Leendert van Bree.Further contributions were received from:Stefan Greiving, Christian Lindner and JohannesLckenktter (IRPUD, TU Dortmund); LykkeLeonardsen (city of Copenhagen); Ingrid Molander(Botkyrka municipality); Tanja Wolf (WHO Europe);Holger Robrecht and Daniel Morchain (ICLEIEurope); Cdric Peinturier (Ministre de l'cologie,du Dveloppement Durable, des Transports et duLogement, France); Kathy Belpaeme (ICZM Belgium); and Stefaan Gysens.The report team also wishes to thank the manyfurther experts providing support throughout thedevelopment of this report, in particular: CorinneHermant-de Callata, Matthieu Fichter and ZoBuyle-Bodin (European Commission); Alex Harvey(AEA); Johan Bogaert (Flemish government,Belgium); Peter Bosch (TNO); Zoltn Kohn andPti Mrton (VATI); Sandy Taylor (BirminghamCity Council); Michael Klinkenberg (EUROCITIES);Inke Schauser (UBA, Germany); StefanSchneiderbauer (EURAC); Stephanie Broadleyand Michael Chang (TCPA); Anne Holsten, TabeaLissner and Jrgen P. Kropp (PIK); Vincent Vigui(CIRED); Pierre Laconte (Foundation for the UrbanEnvironment); Rita Jacinto, Pedro Garrett and AnaGomes (FFCUL); Tiago Capela Loureno (LisbonUniversity); Christofer strm and Joacim Rocklv(Ume University); Anna Paldy (National Instituteof Environmental Health (NIEH, Hungary);Bertrand Reysset (Ministre de l'cologie, duDveloppement Durable, des Transports et duLogement, France); Buket Akay (Ministry ofEnvironment and Urban, Turkey); Celine Magnier(Ministre de l'cologie, du DveloppementDurable, des Transports et du Logement, France);Else Lobersli (Direktoratet for naturforvaltning,Norway); Francesca Giordano (ISPRA, Italy); PavelStastny (SHMI, Slovakia); Simona Losmanova(CENIA, Czech Republic); Vita Slanke (LVGMC,Latvia); Martin Fssel, Andrus Meiner, Bo Jacobsenand Peter Kristensen (EEA). 7. 6Key messagesUrban adaptation to climate change in EuropeKey messagesClimate change the risk to cities andEuropeClimate change is happening, projected to continueand poses serious challenges for cities. Extremeweather events resulting in hazards such asheatwaves, floods and droughts are expected tohappen more frequently in many parts of Europe.The impacts are stark: flooding can damage orwash away homes, businesses and infrastructure.Jobs and vital services will be lost. Heatwaves cancompromise public health, reduce productivityand constrain the functionality of infrastructure.Water scarcity will place cities in competition forwater with a wide variety of other sectors, includingagriculture, energy generation and tourism.Cities drive Europe's economy and generatesubstantial wealth. If important economic hubs suchas London, Paris or Rotterdam experience climaterelated problems Europe's economy and quality oflife will be under threat.Urbanisation, population ageing andother socio-economic trends interactwith climate changeClimate change is strongly intertwined with othersocio-economic changes. Demographic trends suchas on-going urbanisation and competing demand forwater from the public and sectors such as industryand agriculture leads to regional water scarcity. Anageing population increases the share of peoplevulnerable to heatwaves. Urbanisation also reducesthe area available for natural flood managementor increases the number of homes and businessesactually in flood-prone areas. These socio-economicchanges increase the vulnerability of people,property and ecosystems under current climateconditions as long as no adaptation measures aretaken. Climate change is projected to exacerbatethese problems.Cities face specific climate changechallenges Three quarters of the population of Europe live inurban areas and this is where climate change will bemost apparent in everyday life.While urban areas will generally experience thesame exposures to climate change as surroundingregions, the urban setting can alter this as wellas any potential local impacts. The replacementof natural vegetation with artificial surfaces andbuildings creates unique microclimates alteringtemperature, moisture, wind direction andrainfall patterns. Differences in urban design andmanagement make cities vulnerable in differentways, even those situated in the same geographicregion. Excessive amounts of rain water cannotdrain into the ground where a high share of thecity's area is imperviously sealed and thus generateor worsen floods. A high amount of artificialsurfaces stores heat and cause raised temperaturesin cities compared to the surrounding region.Photo: ESA 8. Key messagesUrban adaptation to climate change in Europe 7 and depend highly on other regions inEurope and beyondCities depend heavily on other cities and regionsto provide them with indispensable services suchas food, water and energy and the infrastructure todeliver them. Ecosystem services from surroundingregions provide fresh air, store or drain flood wateras well as drinking water.Climate change challenges: from riskmanagement to opportunity seizingThe challenges of climate change force drasticchanges in city and regional management soinnovative solutions are required alongsidetraditional measures. Establishing strong spatialplanning which stops placing homes, businesses andinfrastructure into current but also future risk-proneareas or providing more room for rivers can be aneffective and sustainable way to deal with riskscomplementary to building higher dikes. Keepingpublic space and buildings cool by using green roofsor walls and providing more shade, rather than airconditioning, saves energy and can make cities evenmore attractive.Adaptation to climate change offers the opportunityfor developing new jobs and promoting innovationand, at the same time, for implementing theprofound changes needed in managing Europe'scities and regions. This will lead the way towards amore sustainable and resilient future for people, theeconomy and nature.Acting now ensures adaptation in timeand at lower costCities cannot profess being unaware about climatechange. Now is the time to act. Delaying adaptationaction will most probably increase costs at a laterstage or measures will come too late. Infrastructure,such as buildings, roads, railways, energy grids andsewage systems, lasts for decades and is expensiveto replace. Building infrastructure ready for futureclimate conditions and not in risk prone areas(such as floodplains) will result in lower costs andincreased effectiveness.Long-term planning is crucial but has often beenlacking. Some positive examples can, however, befound in other areas such as insurance and pensionplanning. The Norwegian Government PensionFund is one such example as it intends to ensurepensions in the future via a long-term strategy,despite the trend of an ageing population. Therebyit increasingly considers the climate changerelatedrisks of its investments. A similar long-termapproach is needed for infrastructure investments.Maintaining the functioning of urbaninfrastructure requires massiveinvestmentsExisting and future buildings and infrastructureneed huge investments, alongside those forclimateproofing, over the coming decades in orderto keep them functioning and delivering theirservices. It means incorporating climate changeadaptation concerns into building standards andretrofitting activities, such as ensuring that sewagesystems can cope with heavier precipitation,reviewing building designs to better insulate againstheat and adapting the energy and transport systemsto cope with higher temperatures, low wateravailability or flooding.Large financial resources are needed irrespectiveof financial constraints. The Multi-annual FinancialFramework (MFF), in particular the cohesion funds,is a key European Union instrument which supportslocal and regional adaptation. The MMF proposalfor the period 20142020 foresees using a muchhigher share of the budget for climate change (20 %)than in the current period. However, the proposed20 % will support both climate change mitigationand adaptation. Current political discussionsseem very much focused on mitigation rather thanadaptation.Investment goes beyond 'grey'infrastructureAdaptation also relates strongly to using andexpanding green infrastructure such as parks,forests, wetlands, green walls and roofs, whereverfeasible and sustainable. Such infrastructure servesto provide a cooling effect on cities as well asplaying a role in managing floods. Measures whichcombine grey and green infrastructures (1) have thepotential to deliver robust and flexible solutionsover a long period. In addition they can deliver(1) Grey infrastructure: construction measures using engineering services.Green infrastructure: vegetated areas and elements such parks, gardens, wetlands, natural areas, green roofs and walls, trees etc.contributing to the increase of ecosystems resilience and delivery of ecosystem services. 9. Key messages8 Urban adaptation to climate change in Europebenefits such as higher energy efficiency due tolower cooling needs, or attractive areas for nature,wildlife and recreation.'Soft' measures (2) are another option and canoften be implemented at less cost. Such measuresinclude behavioural changes, emergency systemsand the adequate provision of information tovulnerable groups. They can reduce health impactsin the event of heatwaves or flooding. While suchsystems are generally well-established in disasterrisk management programmes they often do notinclude additional risks related to climate change.Investments in capacity building and planningprocesses are required to fully develop the potentialof these soft measures. This would involve: sharing information and building knowledgefor citizens, administrations, politicians andbusiness; enabling and promoting innovation; enabling a broad participation in planningand implementation thereby taking uplocal knowledge and educating people anddecisionmakers; changing long-term planning andimplementation approaches across sectors andgovernmental levels; providing the appropriate institutionalstructures and capacities for mainstreaming andcooperation across sectors and levels.Urban adaptation relies on action beyondcities' bordersEvents outside of cities can have major effectson urban areas. Certain cities, for example, faceflooding due to inappropriate land use and floodmanagement in upstream regions. In water scarceregions cities compete for water with agricultureand other users. Urban adaptation to climate changetherefore requires regional, national and Europeanapproaches.Support from a national and Europeanframework is crucial in assisting cities toadaptCities and regional administrations need toestablish grey and green infrastructures and softlocal measures themselves. National and Europeanpolicy frameworks can enable or speed up localadaptation thus making it more efficient. Supportiveframeworks could comprise of: sufficient and tailored funding of local action; mainstreaming adaptation and local concernsinto different policy areas to ensure coherence; making the legal framework and budgetsclimate-proof; setting an institutional framework to facilitatecooperation between stakeholders across sectorsand levels; providing suitable knowledge and capacities forlocal action.Few European regulations refer to adaptation, buta higher potential exists. One proposal linked to theEuropean Union's structural funds for the period20142020 states that project spending requires theexistence of disaster risk assessments taking intoaccount climate change adaptation as conditionality.It will ensure that expensive and long-lastinginfrastructures are able to cope with future climatechanges. In addition the proposal for the MFF20142020 requests that the budget for climatechange is sourced from different policy sectorsforcing policy mainstreaming and coherence.Europe's future depends on strongand resilient cities towards a joint,multilevel approach to cope with climatechangeEurope needs to build climate change resiliencein its cities. Cities and regions are connected onmultiple levels with cities being key for the economy(2) Soft measures: policies, plans, programmes, procedures. 10. Key messagesUrban adaptation to climate change in Europe 9and wealth generation for Europe. This requiresa joint and comprehensive approach combiningdialogue and partnerships which crosses sectors andgovernmental levels.The development and implementation of theEuropean climate change adaptation strategyfor 2013 offers a unique opportunity to createthis joint approach and reflects efforts citieshave made in recent years to be part of relatedEU policy. Prominent examples, in which theEuropean Commission directly works with citiesand city networks, are the Sustainable Cities andTowns Campaign and the Covenant of Mayorsinitiative. The latter initiative sees more than3 000 municipalities committing themselves toreduce their greenhouse gas emissions. An extensionof this model towards the inclusion of adaptation isin discussion. Moreover, the European Commissionstarted a project in 2011 to support urban adaptationstrategies.This report provides information to facilitate this multi-levelEuropean process and the effective participationof local governments. It complements a range ofother studies and information sources, such as theEuropean Climate Adaptation Information PlatformCLIMATE-ADAPT, the forthcoming EEA reports onclimate change impacts and on adaptation (due inautumn 2012), the handbook on Climate-FriendlyCities (2011), published under the HungarianEU presidency, among others listed later in thereport. 11. 10What is this report about and who should read it?Urban adaptation to climate change in EuropeBox 1.1 Key terms used in this reportUrban areas, cities and towns: Due to a lack of European definitions these terms are used in the reportdepending on the particular context. The indicators in this report generally consider cities with more than100 000 inhabitants. Results and guidance from this report are nevertheless relevant for cities and towns belowthat population threshold. The report uses 'urban areas' as a collective term to fit with the different countryspecific definitions of cities and towns.Adaptation to climate change is the adjustment in natural or human systems (e.g. urban areas) in response toactual or expected climatic stimuli or their effects. It moderates harm or exploits beneficial opportunities of climatechange.Adaptive capacity is the ability of a system, such as urban areas, to adjust to climate change to moderatepotential damages, to take advantage of opportunities or to cope with the consequences.Vulnerability: Many definitions exist according to the context. For example, the United Nations InternationalStrategy for Disaster Reduction (UNISDR, 2009) defines vulnerability as the characteristics and circumstances of acommunity, system or asset that make it susceptible to the damaging effects of a hazard. The IntergovernmentalPanel on Climate Change defines vulnerability to climate change as the degree to which a system is susceptibleto, and unable to cope with, adverse effects of climate change, including climate variability and extremes.Vulnerability is a function of the character, magnitude and rate of climate change and variation to which a systemis exposed, its sensitivity, and its adaptive capacity (CoR, 2011a; IPCC, 2007). While being aware of the differentdefinitions and concepts of vulnerability, we do not use a specific definition or concept stringently in this report butrather use the term in a more generic way.Mitigation of climate change is an anthropogenic intervention to reduce the anthropogenic forcing of theclimate system. It includes strategies to reduce greenhouse gas sources and emissions and enhancing greenhousegas sinks.More terms can be found in the glossary at the end of this report.1 What is this report about and whoshould read it?The need for an urban focus on climatechange adaptation in EuropeClimate change leading to higher temperatures,changing precipitation patterns and sea level rise,is a reality in Europe. Climate change mitigationmeasures will limit the magnitude and rate ofrelated events in the future, but they will not preventthem. Pro-active adaptation to climate change istherefore imperative (EEA, 2010a).Around three quarters of Europe's population livein urban areas (EEA, 2006; EEA, 2010b). Urbanareas are the places in Europe where most peoplewill be vulnerable to the effects of climate change.At the same time cities are Europe's economiccentres. Innovation and major economic assets areconcentrated here (EC, 2009a). Urban areas adaptedto climate change are key for Europe's future. Thelarge and growing size of the urban population,cities' economic assets and the complexity of citysystems to provide and manage energy, water,waste, food and other services make urban areashighly vulnerable to both current climate variabilityand future climate change. Urban areas needfocused attention across Europe and a specificapproach.While urban adaptation to climate change at a firstglance may seem to be purely a local governanceissue, the strong connections between Europeancities and their surrounding regions, or countries,warrant a broader perspective. 12. What is this report about and who should read it?Urban adaptation to climate change in Europe 11Figure 1.1 Framework of the reportClimate changeexposure Temperature Precipitation Sea levelSensitivity of cities to Heat Flooding Water scarcityPotential climatechange impactson citiesPossible adaptationmeasures reducingthe sensitivityChapter 2 Climate change challenges Chapter 3 Planning urban adaptationChapter 4 Multi-level governanceAdaptive capacity ofcities to cope with theimpacts and reducethe vulnerabilityPlanningurbanadaptationandsuccessfactorsMulti-level governance action to facilitateand implement adaptationFocus and target audience of this reportFrom a European perspective, this report informsabout the key challenges that climate change posesto cities and the need for urban adaptation. Itpositions the urban challenges in the larger policyframeworks provided by regional, national andEuropean institutions and it gives a summaryoverview of opportunities for solutions.As such, the report addresses stakeholders involvedin urban development at local and city level as wellas at regional, national and European level. It aimsto support policy development and decision-makingacross all these levels. This report takes key policyquestions for specific climate-related problems,which are common for groups of cities, as thestarting point of the assessment. It presents: the most important potential impacts of climatechange on cities in Europe: it characterisescities interms of their vulnerability or adaptivecapacity to climate change due to factors such asgeographic position, urban design, size, wealthor governance system; a range of adaptation responses for differentspatial levels; the challenges and opportunities for multi-levelgovernance in the relevant policy frameworks.Because of its question-guided approach, thereport does not provide a comprehensive scientificassessment of all possible potential climatechange impacts and associated adaptation optionsacross all European urban areas. It synthesisesexisting data and research results around selectedkey climate challenges for cities and focuses atproviding the information needed by Europeanand national and to some extent by regional andlocal decision-makers to decrease the vulnerabilityof cities across Europe in a multi-level policyframework (Figure 1.1). 13. What is this report about and who should read it?12 Urban adaptation to climate change in EuropeBox 1.2 Examples of what stakeholders can expect from the reportStakeholders in all governments, communities and networks, theprivate sector and research: support towards a better understanding of their own position and rolein the overall European context in enabling urban adaptation to climatechange, such as developing coherent policies towards adaptation,implementing effective adaptation or closing research and informationgaps; an overview of the differences and similarities between cities and regionsencouraging mutual learning; a cross-sectoral and multi-level perspective that encourages'outofthebox' thinking, challenges creativity and reveals the manycrossbenefits of good adaptation.European and national level stakeholders: information to create awareness about urban vulnerability to climatechange and the awareness that several types of impacts as well assolutions depend on action at national and European level; information on the opportunities to mainstream urban adaptation intothe different European and national policy areas in order to identifypotentially adverse impacts and opportunities, overcome barriers and thus enable effective local adaptation; information on European patterns of urban vulnerability as input into the development of more targetedfunding programmes, such as the EU's structural funds and for research.City and regional governments: in a European context, provide information to raise awareness of future climate change challenges for urbanareas and their related regions and potential options for adaptation action; the ability to start comparing one's vulnerability and response options with other cities, exploring the reasonsbehind and ways to reduce this vulnerability; an understandable methodological framework, facilitating the transition between awareness of cities' climatechallenges and the development of targeted adaptation actions; a suggestion about the potential and benefits of active participation of local governments in a multi-levelgovernance approach and in the development and implementation of the 2013 EU adaptation strategy andnational strategies; the report does not provide guidance for detailed local adaptation planning due to the high number anddiversity of local situations and the report's focus on the European perspective of the urban challenges.Building on earlier efforts in support ofthe 2013 EU adaptation strategyThis report builds on a number of other reportssuch as the Committee of the Regions' studyAdaptation to Climate Change (CoR, 2011a), thehandbook Climate-friendly Cities (VTI, 2011), thescoping study Urban Regions Vulnerabilities,Vulnerability Assessments by Indicators andAdaptation Options for Climate Change Impacts(Schauser et al., 2010), a variety of local studiesand initiatives such as the Resilient Citiesconferences. It provides a European overviewof the challenges and opportunities of urbanadaptation to climate change and links them withthese other initiatives that provide more detailedinformation on local climate change impacts, andgood practice guidance. As such it facilitates thedebate on European and national support forurban adaptation, feeds into the European ClimateAdaptation Platform ClimateADAPT, and supportsan effective participation of local governments inthe development and implementation of the 2013EU adaptation strategy (EC, 2009b) by providingsupportive information. 14. 13Climate change challenges and response optionsUrban adaptation to climate change in Europe2 Climate change challenges andresponse optionsWeather and climate strongly influence human lifein cities. While exposure to weather and climate isimportant in the present climate, climate changemay exacerbate or ameliorate any potential exposureand subsequent impacts.Cities and towns, just as the rest of Europe, willbe affected by the impacts of climate change.Current observations of change are well in linewith projections of the average climate change(Van Engelen et al., 2008), which suggest: an increase of the annual mean temperatureacross Europe between 2 and 5 C by the end ofthis century, relative to the present-day climate; a change of precipitation patterns with driersummer conditions in the Mediterranean areaand wetter winter conditions in NorthernEurope; a rise of the sea level (Christensen et al., 2007;Van der Linden and Mitchell, 2009; Greivinget al., 2011).Apart from the changes in average climate, thenumber, intensity and duration of heatwaves,extreme precipitation events and drought isexpected to increase (Barriopedro et al., 2011; Giorgiet al., 2011; Hoerling et al., 2012).Climate change and its impacts will not appearuniformly in Europe. Different regions willexperience varying intensities of change. Map 2.1identifies five European regions facing similarclimate change issues. It is based on a clusteranalysis of eight climate change variables whichwere calculated on the basis of a comparison of19611990 and 20712100 climate projectionsfrom the IPCC SRES scenario A1B (3) scenario(Greiving et al., 2011). The map illustrates that(3) SRES refers to the scenarios described in the IPCC Special Report on Emissions Scenarios (IPCC, 2000). The SRES scenarios aregrouped into four scenario families (A1, A2, B1 and B2) that explore alternative development pathways (see further explanation inthe glossary).different regions can have similar climate changecharacteristics, and that in one EU MemberState, its regions can have very different climatecharacteristics. Those working on climate changeadaptation in some regions may find regions withsimilar climate challenges in other countries ratherthan within their own.While urban areas will generally experience thesame exposures to climate as their surroundingregion, the urban setting its form andsocioeconomic activity can alter exposures aswell as impacts at the local scale. Built-up areas inthe cities create unique microclimates due to thereplacement of natural vegetation with artificialsurfaces. This affects air temperature, winddirection and precipitation patterns, amongst others.Climate change will affect all of these components,exacerbating some of them and lessening others.Beyond direct climate change impacts, such ashealth problems due to heat or damages to buildingsand infrastructure due to flooding, the indirectimpacts on cities can be much broader. In a worldwhere every city and every region is connectedin a multitude of ways to other cities and regions,the failure of one strand of this complex webwill create a knock-on effect. Floods can destroyhomes, business sites and infrastructure as well ascontributing indirectly to loss of jobs and incomesources, for example. People and businesses will becut off from vital services such as energy, transportand clean water. Heatwaves can compromise publichealth, reduce the ability to work and result inlower productivity thus shortening or delayingthe delivery of products and services to clients inthe city and elsewhere. They can reduce the useof public spaces and thus constrain social life.High temperatures can put infrastructure at risk deformed roads and rail tracks can hamper thesupply of goods and commuters or, in particular in 15. Climate change challenges and response options14 Urban adaptation to climate change in EuropeCluster/stimuli Northern-centralEuropeNorthernwesternEuropeNorthernEuropeSoutherncentralEuropeMediterraneanEuropeChange in annual mean temperature + + ++ ++ ++Decrease in number of frost days Change in annual mean number of summerdays+ + 0 ++ ++Relative change in annual mean precipitationin winter months+ + ++ 0 Relative change in annual mean precipitationin summer months 0 Change in annual mean number of days withheavy rainfall0 + + 0 Relative change in annual mean evaporation + 0 + 0 Change in annual mean number of days withsnow cover CDSC 0 0 0Map 2.1 European regions clustered according to projected climate changesNote: Key: ++ Strong increase; + Increase;0 Insignificant stimulus for the characterisation of the cluster; Decrease; Strong decrease.The map is based on a cluster analysis and represents aggregated data. Therefore in some areas a specific climate factormight point in a different or even opposite direction than indicated in the cluster.Source: Greiving et al., 2011; ESPON, 2013.EUROPEAN UNION Origin of data: own calculation based on Lautenschlager et al. 2009Part-financed by the european Regional Development fundINVESTING IN YOUR FUTUREEuropean climate change regionsThis map does notnecessarily reflect theopinion of the ESPONMonitoring CommitteeCanariasGuadeloupe Martinique RunionGuyaneMadeiraAcores 16. Climate change challenges and response optionsUrban adaptation to climate change in Europe 15Box 2.1 Reducing cities' dependency onexternal servicesCities are highly dependent on vulnerable externalservices but can strategically plan to ensure serviceprovision under future climate conditions.Firstly, they can take action to reduce supply systemvulnerability e.g. by locating power and communicationlines underground or creating multiple supply lines.This approach involves measures going beyond cityboundaries requiring cooperation, coordination,lobbying and policy agreements on a regional, nationaland sometimes European level (see Section 3.2)(OECD, 2010).Secondly, cities can take measures to become moreindependent of external services and can prepare forsomething as extreme as a system failure (CAP, 2007).This requires action at all levels. It can include measuresto reduce energy demand or to generate energy locally, e.g. building of passive houses (ultra-low energy houses),solar panels on roofs and promotion of district cooling and heating systems. Municipalities can relocate vulnerableurban transport infrastructure and make it climate-proof, improve water use efficiency, reduce losses from thewater supply systems and build local water storage facilities and other back-up systems (CAP, 2007). Greeninfrastructure approaches can consider the capture and use of rainwater as well as recharging groundwaterthrough rain and grey water infiltration. Interconnection between regional water and energy supply systems canserve as a back-up, reducing the likelihood of a failure. Measures towards greater independence may well beconsidered on a metropolitan or regional scale instead of at a uniquely city level (VTI, 2011; CoR, 2011a; CAP,2007; Greater London Authority, 2010).combination with droughts, power stations mightnot get sufficient cooling water and thus fail todeliver energy. Potential drops in the productionof food, goods and services outside the cities willconstrain services in the cities. Water scarcity placescities into a water competition with other sectorssuch as agriculture and tourism and poses highereconomic pressures on the city or individuals toaccess sufficient water thereby challenging socialequity. These indirect impacts challenge in a muchbroader way the economy and quality of life incities and in Europe as a whole (response options inBox 2.1).While these indirect impacts are extremelyimportant their analysis is complex and requiresdifferent data as well as analysis above and beyondthat usually used for climate change vulnerabilityassessments. This goes beyond the scope of thisreport which concentrates, as an initial step, on moredirect climate change impacts and vulnerabilities incities. Sections 2.12.3 focus on a selection of climatechallenges which are of particular relevance forurban areas: heat; flooding; water scarcity and droughts.Although a large number of subjects with an urbancomponent, such as storms, forest fires, landslidesand erosion, can be defined, this selection isintended to illustrate why and how the specificurban context comes into play when consideringclimate change issues in cities and towns. Theassessment of these direct impacts can then serveas the input to future broader assessments of thesecondary and tertiary effects on the economy, socialequity and quality of life in cities and in Europe as awhole.In this report, the assessment builds on Europeanclimate change projections and relates them toseveral key indicators of cities' sensitivity relatedto urban design and socio-economic structure.The assessment follows, in general, the scheme inFigure 2.1. However, quantitative, Europe-widedata for cities are scarce and do not allow for afully-fledged assessment. The report considers upto 576 cities with more than 100 000 inhabitantsand in a few cases below that population number.For these larger cities, data were available in theurban audit database (Eurostat, 2012) although thisis not complete for every indicator. The analysisof potential climate change impacts is thereforerather descriptive as it uses additional qualitativeinformation and illustrative examples.Photo: Ian Britton 17. Climate change challenges and response options16 Urban adaptation to climate change in EuropeClimate changeexposure Temperature Precipitation Sea levelSensitivity of cities to Heat Flooding Water scarcityPotential climatechange impactson citiesPossible adaptationmeasures reducingthe sensitivityChapter 2 Climate change challenges Chapter 3 Planning urban adaptationChapter 4 Multi-level governanceAdaptive capacity ofcities to cope with theimpacts and reducethe vulnerabilityPlanningurbanadaptationandsuccessfactorsMulti-level governance action to facilitateand implement adaptationFigure 2.1 Placing Chapter 2 within the framework of the reportBox 2.2 Classification of adaptation options as applied in the reportAdaptation options can be categorised in different ways. This report builds on the classifications used in the EU'sWhite Paper on adapting to climate change (EC, 2009b): 'Grey' infrastructure approaches correspond to 'physical interventions or construction measures and usingengineering services to make buildings and infrastructure essential for the social and economic well-being ofsociety more capable of withstanding extreme events.' 'Green' infrastructure approaches contribute to the increase of ecosystems resilience and can haltbiodiversity loss, degradation of ecosystem and restore water cycles. At the same time, green infrastructureuses the functions and services provided by the ecosystems to achieve a more cost effective and sometimesmore feasible adaptation solution than grey infrastructure. 'Soft' approaches correspond to 'design and application of policies and procedures and employing, interalia, land-use controls, information dissemination and economic incentives to reduce vulnerability, encourageadaptive behaviour or avoid maladaptations. They require careful management of the underlying humansystems'. Some of these measures can facilitate the implementation of grey or green measures (e.g. funding,integration of climate change into regulations). Many types of soft measures are particularly relevant whenuncertainties about the expected changes are large, since they enhance the adaptive capacity (UNECE, 2009).Measures in general can be of a preventive character and improve resilience yet they can also offer preparativesupport when dealing with the anticipated effects of climate change and extreme events. They can also provideresponses to direct effects or aim to assist in the recovery of economic, societal and natural systems following anextreme event (UNECE, 2009). 18. Climate change challenges and response optionsUrban adaptation to climate change in Europe 17Further reading EEA, JRC and WHO, 2008, Impacts of Europe's changing climate: 2008 indicator-based assessment,EEA Report No 4/2008, European Environment Agency (http://www.eea.europa.eu/publications/eea_report_2008_4). IPCC, 2007, Climate change 2007: Synthesis report. Contribution of Working Groups I, II and III to theFourth Assessment Report of the Intergovernmental Panel on Climate Change, Cambridge University Press,Cambridge, United Kingdom (http://www.ipcc.ch/pdf/assessment-report/ar4/syr/ar4_syr.pdf).Finally, Chapter 2 lists a range of possible adaptationmeasures per climate challenge. The optionspresented do not pretend to be comprehensivesince the most appropriate solutions are tailor-madeto account for local urban characteristics, whichare very different for different regions in Europe.Chapter 3 provides, in addition, an overviewof generic ways to increase resilience to climatechange.There are a number of ways to adapt to climatevariability and change and various methodsto then classify them. This report follows theEU's White Paper 'Adapting to climate change'classification, distinguishing between 'grey' and'green' infrastructure and 'soft' approaches (seeBox 2.2). Other classifications relate to the optionsfor response in terms of their timing in view ofprevention, preparation and response choices(EC, 2009b; UNECE, 2009). 19. Climate change challenges and response options18 Urban adaptation to climate change in EuropeKey messages In Europe, of those natural disasters occurring in recent decades, heatwaves have caused the most humanfatalities. During the summer of 2003 the heatwave in Central and Western Europe was estimated to havecaused up to 70 000 excess deaths over a four-month period. It is highly likely that the length, frequency and/or intensity of heatwaves will increase. Present day design of many cities with few green urban areas but many artificial surfaces aggravates theimpact of heatwaves within cities, in particular by increasing night-time temperatures. Based on the indicators used in this chapter, there are larger numbers of sensitive cities across Europe, withthe exception of northern Europe and parts of eastern Europe. A large build-up of heat in Southern andEastern Europe and its northward shift in the future will have a huge impact on many cities in Europe. Local city characteristics tend to be highly important in terms of sensitivity to heat. The results suggest thatcities designed in such a way that makes them susceptible to heat are not unique to one particular region.There are sensitive cities in high heat regions which need specific consideration but there are also northernEuropean cities which need consideration. City governments have a range of options at their disposal to be better prepared for future heat conditions,including 'grey', 'green' and variety of 'soft' solutions.Box 2.3 Recent major heatwaves in EuropeThe summer 2003 European heatwave caused up to70 000 excess deaths over four months in Central andWestern Europe (Brcker, 2005; Robine et al., 2008;Sardon, 2007). It struck the elderly disproportionatelyhard: the daily mortality rate of the population over65 years old rose by 36 % in Barcelona, 44 % in Londonand 105 % in Paris. Moreover the impact of heat on thedaily mortality rate clearly increased with age (D'Ippolitiet al., 2010). Note that on specific days and for specificage and gender groups the daily mortality rates may risefar beyond these numbers, with excess mortality ratesup to a factor of three and more (see, e.g. Hmon andJougla, 2004).The intense heatwave in Eastern Europe in theyear 2010 led to an estimated death toll of 55 000(Barriopedro et al., 2011).The EuroHeat project analysed the cities of Athens, Barcelona, Budapest, London, Milan, Munich, Paris, Romeand Valencia. The study estimated that during the consecutive summer months of June to August for the period19902004 mortality rates increased when heatwaves occurred. The increase ranged from 7.6 % to 33.6 %depending on the city in question (D'Ippoliti et al., 2010).(4) There is no generally accepted definition of 'heatwave' with the definition differing per country (WHO, 2004) and even per sector. Ingeneral, a heatwave is a prolonged period of unusually hot weather. 'Unusually hot' obviously depends on the background climate.2.1 Heat2.1.1 Why are heatwaves an important urbanchallenge?In Europe, of those natural disasters occurringin recent decades, heatwaves (4) have caused themost human fatalities (EEA, 2010c). The Europeanheatwave during the summer of 2003 was estimatedto have caused up to 70 000 excess deaths during afour month period in Central and Western Europe(Brcker, 2005; Robine et al., 2008; Sardon, 2007)(see also Box 2.3). This heatwave demonstrated thatthis issue was not unique to southern Europe. CitiesPhoto: iStockphoto 20. Climate change challenges and response optionsUrban adaptation to climate change in Europe 19Box 2.4 Heatwaves a problem for the southWhile preparing their local adaptation strategy the townof Cascais in Portugal studied the potential adversehealth impacts of climate change in the municipality.The results show that an increase of 1 C above thethreshold of 30 C led to a 4.7 % increase of the risk ofmortality. Since all future climate scenarios for Cascaisindicate significant increases in days with temperaturesabove this threshold, the risk of dying from heat stresswill rise.Cascais is now implementing a number of adaptationmeasures. One project, called the 'Local GreenStructure', restructures and links several ecologicalcorridors, such as gardens, valleys and streams, bothin natural and urban areas. This structure shall, at thesame time, protect and restore local biodiversity andreduce vulnerability to floods.A special contingency plan uses socio-demographicvariables to map sensitive groups in the municipality,e.g. elderly people, people with chronic diseases,children. In the event of an alert for a heatwave, localhospitals, health centres and civil protection services willbe called out to support those identified as vulnerable.Source: Casimiro et al., 2010; http://www.siam.fc.ul.pt/PECAC. as well as the northOne would be surprised to learn that heatwaves are considered to be one of the biggest threats to public healthconnected to climate change in Sweden.Researchers at the University of Ume in Sweden have found that death rates rose significantly when the averagetemperature stayed over 2223 C for more than two consecutive days.During July 2010, the mean temperature stayed above 22 C for nearly two weeks in most parts of Swedenincluding in Botkyrka in the Stockholm region. Botkyrka was the only Swedish municipality that was preparedfor heatwaves. Researchers, in conjunction with the municipality, had been collaborating on mapping risks andthe vulnerable. With the help of Geographic Information Systems (GIS) and using national registers and localinformation, levels of risk and preparedness emerged during the project period of 20082010. One fourth of thepopulation was deemed to be vulnerable.In March 2010, a workshop on heatwaves and health was arranged for all middle management working in thesocial care department of Botkyrka and those involved with responding to emergencies and representatives fromcentral office. The social care department then distributed advice and instructions on dealing with heatwaves forall relevant municipal services. As a result people that were assisted by the municipal care sector were betterprepared in Botkyrka during the 2010 heatwave.Advice is now published on the municipality's homepage and was personally communicated to people in carehomes (see Box 2.8). Nevertheless, awareness still needs to be raised for the general public. Furthermore, a mapmarking public 'cool spaces' is in production.The project concluded that municipalities have to be more aware and take precautions within the administrationas a whole. City planning, risk management, the care sector and city leaders will have to take the threat ofheatwaves into consideration on a more active basis in the future.Source: Ingrid Molander, Botkyrka municipality, Christofer strm and Joacim Rocklv, Ume University, personal communication,2011; http://www.botkyrka.se/Nyheter/Sidor/Vrmeblja-.aspx.Photo: Stelosaworse affected were those where heatwave episodeshad traditionally been rare or where temperaturesstrongly exceeded the usual seasonal conditions(D'Ippoliti et al., 2010) such as in Belgium, Germany,the Netherlands, Switzerland and, the UnitedKingdom. The example of Botkyrka, Sweden showsthe combination of a low heatwave threshold fornorthern European countries and how the sensitivitycan be reduced by raising awareness, changingbehaviour and appropriate building design(Box 2.4). 21. Climate change challenges and response options20 Urban adaptation to climate change in Europe(5) Whether or not citizens feel comfortable with the urban micro climate they encounter depends on a complex interaction betweenphysical, physiological, behavioural and psychological factors. Apart from the physical and biological factors perception plays animportant role.Athens 32.7 Ljubljana 21.5 Rome 30.3Barcelona 22.4 London 23.9 Stockholm 21.7Budapest 22.8 Milan 31.8 Turin 27.0Dublin 23.9 Paris 24.1 Valencia 28.2Helsinki 23.6 Prague 22.0 Zurich 21.8Note: An increase in mortality rates was reported when temperatures passed this threshold.City-specific estimates of the relevant parameters were obtained from the period 19902004.Source: Baccini et al., 2008.Table 2.1 City specific temperature threshold (C) index describing the relative discomfort dueto combined heat and high humidityHeatwaves and human healthAn increase in the mortality rate is the mostdramatic impact of heatwaves. Exposure to hotweather can also have other negative impacts onhuman health and well-being.Humans depend on the body's capability tomaintain internal temperature at around 37 C. Theprinciple mechanisms to prevent thermal stressare sweat production, increased cardiac outputand redirection of blood flow to the skin (Hajatet al., 2010). Diminished or delayed physiologicalresponses cause people to be extra sensitive to heatexposure. In particular the elderly, young childrenand those using certain medication are sensitive toheat (Kovats and Shakoor Hajat, 2008) as well aspregnant women.In addition, socio-economic and behavioural factorsenhance sensitivity to heat at the communitylevel. Such factors include gender, social isolation,homelessness, lack of mobility, alcohol use, beingdressed inappropriately, intensive outdoor labourand low income or poverty (Kovats and Hajat, 2008;Hajat et al., 2010; Wilhelmi and Hayden, 2010). Inmany cases, in particular in cities, a number of thesefactors act together. For example in low incomegroups people are more likely to be obese and haveinadequate housing (Kovats and Hajat, 2008; Reidet al., 2009). Elderly people are more likely to besocially isolated, to be less mobile and to sufferfrom chronic disease while also having reducedphysiological responses (Luber and McGeehin, 2008;Martens, 1998; Hajat and Kosatky, 2009).People can, nevertheless, acclimatise to heat to acertain extent. Initial physiological acclimatisation isfairly fast and may occur after several days throughincreased sweating (Martens, 1998; Haines et al.,2006). However, even with more comprehensiveand long term acclimatisation and change of habits,temperature and humidity above certain local andindividual thresholds can place stress on peoplewith health implications.Since geographic location and average temperatureare closely linked, mortality related to heat seems tobe linked with geographic position (Keatinge et al.,2000; Baccini et al., 2008; Martiello and Giacchi,2010). The comfort temperature (5) or heat thresholdsat which the mortality rate is minimal, is associatedwith the average temperature that communitiesexperience (Martens, 1998) and is indeed higher inareas closer to the equator (Baccini et al., 2008; Hajatand Kosatky, 2009). This is also generally shownin Table 2.1, where the comfort temperatures of anumber of European cities are compared. However,there is no clear relation between geographiclocation and the rate of increase of mortality oncethe comfort temperature is exceeded. Reasons couldinclude the proportion of elderly residents, thegross domestic product, population density andbehaviour.High temperatures during the night play a decisiverole for the serious health effects during heatwaves.Hot days without the relief of cool nights andsubsequent exhaustion increase the effects (Grizeet al., 2005; Kovats and Hajat, 2008; Dousset et al.,2011). 22. Climate change challenges and response optionsUrban adaptation to climate change in Europe 21Meteorological factors Morphological factors Human factors aggravating heat impactsRadiationTemperatureWind speedGeographical location and topographyVegetation and water areasHigh building massPresence of impervious coverStructure that hinders ventilationUrbanisation with a high share of built-up land andimpervious areasPopulation densityLittle shadowingInsufficient building insulationAdditional heat production due to production processes,transport, heating etc.Table 2.2 Factors determining the strength of the urban heat island effect (UHI) and its impactsBeyond the direct health impacts of thermalstress, other potential effects of heat on health,socioeconomic and environmental impacts include: impacts on well-being (psychological impacts,increased violence and social unrest); impacts on water resources (water pollutioncaused by a combination of low water flow andheat; water shortages; changes in patterns ofvector-borne diseases); impacts on economy and infrastructure (reducedproductivity of workers in conditions ofextreme heat; increased hospital admissions andpressure on care services in summer; increasedfailure of transport networks in summer, butless in winter; increased demand for cooling insummer, but decreased demand for heating inwinter; Failure of power supplies (Wilby, 2008;Schauser et al., 2010; EEA et al., 2008; Oke, 1982); changes in patterns of vector-borne diseases.The Urban Heat Island effectThe impact of heatwaves is particularly strong incities and towns. The so-called 'Urban Heat Island'(UHI) describes the increased temperature of theurban air compared to its rural surroundings. Thetemperature difference can be up to 10 C or more(Oke, 1982). The difference is particularly stark atnight. Even relatively small towns can experience aconsiderable UHI (Steeneveld et al., 2011). Factorsdetermining the strength of the UHI are summarisedin Table 2.2.Urbanisation and human activities essentiallyalter the balance between the energy from the sunabsorbed by the surface, then stored in the buildingmass and later released to the surrounding air. Mostnotably, the cooling effect of vegetated surfacesis replaced by the storage of heat in surfaces suchas concrete, asphalt and stone. The effect of thisalteration is clearly visible in Map 2.2, which revealsmuch higher surface temperatures in areas ofBudapest with a higher degree of soil sealing.Thus, the intensity of heatwaves in towns and citiesis influenced by the urban fabric and design (Oke,1982; Arnfield, 2003; Wilhelmi et al., 2004). Sincethe urban fabric shows large amounts of variationthe intensity of the UHI would reflect this. This cancause spatial variations of heat effects within citiesas well as between cities (Smargiassi et al., 2009;Heusinkveld et al., 2010; Dousset et al., 2011; Knightet al., 2010). The hottest parts in cities and townsare generally those with numerous tall buildings,without green spaces and including areas generatinglarge amounts of anthropogenic heat (EEA et al.,2008).Wind plays a special role in the interaction betweenthe urban fabric and weather, not only becausereduced wind speed generally increases UHIstrength (Oke, 1987; Wilby, 2008), but also becauseso-called 'wind-paths' may offer opportunitiesto ventilate cities. Streets, oriented in the samedirection as wind flow, tend to channel the air into 23. Climate change challenges and response options22 Urban adaptation to climate change in Europejets called urban wind canyons. During calm andclear nights associated with a strong UHI level, airrises over the city and induces a horizontal flow ofair from the rural environment into the city (Oke,1987; Kuttler, 2008) (see the Stuttgart example inBox 2.5).Map 2.2 Degree of soil sealing (left) and observed surface temperature (right) in Budapest,Hungary0 30 50 80 100Degree of soil sealing (%)Degree of soil sealing (impermeability) of Budapest 15 16 19 22 25 28 31 34 35 36 37 40 4345Temperature (C)Surface temperature of Budapest, 1 August 2005, 9:30 CET0 5 10 KmNote: The lower surface temperature in areas with urban green and water can clearly be seen. Although surface temperature doesnot equal air temperature, surface temperature is often used to detect the UHI, in the form of the so-called surface UHI.Source: EEA, 2010b; Ongjerth et al., 2007; Gbor et al., 2008.Climate change essentially increases the number ofhot days by a similar amount for both urban andrural situations. However, the number of additionalhot nights is larger in cities than in the countryside.Urban areas store more heat during the day thangreener rural areas and release this heat during thenight. 24. Climate change challenges and response optionsUrban adaptation to climate change in Europe 23Box 2.5 Stuttgart managing urban heat island effectsStuttgart's climate planning strategy is an excellent example of urban heat island management. The city ofStuttgart has been designed to not only respect and protect nature, but to exploit how natural wind patterns anddense vegetation can actively help the city to reduce its problems of overheating and air pollution. At night cool airsweeps down from the surrounding hills and runs through a series of 'ventilation-corridors' which have been keptopen as wide, tree-flanked arteries within the city's street infrastructure.Map 2.3 Climate analysis map for the Stuttgart region, also showing so-called ventilationpaths along with other climate related featuresAreas of cold airAreas of production of cold airAreas of collection of cold airBarrier for the flow of cold airAir exchangeMountain/valley wind systemDownhill flow of cool airClean air ventilation corridorPolluted air ventilation corridorSource: Baumller and Verband Region Stuttgart, 2008; Klimaatlas Region Stuttgart; http://www.stadtklima-stuttgart.de/index.php?klima_klimaatlas_region. 25. Climate change challenges and response options24 Urban adaptation to climate change in Europe2.1.2 What are the potential impacts of heat onEurope's cities?Future exposure to heat in European citiesEurope has seen an increase in temperature of 0.3 Cper decade since the 1970s and has experiencedan increase in the number of heat incidents in thepast two decades (Klein Tank and Knnen, 2003).At least two summers in the last decade (2003 and2010) have in all likelihood been the warmest of thelast 500 years in Europe (Barriopedro et al., 2011).Climate change scenarios indicate that there willbe an increasing probability of mega heatwaves(prolonged heatwaves over large areas such as thoseobserved in 2003 and 2010) over highly populatedareas of Europe (Barriopedro et al., 2011). It is verylikely that the length, frequency and/or intensity ofwarm spells, or heatwaves, will increase (Fischerand Schr, 2010; IPCC, 2012).Southern Europe in particular is affected by hotsummer days and tropical nights. Projections inMap 2.4 indicate an increase in the number ofcombined tropical nights and hot days in the futureand also a clear northward expansion of the affectedregions (Fischer and Schr, 2010). Temperatureextremes as well as the duration of heatwavesIncrease in the number of combined tropical nights (minimum temperature exceeding 20 C) and hot days (maximumtemperature exceeding 35 C) under present and future climate conditions2 6 10 14 18 22 26 30 34 38 42 46 50ENS MEAN 19611990 ENS MEAN 20212050 ENS MEAN 20712100CMap 2.4 Increase in the number of combined tropical nights (minimum temperature exceeding20 C) and hot days (maximum temperature exceeding 35 C) under present and futureclimate conditionsSource: Fischer and Schr, 2010.are expected to increase further (Sterl et al., 2008;Barriopedro et al., 2011). The exceptional summerof 2003 may be viewed as normal in the mid-21stcentury (Fischer and Schr, 2010; Schr et al., 2004).Cities' sensitivity to heatThe scenario above notes the increase in regionalheatwave days. However, it does not take intoaccount the impact on the urban fabric and theresulting exacerbated heatwave effect in cities. Thescenario underestimates in particular the number oftropical nights in cities, which are decisive for healthimpacts.Map 2.5 provides a first assessment of the possiblefuture heat impacts on European cities. Here thescenario map for the period 20712100 is overlaidwith population density and the percentage shareof green and blue areas in major European cities.Both provide a proxy to the urban heat island effect.Population density is associated with variablessuch as building density, green/blue area share andanthropogenic heat production (Steeneveld et al.,2011). The influence of green and blue urban areashas been explained in Section 2.1.1. 26. Climate change challenges and response optionsUrban adaptation to climate change in Europe 25The map indicates a large number of cities withlarge UHI potential in the north-west due tolow shares of green and blue urban areas andin particular south-eastern of Europe where, inaddition, population densities are higher. In thewestern part of the Mediterranean area, the UHIpotential seems to be quite variable, with a mix ofcities with both strong and weak UHI potential.Comparing expected heat exposure changes withthe UHI potential reveals that a large share of citiesin eastern and southern Europe will experiencerelatively strong increases in heat load in the future.If the heatwave intensity expands more to thenorthwest than expected from the results shown40 50 603030202010100-30 -20 -10 06060505040400 500 1000 1500 kmHeat waves both a lowshare of green and blueurban areas and highpopulation densitiescontribute potentially tothe urban heat islandin cities 2020293039 40Green/blue areas per city(UMZ), 2006 (%)Population density per city(UMZ), 2004 (inh./km2) 3 0003 0004 0004 0005 0005 00010 000 10 000Number of combined tropicalnights ( 20 C) and hot days( 35 C), 207021002 10 18 26 34 38 42 50Map 2.5 Heatwaves both a low share of green and blue urban areas and high populationdensities can contribute to the urban heat island effect in citiesNote: The background map presents the projection for the period 2071-2100. Values for the earlier periods are presented inMap 2.4.City data for Bulgaria and Ireland are from 2001; the concept of city is defined uniquely by the urban land-use areas withinits administrative boundary.Source: Eurostat, Urban Audit database, 2004; EEA Urban Atlas, 2006.here (see other indicators used by Fischer and Schr,2010), cities in the Benelux countries and the UnitedKingdom would also be more affected.These results suggest that those cities physicallysensitive to heat impacts do not cluster in oneregion only. There are indeed highly sensitive citiesin regions with an expected high heat load whichneed specific consideration but northern cities arealso sensitive and deserve consideration. At thesame time some cities in southern Europe seemto be less physically sensitive than others. Localcity characteristics tend to be more important thansimilar regional characteristics. The share of cities ina country which has relatively little green and blue 27. Climate change challenges and response options26 Urban adaptation to climate change in Europeareas is particularly high in Hungary and Greece aswell as Cyprus, Estonia, Ireland, Luxemburg andSlovakia (Figure 2.2).Population density and the share of green/blueurban areas provide a reasonable initial estimatefor UHI at the city level and can also serve as aEuropean overview on potential hotspots. For morecomplex city planning it is clearly too simplistic.Additional factors and variations with the cityneed to be taken into account. Regarding the cities'0 20 40 60 80 100HungaryGreeceCyprusEstoniaIrelandLuxembourgSlovakiaFranceUnited KingdomGermanyItalyCzech RepublicSpainBulgariaRomaniaNetherlandsDenmarkAustriaBelgiumMaltaSloveniaPolandLithuaniaPortugalFinlandLatviaSwedenPercentage of cities in the country per classShare of green and blue areas of the city area 20 % 2029 % 3039 %= 40 %%Figure 2.2 Percentage of green and blue urban areas share of cities per class per country(based on Map 2.5)Note: Generally, only cities with more than 100 000 inhabitants are considered.sensitivity to heat not only is the share of green andblue areas important, but also their distribution,green facades and roofs as well as shadowing andventilation. Climate analysis of the city of Arnhem inthe Netherlands shows such an example (Map 2.6).The map clearly shows the variability of the riskrelated to heat in the city with red areas indicatingthe warmest city parts. The potential for ventilation(marked in black) is related to natural air flow alongrivers and on downwards trajectories. 28. Climate change challenges and response optionsUrban adaptation to climate change in Europe 27Map 2.6 Urban climate analysis map for the city of Arnhem, the NetherlandsSource: www.future-cities.eu.Social sensitivityThe majority of people in Europe live in urban areasand high population densities are already presentin European cities. The number of urban dwellerswill further increase in the near future (UN, 2010).As explained previously, some population groupsare more sensitive to heat than others. Of specialimportance in terms of sensitivity to heat are seniorcitizens aged 65 years and over. This populationgroup currently constitutes about 17.1 % of the totalpopulation of Europe, but this share is expected torise to 30 % by the year 2060. The share of peopleaged 80 years or older (4.4 % in 2008) will nearlytriple by 2060 (Schauser et al., 2010; Eurostat,2008). This demographic trend will naturally bringincreased heat-related mortality rates even withoutclimate change if no adaptation measures are taken.However, demographic development in cities doesnot necessarily follow regional trends. There are atpresent no European wide demographic projectionsavailable at the city level.Bearing in mind the many uncertainties sketchedabove, Map 2.7 and Figure 2.3 provide a firstimpression of European wide differences regardingthe social sensitivity of cities to heat. The mapshows the total population in 2004 and the shareof elderly people as a proportion of populationwithin the major European cities in Europe. Theproportion of elderly people in cities is higher incountries in the area of Europe stretching fromItaly to Germany and in northern Spain. In Belgiumand Germany this proportion usually follows thecountry average. Cities in northern Italy, meanwhile,tend to have values above the country average. Forother countries such as Bulgaria, France, Romania,southern Spain and the United Kingdom the shareof elderly people in most cities is lower than in ruralareas.The composition regarding age is not the onlyfactor that determines social sensitivity. Those onlow incomes, the disabled and sick, young childrenand ethnic minorities are classified as vulnerableUrban climatic analysismap of Arnhem cityFresh air areaCool air areaMixed climateOverheatingOverheating 2Overheating 3UMC classificationVentilationHigh potentialLow potentialBackground windsThermal inducedcirculationsTurbulancesabcd SubclassificationsAdministrativeborderMainroadsRailwaysdddbcbbbaba 29. Climate change challenges and response options28 Urban adaptation to climate change in EuropeMap 2.7 Vulnerable people the elderly are considered to be a group more sensitive to variousclimatic stress factors than people of a working ageNote: Total population in cities; proportion of population aged 65.Data for Bulgaria, Cyprus, Czech Republic, Finland, France, Ireland and Latvia are from 2001.Source: Eurostat, Urban Audit database, 2004.50 60 7040403030202010100-30 -20 -10 060505040400 500 1000 1500 kmVulnerable people the elderly are consideredto be a group moresensitive to variousclimatic stress factorsthan people of aworking ageProportion of aged population 65 in cities/countries, 2004Total population in cities,2004 100 000100 000250 000250 000500 000500 0001 000 000 1 000 000No data 1414151517 201720Outside datacoverage(Schauser et al., 2010). Further influences includesuch varied socio-economic characteristics as thequality of the health care system, availability ofheat-health warning systems as well as culturaland behavioural aspects. Such factors are alsointertwined with physical factors such as the qualityof the buildings (thickness of walls, isolation, oravailability of airconditioning), application of greenstructures in roofs and facades and accessibility ofpublic green and blue spaces (Harlan et al., 2006;Uejio et al., 2011).Potential future impactsClimate change projections indicate a rise in thenumber of heat-related deaths. The PESETA studyprojected almost 86 000 additional deaths per yearin 20712100 in the EU-27 Member States comparedto the 19611990 EU-25 average albeit under amuch more severe climate change scenario (EEAet al., 2008). Koppe et al., 2004 project a rise by upto 20 % until the year 2050 in Germany and Dessai(2003) by 35 % to six fold in Lisbon, Portugal. These 30. Climate change challenges and response optionsUrban adaptation to climate change in Europe 29Figure 2.3 Percentage of population aged 65 share of cities per class per country(based on Map 2.7)Note: Generally, only cities with more than 100 000 inhabitants are considered.0 20 40 60 80 100GermanyBelgiumItalySloveniaAustriaEstoniaSwedenSpainCzech RepublicPortugalLatviaUnited KingdomGreeceHungaryFranceFinlandNetherlandsBulgariaPolandCyprusDenmarkIrelandLithuaniaLuxembourgRomaniaSlovakiaPercentage of cities in the country per classShare of population age65 of total city population 20 % 1820 % 1617 % 1415 %14 %%deaths can be mainly expected in urban areas wherethe effects culminate. There are several intertwinedtrends climatic and non-climatic which makepopulation in cities more vulnerable to climatechange: global warming, increased urbanisation andpopulation ageing.Besides the impacts on health, a number ofsocioeconomic and environmental impactsresulting from higher temperatures and heatwaves,such as problems in energy supply and maintainingtransport services or water supply, will occur(Schauser et al., 2010). These can trigger additionalsocio-economic challenges in the form of lowerproductivity, failure of services, higher energydemand for cooling etc. There is currently notenough information available to assess these futureimpacts in cities across Europe.In addition, higher temperatures trigger certain airquality problems in cities. Part of the health effectsand increased rate of mortality resulting fromheatwaves may be caused by decreased air quality inthe urban environment (Box 2.6). 31. Climate change challenges and response options30 Urban adaptation to climate change in EuropeBox 2.6 Air quality problems due to higher temperaturesAir pollution in urban areas not only places additional stress on humans, but some pollutants have synergies withheat (Nawrot et al., 2007). Hot weather exacerbates air pollution through increased formation of ground-levelozone and, because hot periods usually coincide with dry periods, more particulate matter remains in the air(EEA, 2010d). Evidence for a synergistic effect on the mortality rate due to high temperatures and ozone-levels isincreasing (Bell et al., 2005; Medina-Ramn et al., 2006; Stedman et al., 1997). Hence, part of the health effectsand increased mortality during heatwaves may therefore be caused by decreased air quality (Filleul et al., 2006).Previously, hot, dry summers with long-lasting periods of high air pressure over large parts of Europe led toelevated concentrations of ozone which exceeded the minimum threshold values for health risks. Analysis on anumber of cities in the United Kingdom showed that between 21 to 38 % of those affected were not caused byheat, but by smog and particulate matter (Stedman, 2004). A study of a severe heatwave in Greece in 1987showed that the effects in Athens were much stronger than in other, less polluted Greek cities (Katsouyanni,1995)). Figure 2.4 shows a high percentage of the urban population affected by high ozone levels in 2003. Thiswas a year when large parts of Europe were affected by a heatwave (EEA, 2011a; EEA, 2011b). Increasingtemperatures and heatwaves in the future are expected to exacerbate the existing ozone problem. Forsberg et al.,2011 projects an increase of ozone-related deaths over the next 60 years in Europe, with 10 to 14 % increasebeing marked for Belgium, France, Portugal and Spain.Temperature is clearly not the only predictor of ground-level ozone concentrations. The main drivers are theconcentrations of ozone precursors: NOX and volatile organic compounds (VOCs). NOX are emitted during fuelcombustion for example by road transport and industrial facilities. VOC are emitted from a large number ofsources including paint, road transport, refineries, dry-cleaning and other solvent uses. Biogenic VOC are emittedby vegetation, with amounts released dependent on temperature. Methane (CH4), also a VOC, is released fromcoal mining, natural gas extraction and distribution, landfills, wastewater, ruminants, rice cultivation and biomassburning (EEA, 2011b). Further reducing the emissions of ozone precursors is therefore an option to reducingperiods with high ozone levels and adopting adaptation measures to more frequent heatwaves and warm weatherperiods in the future. NOX and VOC emissions also need to be reduced in order to protect the population againstthe resulting direct health impacts.Typical measures to improve air quality are therefore also supportive when coping with higher temperatures andheatwaves. These include the promotion of walking, cycling and the use of public transport; restrictions for roadtraffic; use of cleaner emission technology for transport, heating and cooling systems; creation of green areas,such as parks, can absorb and filter dust and other pollutants; and awareness raising and educating vulnerablegroups to avoid certain activities during events of high air pollutant concentrations (CoR, 2011a; EEA, 2010b;VTI, 2011).02550751001997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009% of urban population0 days 025 days 2550 days50 daysFigure 2.4 Percentage of the EU and EEA-32 urban population potentially exposed to ozoneconcentrations over the target value threshold set for protection of human health,19972009Source: EEA, 2011c (CSI 004). 32. Climate change challenges and response optionsUrban adaptation to climate change in Europe 312.1.3 How can cities adapt to heat stress?The use of grey infrastructure cooling forbuildings and urban areasDue to the expected increase in the number of hotdays and heatwaves, it is anticipated that demandfor air conditioning will increase. However, anincrease in the use of air conditioners producesadditional heat outside buildings and generatesmore greenhouse gases. Therefore, passive measuresto provide cool spaces should be considered first building designs that keep rooms cool via insulation(thick and well-designed walls, small windows,double glazing and the correct choice of materials)or blinds and public space providing shade andnatural ventilation.It is common that insulation measures are alreadyconsidered as ways to reduce energy consumptionand mitigate climate change. Integrating theadaptation concerns would provide even greaterbenefit to these measures. In the event that activecooling of buildings continues to be necessary,the most energy efficient air conditioning systemsshould be used and promoted through the EcoLabelling Directive (EC, 2000a) and awareness raisingcampaigns. District cooling is also an energyefficientway to prioritise absorption cooling (which allowsthe use of excess heat from other processes) overcompression cooling (which mainly uses electricenergy). In Vienna, as well as in Dresden, district andlocal cooling are combined together.Table 2.3 Overview on grey, green and soft adaptation measures to heatwaves following thestructure of Box 2.2Grey measures Green measures Soft measures Building insulation to keepthe inside cool Blinds to provide shade Passive cooling of buildings Urban designs providingshade Ventilation of urban space byintelligent urban design Emission reduction of airpollutants Boosting green infrastructure,such as green urban areas,trees, green walls and roofswhere possible, but ensuringsustainable watering Ensuring that fresh air fromgreen areas outside the citycan flow in General awareness raising and ensuring broad participation Mapping of urban heat island as well as cool places Identification of vulnerable groups and their distribution asbasis for targeted action Warning systems Heat action plans including appropriate institutional structures Preparedness of health and social care system Information on adapting behaviour during heatwaves inparticular to the vulnerable Adapting building codes to include insulation and shadowingto cope with heatwaves Consider reducing heatwave impacts through urban renewalprojects and urban planning Transport management to reduce air pollutantsThe use of green infrastructureConservation and improvement in existing greenand blue areas in cities and the creation of newspaces to ameliorate the urban heat island effectis hugely important and can have a number ofadditional benefits such as creating areas forrecreation, biodiversity, filtering air and drainingand storing water. Vegetation provides coolingthrough shading and enhanced evapotranspiration.Parks and open water areas are essential. Green andblue roofs lower temperature in buildings duringthe summer through insulation and enhancingevapotranspiration. Vegetation areas have asignificant effect on the local climate as they incitethe production of fresh and cold air, particularlyat night, and have a thermally balancing effectduring the day due to a high percentage of trees(SustainableCities.dk). Box 2.7 provides an examplefrom Manchester with the issue being furtherelaborated in Chapter 3. The European Commissionencourages green solutions as well, consideringgreen infrastructure as an essential tool for climatechange mitigation and adaptation. Investing in andbuilding up green infrastructure needs smart andintegrated approaches to spatial planning to ensurethat Europe's limited land is turned into areascapable of providing multiple functions for natureand society (EC, 2012a).Green infrastructure needs to be established in acareful way. The selection of plants needs to considerlocal water availability and potential scarcity. 33. Climate change challenges and response options32 Urban adaptation to climate change in EuropeThe introduction of invasive alien species or thereplacement of natural areas by artificial green areascan have negative impacts on biodiversity.Soft measuresAwareness and behaviour changesAwareness of the local population regarding effectsof excessive heat on human health coupled withinformation on simple measures to prevent excessiveheat stress enhances a city's preparedness. Suchmeasures can reduce sensitivity to heat exposure atthe individual and community level. Simple heatwarning advices from 'avoid drinking alcohol' to'wear a hat' can be very effective (see Box 2.8 for aSwedish example).Box 2.7 Manchester, United Kingdom increasing green infrastructure helps to cool downThe modelling of surface temperatures in theconurbation of Greater Manchester has shown thatthey closely followed the pattern of areas covered byvegetation in the urban area. In town centres and areasof retail or industry (20 % vegetative area) the surfacetemperatures reached 31.2 C on a hot summer day.By contrast, in woodlands (98 % vegetative area) thesurface temperature was only 18.4 C. While climatechange will lead to an increase of temperatures in everypart of the city, green space will significantly buffer someof the predicted warming. By 2080, under a high CO2emissions climate change scenario, surface temperatureswould rise to 35.5 C in the town centres (+ 4.3 C),but just 21.6 C in woodlands (+ 3.2 C). If the amountof green space decreased by 10 % in town centres andother densely built-up areas, the surface temperatureunder the high emissions scenario could rise by as muchas 8.2 C by 2080 from the present 31.2 C. On theother hand, an increase of green areas by 10 % wouldkeep the maximum surface temperatures at nearlythe same level as the 19611990 baseline conditions(Gill et al., 2007).Thus, the quantity of green spaces in the city is important for managing temperatures and other climate changeimpacts. The on-going project by Manchester City Council, 'City Centre Green Infrastructure Plan', recognisesthis factor and identifies where urban greening is the most needed. It also identifies actions needed forimplementation. On a broader scale the Greater Manchester green infrastructure framework is currently beingimplemented addressing the areas of green space need and deficiency across the conurbation, with climate changeadaptation as one of the guiding principles.Source: http://www.greeninfrastructurenw.co.uk/resources/1547.058_Final_Report_September_2008.pdf.Health warning systems and heat action plansAwareness raising is usually one of the componentsof so-called heat action or heat warning plans(Ebi et al., 2004; S. Hajat et al., 2010). The WorldHealth Organisation Europe (WHO Europe) haspublished guidance on how to develop suchplans (Barredo, 2009; Matthies et al., 2008)). Thedevelopment of a Heat Health Watch WarningSystem (HHWWS) can be considered as a longterm option to address heatwaves and other hightemperature events. This usually comprises ofa menu of individual options to respond to andprepare for extreme temperature events. Successfulsystems comprise of An agreement of a leading body to coordinatea multipurpose, collaborative mechanismbetween bodies and institutions and to direct thechannelling of information flows in the event ofan emergency;Photo: Bogna Kazmierczak 34. Climate change challenges and response optionsUrban adaptation to climate change in Europe 33Box 2.8 Botkyrka, Sweden: Tips on what to do in the event of a heatwave Avoid unnecessary efforts. Assist with foodshopping. Stop immediately what you are doingif you become dizzy or tired. Seek help if you feelunwell. Avoid stressful and unnecessary travel plans.Remember that it is often cooler in the morning andhottest early in the afternoon. Do not stay in the sun. Choose cool and shadedplaces when you are outdoors. Stay, where possible, in air conditioned or coolrooms. Select the coolest room in the house andventilate during the night. Note that fans may cool down unless it is extremelyhot in the room then they can cause dehydration. Libraries, restaurants and shopping centres may beair conditioned. Take a shower every day to stay cool. Choose light clothes which 'breathe'. Drink adequate amounts, preferably before you get thirsty. Water is fine, but avoid alcohol and very sweetdrinks. Overly cold drinks can cause cramps. Request medical advice on fluid intake or if you use diuretics, askyour doctor about the appropriate action. Avoid hot drinks or eating overly hot food as this raises the body temperature. Replace salt and minerals in your body if you sweat heavily. Mineral water and sport drinks work well. Keep in regular contact with relatives, friends or neighbours. If you are old or sick, ask someone to stay intouch with you. Follow weather reports and bear in mind that health problems increase with an average daily temperature formore than two consecutive days over 2223 C.Source: Botkyrka kommun, 2011; http://www.botkyrka.se/Nyheter/Sidor/Vrmeblja-.aspx. Accurate and timely alert systems (systemstrigger warnings, determine the threshold foraction and communicate the risks); Heat-related health information plan (what iscommunicated, to whom and when); Reduction of indoor heat exposure (mediumandshort-term strategies; advice to the publicon how to keep indoor temperatures low duringheatwaves); Particular care for vulnerable population groups; Health and social care system preparedness(staff training and planning, appropriate healthcare and the physical environment); Real-time surveillance and evaluation ofmeasures (Matthies et al., 2008).After the heatwave of 2003 several countries suchas France, Hungary, Portugal, and the UnitedKingdom established national HHWWS. In Spain aHHWWS was established at the regional level in theprovince of Catalonia. Such systems already exist inseveral German federal states and the Netherlands.A number of municipalities across Europe haveestablished similar systems adopting those elementsfrom those national plans relevant and feasible forthem (e.g. Madrid, Barcelona, Paris, Lyon, Marseille,Rome, Milan, Verona, London and Budapest. The'Heat Alert' system in Budapest is coupled witha smog alert system and an UV alert system. Itshowed success in 2007 when mortality rates due tothe extreme event had been lower in comparison to asimilar period in 2003 (Paldy and Bobvos, 2010).Photo: Sekkha 35. Climate change challenges and response options34 Urban adaptation to climate change in EuropeStakeholder involvementAll relevant municipal stakeholders (e.g. municipaldepartments, public health services, meteorologicalservices, hospitals and other medical institutions,schools, kindergartens, transport companies, massmedia, local environmental protection organisationsand companies) have their own 'protocol ofactivities' and the mandate to carry out these actionsin the event of a heatwave. In Paris the city council'sclimate plan enc