7.3.1 The Quasi-federal Nature of the EU

The EU has many federal features (Palermo Reference Palermo and Kincaid2019). These include the ideological roots of the EU integration project (Burgess Reference Burgess2000); many EU principles (e.g., the precedence of EU law over national law; the direct effect of EU law in the national legal systems and between citizens; the principles of loyal cooperation, conferral, subsidiarity, and proportionality; the distribution of powers, infra); and a consistent part of EU constitutional terminology (e.g., terms such as pre-emption, supremacy, exclusive and concurrent powers, residual clause). In particular, the EU appears to resemble more the model of administrative federalism (Börzel Reference Bogojević2005; Burgess Reference Burgess2000; Kincaid Reference Kincaid1999; Schütze Reference Schütze2009), as most of legislative powers in the EU are currently shared (e.g., environment, climate, energy), and responsibilities for policy execution mostly rest with the Member States. Significant elements of federalism are still missing in the EU integration process, however. For instance, the hierarchical relationship between the EU and the MS, with the former prevailing over the latter (MacCormick Reference MacCormick1999), is far from being settled and requires continual adjustment (infra).

Thus, throughout the long-running European integration process, the EU has been described by scholars as: sui generis (Mason Reference Mason1955; Phelan Reference Phelan2012; Wallace and Wallace Reference Wallace and Wallace2000); a system of multi-level governance (Hooghe and Marks Reference Hooghe and Marks1996, Reference Hooghe and Marks2001; Piattoni Reference Piattoni2010); an incomplete, supranational constitutional creature (MacCormick Reference MacCormick1999; Walker Reference Walker, Rosenfeld and Sajó2012); a supranational federation (von Bogdandy Reference Wettestad, Eikeland and Nilsson2012); an asymmetric integration process (Palermo Reference Palermo and Kincaid2019).

The debate has also been addressed by the Court of Justice of the EU (CJEU) and by the constitutional courts of several MS, each asserting a different perspective on the sovereignty issue.¹¹ These ‘judicial dialogues’ are not yet concluded and represent a specific feature of the evolving EU process of integration (Krommendijk Reference Krommendijk2020; De Witte et al. Reference De Witte, Mayoral, Jaremba, Wind and Podstawa2016).¹²

7.3.2 Architecture of the EU

The EU’s institutional architecture is based mainly on two orders of government: the EU and the Member States. However, the MS’s regional and local levels are increasingly gaining institutional representation at EU level (e.g., through the Committee of the Regions). In particular, the European Commission has sought to incorporate regions into the policy process – both to increase policy effectiveness and to enhance its visibility and legitimacy at the regional level (Keating Reference Keating2017).

In general, the European Council defines the EU’s overall political direction and priorities and includes the heads of state or government of the EU MS. MS defend their own national interests in the Council of the European Union, where the relevant national ministries meet and have the authority to commit their governments to the actions agreed on in the meetings, while the interests of the EU are promoted by the European Commission, where politically independent members (from MS’ national governments) sit.

The EU Treaties (i.e., the Treaty on the Functioning of the European Union, TFEU, and Treaty on European Union, TEU) codify some typical federal principles, such as loyal (‘sincere’) cooperation (art. 4.3 TEU), conferral, subsidiarity, and proportionality (art. 5 TEU). Four types of powers are listed (arts. 3–6 TFEU):

1. (1) exclusive, only the EU can act;

2. (2) shared between the EU and MS, such as on environment and climate change (art. 191–3 TFEU);

3. (3) those where the EU sets up arrangements and MS must coordinate;

4. (4) those where the EU can support, coordinate, or supplement MS’s actions.

7.3.3 Climate Change and the EU Division of Powers

Since 2009, the Treaty of Lisbon has introduced a new EU shared power on energy in art. 194 TFEU (Benson and Russel Reference Benson and Russel2015), which was before exerted by the EU on the basis of various provisions scattered throughout the Treaty, paradoxically allowing a wider margin to the EU (Fehling Reference Fehling2021; Jegen Reference Jegen2014).¹³ Therefore, climate and energy measures can be based on both environment (art. 191–3) and energy (art. 194) provisions with two main caveats.

First, whereas the ordinary EU legislative procedure applies to both cases of shared competences, MS may adopt more stringent protective measures than those set at the EU level only according to art. 193 TFEU, not under art. 194 TFEU. For instance (art. 191–3), being the legal basis of the Effort Sharing instrument, under this system MS may maintain or introduce more ambitious targets than those set at the EU level.

Second, the sovereignty clause included under art. 192.2 (i.e., environment and climate competence) foresees that some EU measures may be adopted by the Council unanimously, with a special legislative procedure: for instance, provisions primarily of a fiscal nature, measures affecting land use, and those significantly affecting a MS’ energy sources choices and the structure of its energy supply (thus derogating to the sovereignty clause of art. 194.2, which prescribes that EU measures ‘shall not affect a MS’ right to determine the conditions for exploiting its energy resources, its choice between different energy sources and the general structure of its energy supply’). To this regard, art. 194 TFEU, in addition to other political drivers (Bürgin, Reference Bürgin2014, Rayner and Jordan Reference Rayner and Jordan2016), has directly affected the shift from MS’s binding renewable energy targets under the 2020 Package to an overall binding target at EU level under the 2030 Framework. In fact, the legal basis used for adopting the new 2018/2001 Directive ‘on the promotion of the use of energy from renewable sources’ was art. 194, instead of art 191 TFEU (which was the legal basis for previous renewable energy Directive 2009/28). In other terms, the adoption of MS legally binding targets under the new 2018/2001 Dir. would have likely violated the boundaries set under art. 194.2 TFEU.

Considering the interdependencies between environment, climate, and energy policies and the ‘grey areas’ left by arts. 191–4 TFEU, the relationship between EU and MS powers regarding climate-related acts is subject to varying interpretation and political compromises. An example of this ambiguity is offered by the Governance Regulation, which has a double legal base (i.e., both art. 191 and 194 TFEU), thus leaving room for uncertainty on several points (e.g., the application of sovereignty clauses and of national reinforcements of protection) (Fehling Reference Fehling2021).¹⁴ On the other side, it should be noted that the Governance Regulation aims at linking the EU climate policies and the so-called Energy Union (a framework strategy launched in 2015 to bring about the transition to a low-carbon, secure, and competitive economy) by integrating Member States’ planning and reporting obligations with regard to climate and energy (infra).¹⁵

After EU climate and energy binding acts (e.g., directives and regulations) are adopted, MS are responsible for implementing and enforcing them at national level. The European Commission monitors this implementation and has the power to commence infringement procedures (art. 258 TFEU), which can lead to a case being filed before the CJEU.¹⁶ Poor or delayed implementation of EU environmental legislation, including climate and energy related acts, has being a constant feature of the EU legal history.¹⁷ The opposite case of MS contesting the Commission, also occurs, for example when some MS’s appealed against the Commission’s powers to review MS’s National Allocation Plans of emission allowances (Bogojević Reference Bogojević2010, Reference von Bogdandy, Jones, Menon and Weatherill2013; Damro et al. Reference Oberthür and Kelly2008).¹⁸ Because of the national challenges against the Commission’s decisions and the subsequent legal uncertainty, since 2013 this decentralized, bottom-up process has been substituted by an EU-wide cap.¹⁹

Besides infringement procedures, ‘softer’ enforcement mechanisms (i.e., ‘iterative processes’ or ‘dialogues’ or the ‘Open Method of Coordination’) exist under EU law in areas where powers remain at the MS level and EU binding measures cannot be adopted. Such mechanisms rely for their success on the cooperation of MS (Smismans Reference Smismans2011). Under this soft approach, objectives are set at EU level through recommendations, standard-setting, benchmarking, peer review, and best practices (Ringel and Knodt Reference Ringel and Knodt2018), while decentralized implementation responsibilities rely on MS. The European Commission has consecutively applied these mechanisms to build a structured dialogue with the MS especially in the energy efficiency and renewable sectors, where binding national targets could not be adopted (art. 194.2 TFEU). The aim has been to cajole national energy policies towards more ambitious decarbonization targets, and somehow overcome political divisions between different MS on energy and climate priorities within the Council (Knodt, Ringel, and Müller Reference Knodt, Ringel and Müller2020). The 2018 Governance Regulation enhances these soft governance arrangements by incorporating harder elements (infra, Section 7.4.1).

7.4.1 The EU as an ‘Opportunity Structure’ for Policy Innovation, Diffusion, and Interactive Learning

As expected, the EU offers an interesting combination of different (federal) features and represents an ‘opportunity structure’ for policy innovation, rapid policy diffusion, and interactive learning in the field of mitigation (Jänicke and Quitzow Reference Jänicke and Quitzow2017; Meyer-Ohlendorf et al. Reference Meyer-Ohlendorf, Duwe, Umpfenbach and McFarlane2014). Over time both competitive and cooperative forms of governance have driven mitigation policies. MS, especially those most economically efficient and the ‘frontrunners’, have been facilitated in promoting their interests and pioneer policy choices into EU climate action, while the supranational framework has guaranteed a common arena for mutual learning, gradual convergence around common mitigation objectives in light of considerations of solidarity, and ‘differentiated responsibilities’ (Fehling Reference Fehling2021; Rayner and Jordan Reference Rayner and Jordan2016), through funding and supporting mechanisms, thus ‘leaving no one behind’.²⁰ The institutional architecture and the mitigation policies of the EU reflect this mix of decentralized, flexible, competitive, bottom-up approaches, in addition to cooperative and supranational coordination elements, and present both opportunities and challenges as illustrated by the following examples.

Over time, climate policy has become an important driver of EU integration, especially after the increasing support for European-level action in this field showed in public opinion polls and by green parties and environmental NGOs (Oberthür and Roche Kelly Reference Damro, Hardie and MacKenzie2008; Schreurs and Tiberghien Reference Schreurs and Tiberghien2007).²¹ EU leadership has been driven by such a combination of events, and in turn by the (reinforcing) competing role of mutual leadership played by several MS, for instance, Germany, the UK, the Netherlands, and Denmark, but also Finland and Sweden.

Several MS have anticipated and influenced the EU’s climate mitigation initiative and consequently that of other MS, pushing European climate mitigation policy forward while at the same time gaining credit for their actions domestically. This has occurred, for instance, by establishing governance frameworks with a long-term outlook through the adoption of national climate laws (including some adaptation measures as well), also referred to as ‘flagship laws’ (Fankhauser et al. Reference Fankhauser, Gennaioli and Collins2015). The UK’s pioneering 2008 Climate Change Act inspired a range of related national framework laws, although the Paris Agreement may have accelerated this diffusion (Duwe and Evans Reference Duwe and Evans2020).²² Emulation was a major mechanism shaping climate framework laws developed in other MS after the UK example (Evans and Duwe Reference Evans and Duwe2021; Meyer-Ohlendorf Reference Meyer-Ohlendorf2020). Thus, peer behaviour can be confirmed to have encouraged diffusion in this context, revealing that framework legislation entails a ‘signalling character’ as it provides for further negotiations (Fankhauser et al. Reference Fankhauser, Gennaioli and Collins2016) and offers an indicator for further climate change legislation.

Most MS’ national mitigation policies and measures have been implemented in response to EU strategies and to binding instruments (e.g., the 2009 Renewable Energy Directive, the 2012 Energy Efficiency Directive, the Effort Sharing Decision).²³ Only 27 per cent of reported national actions are not directly related to a specific EU policy or legislation.²⁴ However, since MS have adopted climate mitigation policies and legislation of varied ambition, taking advantage of the flexibility of EU policy and of binding instruments on mitigation (directives), as well as of the autonomy of MS in the energy field (i.e., subsidiarity and sovereignty clause), some delays in adopting mitigation measures as well as implementation variances across MS occurred (Fleig et al. Reference Fleig, Schmidt and Tosun2017).²⁵ Thus, EU mitigation policies do not convey such a coherent, homogeneous, and ambitious approach as one would have expected, for instance, based on the EU’s climate change leadership aspiration (Gupta and Ringius Reference Gupta and Ringius2001; Massey et al. Reference Massey, Biesbroek, Huitema and Jordan.2014; Parker and Karlsson Reference Parker and Karlsson2010; Rayner and Jordan Reference Rayner and Jordan2016). Especially because of the 2004 problematic enlargement to include formerly communist central and eastern countries, dominated by fossil fuel energy programmes, the EU’s mitigation policy ambition has at times been limited (infra), and has been only partially reinstated through substantial financial compensation and exemptions (Kulovesi and Oberthür Reference Kulovesi and Oberthür2020; Peeters and Athanasiadou Reference Peeters and Athanasiadou2020; Rayner and Jordan Reference Rayner and Jordan2016).

7.4.2 The ‘Competitive Cooperation’ between the Council and the Commission

Member States’ diverging priorities and sometimes conflicting positions are reflected, in turn, into the European Council and into the Council of the EU, where MS heads and MS ministers respectively reaffirm their sovereign priorities, sometimes in contrast with that of the European Commission. For instance, in the European Council of June 2019, Poland, Hungary, Slovakia, and the Czech Republic opposed the proposed target of zero emissions, thus hampering a 2050 carbon neutrality target for the EU. Ongoing clashes among national sovereignty over energy policies (Herold et al. Reference Palermo and Kincaid2019; Marcinkiewicz and Tosun Reference Marcinkiewicz and Tosun2015; Szulecki Reference Szulecki, Fischer, Gullberg and Sartor.2016) hinder to some extent the EU’s mitigation aspirations. Moreover, clashes among MS in the Council and the Commission illustrate a peculiarity of the EU’s governance system – the ‘competitive cooperation’ between the Council and the Commission in legislative agenda setting (Bocquillon and Dobbels Reference Bocquillon and Dobbels2014).

To reconcile these opposing positions and negotiate a pan-EU climate change mitigation goal, the strategy that EU institutions seem to pursue is based on collective actions where all MS participate in the mitigation efforts, while considering national circumstances and concern of fairness and solidarity. This approach has been applied throughout numerous European instruments, such as EU legislation (e.g., EU ETS, Effort Sharing), specific financial mechanisms (e.g., the Modernisation Fund, supporting investments for a just transition in carbon-dependent regions in ten lower-income Member States), financial assistance through existing funding schemes (e.g., structural and investments funds), and increasing instruments combining research, innovation, and funding (e.g., Just Transition Platform, NER 300 programme), which create networks for MS, regions, agencies, and stakeholders to exchange information and knowledge, good practices, and specific assistance to meet collective targets.²⁶

Some national sovereignty instances over energy transition continue to hinder not only the integration of European energy policies and the Energy Union, but also the coherence and effectiveness of European mitigation action (Mata Pérez et al. Reference Pérez, Scholten and Stegen2019).²⁷ Nonetheless, the package of flexible instruments described above constitutes a sound attempt to contrast the 2004 problematic enlargement dimension of the EU with regard to energy governance fragmentation and the increasingly difficult intergovernmental decision-making in climate policy (Rayner and Jordan Reference Rayner and Jordan2016) previously mentioned. Some scholars have also suggested that the Governance Regulation constitutes an attempt by the Commission to overcome the hard confrontation between the two blocs of MS, the Visegrad and Green Growth Groups, and to improve MS’ planning and reporting gaps by introducing an integrated framework and a ‘harder form of soft governance’, exemplified by the ‘blank cheque’ (Ringel and Knodt Reference Ringel and Knodt2018).²⁸

In other terms, in the event of insufficient ambitious national plans or progress towards the energy and climate targets on the part of MS, the Commission is entitled to adopt additional measures, legislative acts, and exercising powers at the EU level (Knodt, Ringel, and Müller Reference Knodt, Ringel and Müller2020; Oberthür Reference Oberthür2019). So, in case of delivery gaps, EU intervention over MS’s energy mix choices would be justified, thus bypassing the sovereignty clause of art. 194.2 TFEU, and within the boundaries of the subsidiarity and proportionality principles (Monti and Martinez Romera Reference Duwe and Evans2020). Recalling that the Renewable Energy Directive (2018/2001) and the Energy Efficiency Directive (2018/2002) define Union-wide targets for 2030, instead of national individual ones, the new means of the Commission to advance MS policy implementation under the Governance Regulation balance the additional flexibilities granted in favour of MS (Monti and Martinez Romera Reference Duwe and Evans2020; Oberthür Reference Oberthür2019).

In this respect, some scholars have also observed a trend towards a gradual increase of European Commission authority over MS external energy policies (a power not explicitly conferred to the EU under art. 194 TFEU), culminating with the adoption of Decision 2017/684.²⁹ The Commission has started to influence MS’ negotiations over energy imports and relations with third parties through soft pre-emptive compliance instruments, such as ex ante checks that prevent non-compliance with EU rules, guarantee the integrity of the internal energy market, and allow the Commission to gain supranational governance capacity in the energy realm (Dehousse Reference Dehousse2015, Thaler and Pakalkaite Reference Thaler and Pakalkaite2020). In this context, more recently, the Council has invited the Commission to prepare a new strategy on external action in the field of energy cooperation in light of a rapid shift towards the climate neutrality goal.³⁰

Previous examples shed light on the drivers of the EU integration process and on the current challenges for a coherent European mitigation policy. The evolving powers of the European Commission tend to be described in contrast with those of MS, which are mainly shaped by national economic interest (in addition to political cultures and regulatory styles: Hoppe and Wesselink Reference Hoppe and Wesselink2014; and constitutional design: Steurer and Clar Reference Steurer and Clar2015). On the other side, the Commission’s role is confronted with MS interplay and changing equilibrium in the European Council. Thus, some scholars describe these processes as polarised and disconnected instead of being complementary dynamics in a complex EU governance (Schmidt Reference Schmidt2016), while others underline that the decentralized and multi-level governance structure of the EU has encouraged a process of mutual reinforcement, where MS and the European Commission are competing (Schreurs and Tiberghien Reference Schreurs and Tiberghien2007) or mutually supporting (Bürgin Reference Bürgin2014) for leadership.

7.4.3 Multilevel Reinforcing Mechanisms: Linking the EU and Regional/Local Governments and Communities

Over time the Commission has enabled and built on multiple dynamics (both vertical and horizontal ones) to exert increasing influence towards ambitious mitigation actions. This multi-level and multi-sectoral approach in targeting industries, mobilizing economic interests, involving sub-national authorities and domestic stakeholders across levels of governments (Szulecki et al. Reference Szulecki, Fischer, Gullberg and Sartor.2016; Wettestad et al. Reference Wettestad, Eikeland and Nilsson2012), has empowered EU mitigation policies by directly linking European goals with domestic and local support and with industry interests for climate-friendly technologies. To this extent, the ‘Europe 2020’ Strategy, the ‘2020 Climate and Energy Package’, and the ‘2030 Climate and Energy Framework’ have put special emphasis on strengthening the interconnections among the industrial sectors, the research community, and financial resources and specific funding programmes (e.g., NER 300 and NER 400; Innovation Fund and Modernization Fund), aiming at EU low-carbon objectives.³¹ Some scholars have noted that these multi-level reinforcing mechanisms are equally present in ‘frontrunners’ and ‘laggards’ MS (Jänicke and Quitzow Reference Jänicke and Quitzow2017) and provide forums for benchmarking, especially in the framework of soft governance mechanisms, as well as an opportunity structure for innovation and experimentation, interactive learning, and best-practices diffusion.

To this same end, the European Commission has pushed for a greater emphasis on regional and local governments of MS in tackling mitigation. In 2008 the European Commission, with support of the Committee of the Regions, launched the EU Covenant of Mayors initiative.³² This initiative has become a well-established network of cities and towns committed to implementation of the EU’s GHG-reduction target by 2030 (e.g., by submitting energy and climate action plans and by taking actions in policy areas directly influenced by local administration).³³ Furthermore, the European Commission has recognized the role of MS’ provincial and regional government levels as Covenant Territorial Coordinators (CTCs) in supporting municipalities with strategic guidance, financial aid (e.g., through ERDF and Cohesion Fund) and technical support. The CTCs, in some cases, even compensate for the void left by the national level, that is, the absence of MS frameworks for local energy planning. Thus, these local-level initiatives, supported by the European Commission, play an important role in reinforcing mitigation policies in pioneer MS (e.g., Germany, Denmark, the UK) and in filling the gaps in laggard MS (e.g., Poland) with weaknesses at the national level (Jänicke and Quitzow Reference Jänicke and Quitzow2017). In addition, a reduction of high administrative fragmentation has been observed in some MS (e.g., in Spain, Italy, and Belgium) (Melica et al. Reference Melica, Bertoldi and Kona2018).

Another advantage partially derived by this tighter vertical coordination network is reflected in the improved capability of local level governments to promote and finance sustainable energy projects. Also, the EU Covenant of Mayors initiative and the CTCs system have been observed to catalyse dynamic processes of policy diffusion (Grafakos et al. Reference Grafakos, Viero and Reckien2020; Kona et al. Reference De Witte, Mayoral, Jaremba, Wind and Podstawa2016; Melica et al. Reference Melica, Bertoldi and Kona2018), and to influence local entities persistently, for example, through baselines, guidance documents, regular communications and templates which push towards convergence (Heyvaert Reference Heyvaert2013). The transparency of the Covenant system also creates opportunities for ‘naming and shaming’, thus increasing the compliance of local entities (Kona et al. Reference De Witte, Mayoral, Jaremba, Wind and Podstawa2016). At the same time, the Covenant promotes some flexibility and differentiation among the local entities aiming at the development and implementation of climate mitigation and sustainable energy actions which are innovative and tailored to local circumstances.

7.5.1 The EU Initiative and Financial Assistance as Key Factors to Catalyse Adaptation Action in Member States

The EU initiative on adaptation (2013 EU Adaptation Strategy, followed by the new 2021 Strategy) only encourages MS, regional, and local levels to take action, rather than mandating it, as the EU lacks formal authority in a variety of areas related to adaptation (Fleig et al. Reference Fleig, Schmidt and Tosun2017).³⁴ Thus, cooperation among MS and coordination with the EU play a prominent role. The European Commission, in particular, provides financial assistance to MS adaptation initiatives, monitors and assesses the national adaptation strategies, and supports the MS and their government levels through the European Climate Adaptation Platform (Climate-ADAPT), which allows the exchange of data, good practices, and information.³⁵

It should be noted that in the adaptation field several EU MS adopted strategies and framework legislation including provisions on adaptation earlier than the EU.³⁶ The increasing costs and damages associated with more frequent extreme weather events such as floods, storms, and heatwaves, recorded in MS and gaining increased public awareness and attention (Lorenzoni and Hulme Reference Lorenzoni and Hulme2009) have propelled these MS’ early adaptation actions.³⁷ In addition, according to some scholars (Fleig et al. Reference Fleig, Schmidt and Tosun2017; Russel et al. Reference Duwe and Evans2020), diffusion of adaptation policies and laws in other ‘laggard’ and ‘wavering’ countries has been observed as a ‘Nordic-country effect’; in other terms, the early adoption of such laws in Nordic countries has affected the diffusion of adaptation frameworks in other EU MS. In the EU context, peer behaviour has been quite influential thanks to the spread of ideas, practices, and institutions (Massey et al. Reference Massey, Biesbroek, Huitema and Jordan.2014).

However, the steady increase over five years (2013–18) of national adaptation strategies and plans in the EU MS is strongly influenced by the EU Adaptation Strategy, adopted by the Commission.³⁸ In fact, the EU initiative has catalysed action in MS and particularly in those that were in earlier stages of developing an adaptation policy. The EU’s facilitative role through providing guidance, funding research and adaptation action under the Strategy has urged and enhanced MS initiatives (Massey and Huitema Reference Massey and Huitema2016). In particular, in central and eastern MS, the most important driver for diffusion of adaptation measures was the EU’s effort to put adaptation on the MS agenda and the accompanying financial support (Massey et al. Reference Massey, Biesbroek, Huitema and Jordan.2014).

The EU’s efforts to promote adaptation across MS have intensified in recent years, for instance by establishing mechanisms of knowledge sharing and best-practices exchange among public and private stakeholders of MS (i.e., through the Climate-Adapt Platform), by the involvement of MS’ local governments to engage in adaptation initiatives on the basis of voluntary commitments, and by providing financial support through existing European funds (e.g., the EU’s Solidarity Fund). In this respect, EU funds play an important role as there is a lack of funding, with only half of Member States having budgets attached to their adaptation instruments (i.e., National Adaptation Strategies, NAS, and National Adaptation Plans, NAP).³⁹ In addition, since the EU only encourages MS to adopt comprehensive adaptation strategies, a recent factor influencing MS’ action could be detected in the Commission’s intention to adopt a legally binding instrument in the event that the progress of MS is insufficient.⁴⁰ Some hints of coercion, in the long run, can be perceived as an additional driver for the spreading of adaptation action in MS, as hard law equips the EU Commission with the power of initiating infringement procedures in case of non-compliance, while soft governance only relies on the active cooperation of MS.

Vertical coordination among European, national, regional, and local authorities is essential, as current financial and knowledge gaps at the local level may hinder local action. However, systematic coordination across all levels of administration has only been observed in some MS, while gaps in the involvement of sub-national governance levels have been detected in other MS.⁴¹ In 2014, the European Commission launched a separate initiative called Mayors Adapt, based on the EU Covenant of Mayors experience (see above). This had the aim of engaging cities in taking action to adapt to climate change, either by developing comprehensive adaptation strategies or by integrating adaptation to climate change into their relevant existing plans. In 2015, the two initiatives officially merged into the Covenant of Mayors for Climate & Energy and now represent successful experiences (Kona et al. Reference Kona, Melica and Bertoldi2017) of vertical (local and regional linking to national/EU levels) and horizontal (e.g., national and transnational city networking, learning and best practices sharing) collaboration for mitigation and adaptation actions.⁴² At the local level, involvement in the EU Covenant of Mayors for Climate and Energy has proven to be effective in promoting city-level adaptation policymaking and in linking the EU strategy with local action. In some cases, further support is assured by national and regional initiatives (Grafakos et al. Reference Grafakos, Viero and Reckien2020). For instance, the Ministry of the Environment of Czech Republic has officially committed to providing strategic guidance, financial and technical support to local authorities that are signatories to the Covenant and has been recognized by the European Commission as a Covenant National Coordinator. These cases further exemplify how, over the years, the EU has established collaborative policy frameworks, networks facilitating mutually supportive schemes, and knowledge sharing and financial support mechanisms across government levels.

7.5.2 Adaptation as a Cross-Cutting Policy Area across Multiple Scales: Progress and Challenges

In this realm, the transnational cooperation among MS (plus third countries) has also increased with the recognition of the importance of adaptation as a cross-cutting policy area. Notably, EU-driven transboundary adaptation action is channelled through four macro-regional strategies, thus involving most MS.⁴³ For instance, the EU Strategy for the Danube Region emphasizes adaptation to extreme weather events and provides an important platform to foster cooperation on joint monitoring and flood management. At the same time, this cooperation facilitates the collective implementation of existing EU directives and sectoral policy which, in turn, contribute to efforts for adaptation to climate change with regard to water issues. This case is replicated in the other European macro-regions regarding other sectoral policies and related adaptation initiatives. For instance, multiple initiatives addressing adaptation to climate change exist for mountain ranges and for biodiversity (e.g., Alpine space).⁴⁴

These examples illustrate the process of mainstreaming adaptation action into the EU’s sectoral policies at different levels, by supporting environmental policy integration practices across multiple scales (Heyvaert Reference Heyvaert2013; Jordan and Lenschow Reference Jordan and Lenschow2010), and the process of ‘multi-level reinforcement of policy action’ in the EU climate change adaptation field. Nonetheless, some policy sectors, such as marine and coastal ones, though singled out as priorities in the EU Adaptation Strategy, receive less attention in terms of adaptation mainstreaming and do not fall into these virtuous dynamics mainly because of some MS’ conflicting agendas and preferences. Germany, for instance, has strongly opposed any policy action affecting marine and coastal planning issues from the European Commission (Russel et al. Reference Russel, den Uyla and de Vito2018). In addition, gaps at national and sub-national levels in introducing adaptation considerations in certain sectors are still relevant. Only a few MS have national policy instruments that promote adaptation at the sectoral level, in line with national priorities and in areas where adaptation is mainstreamed in EU policies.⁴⁵ A final aspect concerns knowledge gaps. Investment in the development of knowledge on climate adaptation is more likely in countries that already have a strong research base, and a greater critical mass (e.g., Germany, France, and the UK, as a former MS), while smaller countries and countries with a small research budget make progress by becoming involved in European research projects and by cooperating with other MS that face similar issues (Massey and Huitema Reference Massey and Huitema2016; Massey et al. Reference Massey, Biesbroek, Huitema and Jordan.2014; Russel et al. Reference Duwe and Evans2020).