Dilemmas in Statutory Urban Planning When Addressing the Climate Adaptation Implementation Gap: Insights from Six European Cities

Abstract

As the climate crisis intensifies, the urgency of climate adaptation is becoming increasingly evident, if not imperative. Adaptation efforts often fall short in implementation, revealing a critical gap in climate-responsive planning. This study investigates the potential of statutory urban planning instruments to enable climate adaptation and bridge the adaptation implementation gap. To tackle this challenge, we introduce the BRIDGE framework, operationalized using an indicator-based screening tool that integrates three dimensions of the planning practice—substantive, procedural, and contextual—with three foundational pillars—agility, robustness, and legal certainty—complemented by three adaptive planning factors—complexity, uncertainty, and flexibility. The tool was pilot-tested in six European cities to screen the capacity of recently approved land use plans to enable climate adaptation implementation. The findings confirm that the consideration of uncertainty is overlooked, as well as the ongoing assessment and tracking of risks and adaptive measures. These setbacks potentially hamper institutions’ ability to respond to evolving climate conditions and undermines the legal embedding of adaptation measures. Ultimately, this study reinforces the need to strengthen context-specific and scientifically grounded planning decisions, enable procedural and legal flexibility, and balance the tensions between strategic vision and regulatory enforcement of adaptation.

1. Introduction

Climate change is already underway [1] and is expected to intensify [2,3], driven by environmental, social, economic [1,3], and land use dynamics and decisions [1,2,4], with risks escalating beyond the 2 °C limit set by the Paris Agreement, potentially causing irreversible damage [1,5,6] and new hazards [2]. Delaying action reduces effectiveness, making timely measures essential to cut emissions, anticipate risks [1,4], prevent damage [4,7,8], and lower recovery costs [9,10]. This requires understanding territorial systems [1,11], acting on scientific evidence [12], adjusting societal processes to climate risks [11,13,14,15], addressing biodiversity loss [16] equitably and inclusively [17,18], and a deep shift in mindset and consciousness [19].

The EU’s climate adaptation framework, shaped by the Green Deal, Climate Law, and “Fit for 55,” strengthens adaptation with binding targets in key sectors such as agriculture, forestry, and buildings [20,21], national coastal strategies in member states [22], and better policy integration into energy, biodiversity, and finance [23]. The EU Adaptation Strategy, although not legally binding, influences legislation and funding priorities, aiming for a climate-resilient Europe by 2050 through smarter, faster, and systemic action, including nature-based solutions and global cooperation. The new integrated framework for climate resilience and risk management, to be adopted in 2026 and of a regulatory nature, will further align national efforts with the Paris Agreement. In this context, a significant responsibility lies at the municipal level to translate policy goals into tangible outcomes makes local governments crucial actors in implementing adaptation measures.

A growing body of theory and case studies has identified many common barriers to climate change adaptation, especially in spatial planning [24,25,26]. A fragmented and underdeveloped legal framework for adaptation, coupled with limited-binding commitments and uneven local implementation—frequently constrained by inadequate powers and resources—has been widely highlighted as a critical challenge [27,28,29,30,31]. In the last 10 years, increasing attention has been paid to the approaches and methods for mainstreaming adaptation [19] as a specific approach of adaptive planning [32,33,34], policy integration [18,35], climate proofing [32,36], and related methodologies and frameworks [18,19,27,34,37,38].

Despite this knowledge, there is little evidence that it has led to meaningful policy change or transformative action [1,19,27,39]. Misalignment between planning tools and climate goals persists [34], and climate considerations are still rarely fully integrated into formal urban planning processes or translated into concrete on-the-ground adaptation actions [27,29,40,41]. To date, local climate adaptation efforts in Europe have largely focused on voluntary, non-binding plans (e.g., Sustainable Energy and Climate Action Plan) that lack legal enforceability of adaptation and institutional support [18,29]. Without regulatory backing [30], these plans often fail to translate into effective action, limiting their long-term impact [41,42,43]. Beyond financing, this may hinder implementation, leaving adaptation measures inadequate for real needs [18,30,31]. As a result, market-driven, inequitable, and climate-inadequate planning persists, increasing vulnerability in cities and communities [20,29,43]. This gap between adaptation needs and actual actions, known as the “implementation gap”, has driven the call for better mainstreaming to support more sustainable and equitable development [1,19,27].

Against this background, our research specifically examines the potential role of statutory urban planning in effectively bridging the climate adaptation implementation gap. It addresses the following research questions: What are the critical elements in statutory urban planning that can contribute meaningfully to closing the gap? What is the relationship between these elements? Could the implementation gap be explained using these relations? To answer these questions, this study builds on the existing literature and mainstreaming approaches to develop a theoretical framework and an indicator-based screening tool for assessing the ability of statutory urban plans to facilitate climate adaptation. The focus of this study is on evaluating the potential of recently approved land use plans to enable climate adaptation, rather than assessing actual on-the-ground outcomes. The tool was tested in six cities—Bilbao, Mannheim, Liverpool, Warsaw, Vienna, and Paris—to evaluate its practical usability and potential for broader application.

This paper is structured as follows: Section 2 introduces the conceptual basis of the study—the so-called BRIDGE framework. Section 3 describes the materials and methods. Section 4 presents the results of the pilot test findings in the six cities. Section 5 discusses the results and the methodological challenges for future use. Section 6 concludes with recommendations for further research.

2. Conceptual Basis: The BRIDGE Theoretical Framework

This study adopts a pragmatic understanding of adaptation as the capacity for social-ecological systems to adjust to changing internal and external conditions [1] and resilience as the ability to maintain stability within critical thresholds while adapting [19]. Urban planning instruments in this study refer to formal, government-led statutory plans at the local level, often applied as a policy mix to guide development, balance competing interests, and coordinate cross-sectoral policies toward sustainable and equitable outcomes [44,45,46]. These plans are not only strategic documents, but also operational tools shaped by governance systems and social contexts [45]. This research is positioned within the broader discourse on hybrid planning approaches that focuses on rationalist (static) and incrementalist models [11,12,34,35].

The BRIDGE framework builds on established approaches to climate mainstreaming [24,29,31,43] and advances a systems-oriented perspective on transformative climate mainstreaming by emphasizing the systemic factors in statutory urban planning [19].

The theoretical framework BRIDGE is illustrated in Figure 1, inspired by the “planners triangle” of Campbell [47].

Three dimensions of planning theory underpin the framework: Substantive planning defines the content and goals of planning and their implementation [12,36,48]. Contextual planning considers the uncertainties and the socio-economic, spatial, and temporal contexts in which planning is carried out [45,49]. Procedural planning structures the processes of formulation, implementation, and evaluation, acting as the procedural envelope for the other two dimensions [12,36]. The framework places statutory urban planning at the core, focusing on how these instruments can support climate resilience by balancing (i) the agility of the planning process to address the urgency for climate action, (ii) the robustness of planning decisions, and (iii) the predictable governance and legal certainty in regard to the rights, obligations, and outcomes of planning processes in the face of climate change. Legal certainty comprises two interrelated dimensions:

• Material certainty, which refers to the clarity and predictability of the substantive content of rights and obligations.
• Procedural certainty, which concerns the transparency and foreseeability of the processes by which individuals may participate, raise objections, or lodge appeals—particularly in contexts where regulatory restrictions are subject to change. [50,51].

Finally, it incorporates three overarching and interconnected factors predominantly emphasized in the literature in connection with adaptive planning [44,52]: addressing complexity, embracing uncertainty, and allowing for flexibility. These align with widely recognized categories of implementation barriers, including governance (political will, power), resources (financial, technological, human), and institutional factors (awareness, data, skills, technology) [53]. In this study, cognitive and motivational factors at the individual level are excluded, as the analysis is based on public planning documents.

Addressing complexity requires an understanding of the interplay between financial, policy, socio-ecological, and territorial governance systems to adjust societal processes to current and future climate risks from a precautionary principle [7,44,54,55,56], offering co-benefits in health, environmental quality, adaptation, and mitigation [7,15,41,57,58,59,60,61]. In the climate change context, addressing compound, emergent (e.g., population shifts), cascading, and systemic risks [17] is essential for mitigating amplified climate impacts through integrated, resilient strategies [56,57,62,63,64]. Recognizing space not as static but as shaped by social and ecological interactions is critical, requiring public leadership and collective consensus in territorial transformation [65]. Addressing complexity also involves operating across multiple scales, sectors, and actors [19] and sensitivity to local contexts [13] while respecting natural processes [8] and promoting equity, ensuring the needs of vulnerable populations are not compromised [17].

Embracing uncertainty is inherent in spatial planning as a future-oriented discipline [1,11], further intensified by climate change. The growing need for climate risk assessments is challenged by deep uncertainty, where future conditions are too novel or complex for traditional probabilistic models [66], particularly regarding the timing, magnitude, and nature of impacts [56]. This stems from limited hazard data, inconsistent climate projections, and poor understanding of hazard–scenario interactions. Traditional predictive planning often fails under such conditions. Instead, planning under deep uncertainty relies on robust decision-making, scenario planning, and adaptive pathways across multiple plausible futures, as no single future can be reliably predicted [1], enabling ongoing adjustments and transformative opportunities [11]. A key challenge is the lack of standardized tools, metrics, and shared terminology, which hampers the evaluation of adaptation effectiveness and the cost of inaction [30]. Moreover, failure to communicate uncertainty effectively undermines public awareness and trust, limiting political support [31,50,67].

Flexibility—as the ability to adapt processes, procedures, and regulatory frameworks—is central to climate-responsive spatial planning. However, flexibility cannot be considered in isolation; it must be understood in relation to inherent complexity and uncertainty [30,68,69], creating tension between adaptive responsiveness and the need for stable, robust governance. It is essential to recognize that these factors are deeply embedded within spatial planning systems, which are shaped by their socio-economic, political, and cultural contexts [40]. The interplay between the framework elements is summarized in

Table 1. Connections between the supportive factors of complexity, uncertainty and flexibility to fulfill the planning goals for demand for agility, robustness and legal certainty within the components of the planning theory.

Dimensions of the Planning Theory	Supportive Factors	Pillars for Climate-Resilient Spatial Planning
		Agility	Robustness	Legal Certainty
Substantive planning	Handling Complexity	Take advantage of the governance, policy, and financial frameworks to support adaptive actions, while avoiding redundancies.	Understanding socio-ecological complexity under climate change, recognizing interdependence between human and natural systems. It requires theoretical knowledge and a systemic evaluation of the urban and territorial systems to inform robust planning decisions.	Understanding territorial governance: structures and public administration competencies that integrate climate considerations into planning and mechanisms that support collaborative dialog, shared problem-solving, and inclusive deliberation.
Contextual planning	Embracing Uncertainty	Continuous monitoring and transparent communication of uncertainties.	Relying on science-based data and advanced planning tools for better informed and effective decision-making with transparency, legitimacy, and openness.	Clear planning criteria and rules to support effective planning and solid legal guarantees for security and public safety, long-term reliability, and legal accountability.
Procedural planning	Allowing Flexibility	Adaptability of structures, processes, and procedures.	Social justice and effective implementation mechanisms.	Regulatory flexibility without compromising legal integrity.

.

The differentiated analysis of the resulting nine interconnected areas enabled a deeper evaluation of the feasibility of achieving climate resilience through spatial planning and the capacity of statutory planning instruments to meet demands for agility, robustness, and legal certainty [63] in the face of urgent climate action.

3. Materials and Methods

This research employed a mixed-methods three-phased qualitative approach. A synthesis of the process can be seen in Figure 2.

3.1. Targeted Multivocal Literature Review

First, a targeted multivocal literature review was conducted to synthesize peer-reviewed articles, policy documents, and the gray literature (e.g., statutory municipal plans) in a semi-systematic manner. Our target was to assess the core literature on the theoretical foundations, not to systematically review all of the related research studies. The literature selection was guided by a combination of automated search in Scopus and author-led snowballing (i.e., iterative identification of relevant sources through reference chaining). The search utilized targeted keywords combinations and Boolean operators. The keywords included the following: (“spatial planning” OR “urban planning” OR “land use planning” OR “planning instruments”) AND (“climate change” OR “climate adaptation”) AND (“adaptive planning” OR “mainstreaming” OR “climate proofing” OR “gap” OR “implementation”). The inclusion criteria comprised studies that included the following factors to ensure that this review captured contemporary perspectives and challenges in the field and prioritized European case studies and methodological rigor: (1) a focus on the subareas of environmental science and social science; (2) a focus on urban contexts in Europe; (3) explicit discussions of the implementation of climate adaptation; (4) published in English or Spanish; (5) mainly published after 2010, except for the key literature. Content analysis of the selected literature facilitated the identification of the core hypotheses and recurring principles influencing adaptive planning approaches—particularly around complexity, uncertainty, and flexibility—which informed the development of the BRIDGE theoretical framework.

3.2. BRIDGE Indicator-Based Screening Tool

In the second phase, building on the literature review and the BRIDGE framework (Figure 1), a deductive approach was applied to create an indicator-based screening tool that operationalized it, ensuring structured, theory-driven investigation.

The BRIDGE screening tool consists of 27 indicators, evenly distributed across three interconnected factors of the theoretical framework. Complexity sets the foundational architecture (institutions, mandates, finance, territorial intelligence). Legal mandates (C.1_E) reinforce the legal basis; strategic coherence (C.2_E) creates direction; mainstreamed finance (C.3_E) provides fuel. Sound territorial intelligence (C.4_A–C.6_A) feeds those mandates with evidence. Clear governance arrangements (C.7_A–C.9_E) lock the whole package into an enforceable, cooperative structure. Uncertainty installs a learning operating system (data, scenarios, monitoring, rules that absorb new knowledge). Continuous monitoring (U.1_E) feeds back into the scientific toolbox (U.4_E–U.6_E). Clarified responsibilities (U.3_E) ensure that somebody acts on the new findings; the learning is then hardened into explicit criteria (U.7_A–U.9_A), stabilizing the legal environment without freezing it. Flexibility makes the machinery to adapt swiftly, changing course with minimal friction in response to emerging information, technologies, or social needs, dealing with the procedures, social safeguards, and adaptive regulations. Streamlined procedures (F.1_E) would be risky without guard-rails on justice and trade-offs (F.4_A–F.6_A). Adaptive regulations (F.8_A) give legal teeth to revisions triggered by new data (F.3_E). Scaling mechanisms (F.9_E) keep one-off pilots from stagnating.

Each indicator was assessed using qualitative, closed-ended, multiple-choice questions. Responses were converted to a standardized scale from 0 to 1, with four levels, 0, 0.25, 0.5, and 1, reflecting varying degrees of compliance, from complete absence to optimal implementation. This scoring method was based on the literature review and documented success cases. To enable cross-domain and cross-case comparison, a normalization process was applied, allowing for the consistent interpretation of the results and ensuring that each indicator contributed proportionally to the overall assessment. The maximum score per city is 27. If information was unavailable, the indicator was disabled and the score was distributed among the other indicators in the same domain.

Table 2. Indicator-based screening tool for assessing the ability of statutory urban plans to enable climate adaptation implementation across three core pillars—handling complexity, embracing uncertainty, and allowing for flexibility—organized by their contribution to agility, robustness, and legal certainty. Indicator ID codes: Prefix: C = complexity, U = uncertainty, F = flexibility; Number: group-related indicators; Suffix: E = enabling factor, A = anchoring factor.

Resilient and Climate Proof Spatial Planning Pillars and Supportive Factors	Indicators	Scoring	References
		Handling COMPLEXITY
Policy and financial frameworks Support agility	C1_E. Existence of legal mandates requiring integration of climate change considerations into spatial planning.	1p—There is a national and/or regional climate change law in place with provisions for mainstreaming climate considerations into formal planning instruments. 0.5p—There is no national or regional climate law, or it does exist, but does not steer mainstreaming. 0.25p—Voluntary action and political mandate guides actions, but is not legally enforceable in relation to mainstreaming climate adaptation into spatial planning instruments. 0p—Not defined.	[34,70]
	C2_E. Strategic alignment and degree of coherence between climate goals and sectoral/urban policies.	1p—Urban planning strategies and laws show clear and explicit alignment with climate goals (e.g., long-term political commitment (e.g., City Accord) to overcome short-term political cycles). 0.5p—There is some degree of alignment, but it is partial, general, or not fully integrated. 0.25p—Climate goals are mentioned in relation to planning, but without clear connection or actionable measures. 0p—No alignment between urban planning and climate goals is defined.	[29,30,34,43,71]
	C3_E. Degree to which climate risk reduction, adaptation, and resilience funding is integrated into standard urban planning and infrastructure budgets (mainstreamed vs. project-based financing).	1p—The plan secures funding and channels investment or blended finance for climate resilience, using at least two instruments (e.g., procurement, market-based tools, PPPs, financial or risk instruments, or supra-municipal funding). 0.5p—The plan recognizes a mix of instruments, but they are ad hoc or sporadic. 0.25p—Instruments are mentioned, but without clear strategy or connection to funding for resilience. 0p—No financial instruments are recognized in the plan.	[72,73,74]
Evaluation of the socio-ecological system under climate change Supports robustness	C4_A. Strategic long-term vision that harmonizes demographic trends, urban development, and economic growth, considering climate change impacts.	1p—The plan presents a long-term, systemic vision that goes beyond land use. It considers climate change scenarios, future demographic and socio-economic trends and developments that could influence climate risks. It aligns mitigation and adaptation actions, while also addressing co-benefits and avoiding maladaptation. 0.5p—The plan partially considers future land use and scenarios, but does not fully integrate climate perspective. 0.25p—Future scenarios or land use changes are mentioned—qualitative approach—but integration is minimal or unclear. 0p—The plan does not address long-term vision.	[34,65]
	C5_A. Presence and depth of climate change related vulnerability and risk assessments to inform planning decisions.	1p—The plan includes detailed, spatial risk mapping for multiple hazards, assessing exposure, vulnerability, and impacts on people, nature, and infrastructure across climate scenarios and timeframes, to guide priorities and urban planning. 0.5p—The plan includes spatially explicit climate change risk mapping for some relevant hazards and does inform urban development criteria. 0.25p—The plan includes non-spatially explicit climate change risk mapping for limited number of hazards and does not inform urban development criteria. 0p—The plan does not include climate risk mapping.	[1,7,55,56,62,63,64,75,76]
	C6_A. Identification and spatial mapping of potential areas for resilience interventions and nature-positive development.	1p—The plan maps and evaluates natural capital and ecosystem services on public and private lands, identifies areas for climate mitigation, risk reduction, and biodiversity enhancement to guide urban development and defines binding development parameters that support urban greenery. 0.5p—The plan analyses natural areas to some extent and specify binding development parameters supporting urban greenery not explicitly related to climate action. 0.25p—Natural areas are mentioned, but without clear evaluation or strong links to climate or development guidance. 0p –The plan does not address blue/green infrastructure, natural capital, or ecosystem services.	[7,15,41,57,58,59,60,61,77]
Territorial governance Supports legal certainty	C7_A. Coherence and subsidiarity in planning, with established mechanisms for coordination between regional and local governance levels (vertical mainstreaming).	1p—There is a legal framework that regulates the coherence from regional to local (or national to local where applicable). 0.5p—There is no legal framework, but the plan follows regional guidelines, or other informal mechanisms guarantee coherence (i.e., strategies) on how to consider climate adaptation into planning so that territorial decisions have a certain coherence, while applying subsidiarity principle on climate adaptation. 0p—Cascade planning perspective not applied.	[39,55,78,79]
	C8_A. Existence and functionality of multi-sectoral mechanism for inter-departmental coordination (horizontal mainstreaming) and active comprehensive stakeholder’s engagement for participatory planning and decision-making.	1p—The plan relies on a network governance model—collaborative, multisector, polycentric governance, adaptive governance, adaptive co-management. 0.5p—The plan relies on traditional public administration—hierarchical governance—with strong interdepartmental coordination (e.g., dedicated multi-actor institution/board or advisory body focused on climate change), and very strong participatory planning and budgeting (e.g., the plan allows for informal collaboration with strategic foresight either societal resilience model—co-management, civic ecology practices, self-governance/grassroots initiatives—and/or involves stakeholders with climate resilience implementation influence and capacity in the decisions. Public–private model: public–private partnership (PPP), non-state market-driven governance (NSMD), business–NGO partnerships, Sustainable Local Enterprise Networks (SLEN)). 0.25p—The plan relies on traditional public administration—hierarchical governance—with week interdepartmental coordination, but strong participatory planning and budgeting. 0p—The plan relies on traditional rigid public administration—hierarchical governance, closed governance—without participatory planning and budgeting meeting the minimum stakeholder engagement requirements set by law.	[39,43,57,71,78,79,80,81,82]
	C9_E. Recognition of arrangement with private stakeholders to bridge property rights and resilience.	1p—The plan recognizes and/or allow for agreements with potentially climate-affected individuals or organizations (e.g., voluntary, long-term agreements that restrict development while compensating landowners for stewardship, transfer of development fights allowing for landowners in high-risk zones to sell their development potential to areas better able to accommodate growth). 0.5p—Partial or informal recognition, but not clearly embedded in the plan. 0.25p—The plan allows for these agreements, but not clearly stated in the plan. 0p—The plan does not recognize nor allow.	[77,83,84]
		Embracing UNCERTAINTY
Monitoring and transparent communication of uncertainties Supports agility	U1_E. Presence of formal Monitoring and Evaluation frameworks with feedback loops for adaptation and improvement.	1p—The plan includes an on-going, regular process for the monitoring and evaluation of spatial and urban planning progress over time, tracking progress towards resilience goals, accountability of government with regard to climate adaptation, so the plan can be adjusted as needed in response to changing climate (monitoring, evaluation, reporting and learning (MERL). 0.5p—Monitoring system exists through the Strategic Environmental Assessment and to some extent indicators on climate change related impacts are included. 0.25p—Monitoring system exists, but not including indicators on climate change. 0p—The plan does not include a monitoring system.	[29,30,43,58]
	U2_E. Transparent and explicit communication of climate uncertainties and risk assumptions in planning documents.	1p—The plan includes communication of uncertainties in their mechanism for communication and awareness campaigns to improve decision-making. 0.5p—The plan is promoted in open access, and it is publicly available and clear communication about planning decisions on climate change exists, to foster trust and stakeholder engagement. 0.25p—The plan is publicly available, but does not specifically inform about uncertainties of climate change. 0p—The plan is not publicly available.	[50,56]
	U3_E. Clear assignment of roles, and responsibilities for climate action implementation.	1p—The plan identifies roles and responsibilities for the implementation of the climate resilience efforts across administration sectors and their competences. 0.5p—To some extent. 0.25p—Not clearly formulated. 0p—Not defined.	[29,30,43,71,85]
Science-based data and supporting methodologies, resources and capacities Supports robustness	U4_E. Ensuring the sound use of multi- and transdisciplinary knowledge, comprehensive science-based data, and information in planning decisions.	1p—The plan relies on current scientific evidence and the best available data and projections on climate challenges, optimizing resources (e.g., knowledge platforms, spatial data, digital twins) to integrate regularly updated climate information. The plan systematically assesses and documents the reliability, consistency, and confidence levels of the data and evidence used for climate-related decision-making. 0.5p—Climate data and information are generated on demand for targeted planning purposes (i.e., development plan). The plan partially addresses the reliability or consistency of the data, but the assessment is limited, not comprehensive. 0.25p—Climate data and information is used, but not accessible and/or outdated and/or not integrated in city platforms or spatial data infrastructures. The plan mentions data sources, but does not assess or communicate reliability, consistency, or uncertainties in a meaningful way. 0p—No assessment or documentation of data reliability, consistency, or uncertainties is provided.	[12,86,87]
	U5_E. Use of advanced scenario-based planning approach to inform planning decisions.	1p—Decision-makers and stakeholders evaluate adaptation scenarios, highlight options and actions, and the plan includes a comparative analysis of planning, alternatives across different scenarios (i.e., IPCC SSP4.5/SSP8.5) and time horizons (2040, 2070, 2100), assessing potential outcomes. 0.5p—The plan does not include comparative analysis of alternatives, but uses conventional, linear, and probabilistic approaches for risk assessment. 0.25p—Scenarios or risks are mentioned, but without structured evaluation or exploration of alternatives. 0p –No evaluation of adaptation scenarios or planning alternatives.	[1,7,12,13,15,32,41,55,56,65,86,87,88,89,90]
	U6_E. Extent to which innovative, method-based, and technological tools are used to support climate-resilient planning.	1p—The plan clearly and comprehensively applies innovative, method-based, and technological tools such as decision-support systems, foresight methods, evaluation frameworks, and consensus-building strategies. It addresses multi-sectoral and multi-scale conflicts of interest; various climate scenarios and temporal scales; spatial demand for adaptation; trade-offs with mitigation (maladaptation risks). 0.5p—The plan applies some elements of these tools and methods, but the application is either limited in scope, detail, or effectiveness, or addresses some, but not all, of the challenges listed above. 0.25p—The plan mentions or references some tools or methods but with minimal detail or unclear application. There is no strong evidence of structured or innovative use. 0p—The plan does not apply any relevant innovative methods or technological tools or fails to address any of the listed aspects.	[7,15,65,88,91]
Planning criteria and rules Supports legal certainty	U7_A. Definition of clear, measurable, and enforceable climate-related policy criteria and targets.	1p—The plan sets specific criteria and targets for climate resilience clearly within its objectives and aspirations. 0.5p—Climate resilience is addressed in a generic way, with some references to criteria or targets but without specificity. 0.25p—Climate resilience is mentioned, but without clear criteria or targets. 0p—The plan does not address climate resilience criteria or targets.	[68]
	U8_A. Provisions—guidelines or requirements—for climate-proof, resilient, and nature-based urbanization and building design in urban development codes.	1p—The plan includes specific rules, standards, and guidelines associated with climate change to inform climate proof and nature positive urbanization and building design for subsidiary development planning within the framework of structural development planning. 0.5p—The plan provides generic technical recommendations, typically found in annexes, but lacking enforceable or detailed standards. 0,25p—Climate considerations are mentioned, but without clear application to subsidiary planning or actionable detail. 0p—No climate-related rules, standards, or recommendations are included.	[8,92]
	U9_A. Extent to which territorial climate justice spatial disparities in climate risks and adaptation capacity is considered.	1p—The plan detects territorial unbalances and defines compensation mechanisms to ensure planning decisions promote spatial justice—secured and equitable access to resources and services—and climate justice recognition and support for vulnerable areas and populations. 0.5p—Spatial and climate justice are identified, but not fully promoted by the planning outcomes. 0.25p—Unbalances are mentioned, but neither detailed nor linked to equity measures. 0p—No detection of territorial unbalances or consideration of equity.	[1,7,55,56,83,93,94]
		Allowing FLEXIBILITY
Design, elaboration and approval processes, and procedures Supports agility	F1_E. Streamlined, simplified, and accelerated planning processes that integrate climate considerations and approval procedures.	1p—Procedures for spatial and urban plan approval are streamlined, and structures/processes are easily adaptable to unexpected emerging changes. 0.5p—Procedures are somewhat streamlined and adaptable, but not consistently or fully. 0.25p—Some recognition of adaptability, but implementation is limited or unclear. 0p—Procedures are not streamlined, and adaptability to changes is absent.	[7,90,95,96]
	F2_E. Alignment of urban planning instruments with existing strategic energy and climate action plans.	1p—The plan builds on and/or aligns with a dedicated local climate plan (e.g., Sustainable Energy and Climate Action Plan) and uses a spatially explicit approach. 0.5p—The plan aligns with a local climate plan, but the approach is not spatially explicit. 0.25p—The plan mentions climate goals, but no real alignment or spatial link is established. 0p—No alignment with a local climate plan.	[34,39]
	F3_E. Adaptability and capacity to revise and update planning instruments in response to new climate information.	1p—The plan demonstrates clear proactivity, applying the precautionary principle and self-limiting strategies to address environmental or climate risks, even without a formal mandate or legal obligation. 0.5p—The plan includes regulatory or ordinance-based updates that improve planning practices, such as the following: Sustainable Urban Drainage Systems (SUDS); Green roofs and facades; Ground floor use regulations in flood-prone areas; Structural modification criteria (e.g., allowing for water flow or enhancing thermal comfort). These demonstrate planning improvements, but do not reflect self-limitation beyond legal requirements. 0.25p—The plan mentions or suggests such measures, but implementation is unclear, limited in scope, or not supported by specific examples. 0p—The plan does not apply any proactive, precautionary, or updated regulatory measures.	[55,97,98,99]
Social justice and effective implementation mechanisms Supports robustness	F4_A. Prioritization, combination and structured timeline for implementation of climate actions.	1p—The plan prioritizes actions and defines an implementation sequence to allow for incremental resource allocation, addressing both extreme events and progressive climate changes. 0.5p—The plan partially prioritizes actions or hints at sequencing, but lacks full clarity or integration across climate risks. 0.25p—Action prioritization or sequencing is mentioned vaguely, with no structured link to climate urgency. 0p—No prioritization of actions or sequencing for climate resilience is defined.	[1,12,100]
	F5_A. Extent to which marginalized groups are actively engaged in planning processes and equitably benefit from climate-resilient, socially just development outcomes.	1p—The plan fully guarantees a just transition in social terms by systematically including climate-vulnerable groups (e.g., elderly, low-income communities, those at risk of energy poverty) across all diagnosis, vulnerability, and risk assessments. It also demonstrates sensitivity to different social vulnerabilities within urban planning processes. 0.5p—The plan partially addresses a just transition by identifying climate-vulnerable groups in some assessments or urban planning elements, but does not consistently integrate or prioritize their needs across all stages. 0.25p—The plan briefly acknowledges vulnerable groups or social aspects of climate risks, but there is little evidence of their systematic inclusion in assessments or urban planning decisions. 0p—The plan does not address social vulnerability, climate-vulnerable groups, or the concept of a just transition.	[77,83,84,93,94,101,102]
	F6_A. Explicit identification and management of potential synergies and trade-offs between climate mitigation and adaptation/resilience approaches.	1p—The plan clearly integrates mitigation and adaptation, identifies co-benefits, synergies, and addresses maladaptation risks. 0.5p—The plan includes both mitigation and adaptation efforts, but does not clearly articulate their synergies, trade-offs, or maladaptation concerns. 0.25p—The plan mentions both themes, but linkages are vague or only implied. 0p—The plan does not address adaptation or resilience at all.	[1,8,24,103]
Regulatory nature Supports legal certainty	F7_A. Regulatory nature of the planning tools that support the implementation of climate resilience.	1p—There are not hard zoning regulations. For instance, the plan does have land use regulations for structural planning and applies Performance-Based Zoning: setting resilience performance criteria (e.g., flood-storage capacity, green-cover minimums) rather than prescriptive use rules, enabling flexibility for detailed planning (e.g., does not grant land use rights). Action-based and incentive-based tools can be used to support implementation of climate-resilient actions. 0.5 p—The plan does have enforcement and regulatory tools, while allowing for adjustments to land use allocations, infrastructure priorities, and regulatory measures without requiring a complete overhaul of the planning framework, e.g., declassification of urban areas on unconsolidated urban land based on risk and vulnerability assessments. 0.25p—The plan does have enforcement and regulatory tools that imply hard zoning regulations that mandate and prohibit specific urban forms and uses. 0p—The plan does not have enforcement and regulatory tools, either action-based or incentive-based tools that may be used to include climate resilience provisions on property rights in areas at potential risk, but rather information-based tools (e.g., guidelines).	[29,68,104]
	F8_A. Existence of regulatory frameworks allowing for flexible adaptation to emerging climate risks (adaptive regulation).	1p—The plan implements a cyclical approach, policies are periodically reviewed, refined, and updated based on monitoring and feedback. This implies mechanisms for temporary regulations, conditional permits, or transitional land use arrangements. 0.5p–To some extent less than 10 years. 0.25p—Vey lengthy cycles > 10 years. 0p—None or more than 20 years.	[34,105,106,107]
	F9_E. Evidence of successful upscaling of intervention-oriented research-focused pilot projects addressing climate resilience.	1p—The plan is informed and guided by the scalability of pilot and innovative projects, using research initiatives, local regulatory sandboxes, living labs, or similar mechanisms. 0.5p—The plan mentions pilot or innovative projects, but application to planning is limited or not systematically integrated. 0.25p—Pilot projects or innovation are mentioned vaguely, without clear influence on the plan. 0p—No reference to pilot projects, research initiatives, or innovation mechanisms.	[67,102,108,109,110]

provides an overview of the indicators and the associated metrics within each. The supportive factors within complexity, uncertainty, and flexibility were divided into the following: enabling factors referring to conditions or resources that facilitate or accelerate the implementation of climate-resilient spatial planning, focusing on capacity, incentives, coordination, and adaptability (marked with an E in the legend); and anchoring factors referring to the structural or normative elements that stabilize, institutionalize, and legitimize climate-resilient spatial planning, providing continuity, legal backing, and long-term reliability (marked with an A in the legend).

The Supplementary Materials provide the complete list of indicators, along with descriptions of the planning components that define the criteria of a climate-proof plan, the scoring methods used, and the justification for considering each indicator, as supported by the literature.

3.3. Case Studies

Finally, the indicator-based screening tool was tested by analyzing the statutory urban planning instruments in six European cities, each introduced in

Table 3. Outline of selected case studies and statutory plans analyzed.

City	Population Estimated in 2025	Biogeographic Regions [114]	Climate Risks Faced Based on European Climate Risk Assessment (EUCRA) [111]	Planning Family and Governance Model [40,112,113]	Statutory Plan Analyzed
Bilbao	346,746	Lusitanian coastal Southern Atlantic climate; warm summers, mild wet winters; heathlands and Pyrenean oak forests	Extreme heat and heatwaves Coastal and river flooding (Nerbioi basin) Health impacts Infrastructure vulnerability	Urbanism tradition/regionalized unitary, with features of comprehensive integrated approach	Urban General Development Plan (PGOU) February adopted in 2023
Mannheim	347,710	Continental warm summers, cold winters; beech forests and temperate woodlands	River flooding (Rhine basin) Heatwaves Water stress Seasonal droughts Infrastructure vulnerability	Comprehensive integrated approach/federal states	Model Spatial Organization (MRO) the city’s integrated spatial urban development concept in review in 2024
Liverpool	928,997	Atlantic North Oceanic humid climate; moderate temperatures; deciduous forests and coastal ecosystems	Coastal and urban flooding Storm surges Health risks (damp housing, heat) Ecosystem degradation	British land use management/decentralized unitary Focus on regulation of land use; discretionary decision-making; planning as development control	Liverpool Local Plan 2013–2033 adopted in 2022
Warsaw	1,800,230	Continental cold winters, warm summers; central European lowlands with mixed forests	Heatwaves River and flash flooding Agricultural disruption Air quality deterioration	Decentralized unitary with strong local and regional level; often influenced by EU policies	General Zoning Plan adopted in 2024
Vienna	2,005,500	Continental cold winters, warm summers; central European lowlands Alpine influence; mixed forest ecosystems	Heat stress Water scarcity (Alpine snowpack) Flooding (Danube) Biodiversity loss	Central regional economic planning: management of regional economy by public interventions into infrastructure and development/federal states	Urban Development Plan (STEP) adopted in 2025
Paris	11,346,800	Atlantic Central temperate climate; mild winters, warm summers; Atlantic-influenced	Urban heatwaves Flooding (Seine) Infrastructure vulnerability Social inequality impacts	Regional economic planning/classic unitary countryless emphasis on local discretion	Le Plan Local d’Urbanisme de Paris (PLU) adopted in 2024

Population estimated in 2025.

. These cities were chosen to represent geographic diversity, the climate zones and risks faced [111], and the distinct planning traditions and governance structures as identified in [40,112,113]. These were also selected considering their climate adaptation leadership, data availability, and their documented actions on climate-sensitive plans. The primary purpose of these case studies was to serve as a pilot for the BRIDGE screening tool and test its applicability to different contexts. The assessment was initially conducted by two authors and was validated by external stakeholders at the city level, except for Warsaw and Liverpool, where validation was not carried out.

A qualitative comparative analysis was then undertaken between the selected cities, allowing us to extract recommendations that scaled-up to other urban realities.

4. Results

4.1. Key Findings: City Scores

The six pilot-tested cities show strong initial commitments, but uneven capacities to institutionalize climate adaptation into statutory instruments. Comprehensive results, including the metrics and implementation index scores of the referenced documents assessed (sourced from official city websites), are provided in the Supplementary Materials.

Vienna (19.75 points) sets a benchmark with a broad portfolio of binding tools, flexible features, and social justice integration. Vienna leads in climate adaptation through the STEP 2035, a long-term urban development plan aiming at a climate-friendly, socially equitable, and resilient city by 2035. Despite Austria’s lack of national climate law, Vienna has pioneered a comprehensive approach with their Climate Strategy, Wiener Klimabudget, and Climate Check system. The STEP 2035 integrates adaptation into core urban design principles—green infrastructure, sustainable mobility, and energy efficiency—through policies like green roofs and facade greening. Vienna was one of the first cities to implement a comprehensive climate protection program (KLIP), starting in 1999. The plan is supported by satellite imagery. The city uses climate scenarios, heat vulnerability maps, and cooling corridor strategies to guide targeted interventions. Institutional coordination is strong, with the Division for Climate and Vienna Climate Council providing oversight. Citizen participation is embedded through initiatives like Vienna Climate Teams and a citizens’ jury, with the Garden Streets and micro-parks exemplifying participatory design. However, the STEP 2035 lacks a sequential action plan and clear implementation roles. While climate adaptation criteria are in building codes, private developers often lack incentives, and the city relies on voluntary mechanisms like the Green Pass, which is positively seen as contributing to flexibility. Although the city conducts regular monitoring, it lacks a centralized system for tracking resilience and informing planning in a dynamic way. Vienna STEP2035 could improve its ability to enable the implementation of adaptation by mapping and clarifying roles and risk ownership, deepen climate scenarios, consider and communicate uncertainties, and establish a stable centralized MERL system.

Paris (17.75 points) follows, excelling in mainstreaming and adaptive regulation, but is still weak in monitoring and distributing responsibilities. Paris is at the forefront of climate resilience, operating under the French Energy and Climate Law (2019) and 2023 National Strategy for Energy and Climate, which prioritize carbon neutrality. The city has developed the Bioclimatic Local Urban Plan (PLUb), set to be revised by 2024, which integrates adaptation into spatial planning. The PLUb sets ambitious targets—40% of the city’s surface area to be permeable and vegetated by 2050, 100% energy renovation by 2050, and 40% public housing by 2035—with 30% designated as social housing. It uses “hard zoning” regulations and a “positive externalities” requirement, mandating that new construction exceeds environmental standards in at least three of the nine established criteria to obtain a permit. Paris leverages data-driven planning through the Paris Urbanism Agency (Apur), which conducts comprehensive territorial diagnoses and uses granular vulnerability maps for heat stress and flooding. The plan integrates social equity into climate adaptation through affordable housing (aiming for 40% public housing by 2035, with at least 30% being social housing), environmental health (requiring the greening of buildings, open spaces, and reduced impervious surfaces to combat urban heat islands, benefiting vulnerable groups lacking air conditioning or living in dense areas), and inclusive governance (via neighborhood councils, youth forums, and thematic workshops). While the plan includes general equity measures, more targeted actions for specific vulnerable groups would strengthen its impact. The city engages citizens through the Citizens’ Assembly (2020) and promotes social equity by prioritizing interventions in high-risk areas. There is a public report by the City of Paris called “Paris à 50 degrés” (a 50 degrees Paris) that provides a scenario of the impacts and projections, demonstrating the aim of communicating uncertainties. However, the PLUb lacks a sequential action plan, and responsibilities for climate action are not clearly defined. The city lacks a centralized MERL system, and the communication of uncertainty in climate projections could be improved. Bureaucratic processes could delay implementation. The Paris PLUb could improve its ability to enable the implementation of adaptation by strengthen monitoring with a stable centralized MERL system, in line with the city Climate Plan 2024–2030.

Mannheim (13.25 points) employs a structured, multi-level planning framework, with the Model Spatial Order (MRO), Land Use Plan (FNP), and Development Plans (Bebauungspläne) ensuring coherence between long-term vision and implementation. The instrument assessed in this research has been the MRO. The city’s Climate Protection Program 2030 and Climate Protection Action Plan integrate adaptation into planning, supported by data tools like Climate View and heat stress mapping. The city engages citizens through workshops, roundtables, and a permanent Participation Advisory Board, although participation remains voluntary and lacks long-term commitment. Despite a EUR 10 million climate fund and access to EU and state funding, budgeting prioritizes CO₂ savings, with climate-related damages and long-term costs often remaining unaccounted for. A biodiversity strategy is under development, but adaptation is not formally integrated into legally binding instruments. The Concept Adaptation to Climate Change in Mannheim aims to strengthen resilience, but the lack of a sequential action plan and weak interdepartmental coordination limit progress. Mannheim could improve its ability to enable the implementation of adaptation by enhancing the integration of adaptation into legal frameworks, securing long-term budgeting, overcoming yearly budgets, and fostering cross-sectoral collaboration.

Bilbao (12 points) aligns with national and regional climate laws, including Spain’s Climate Change and Energy Transition Law 7/2021 and the Basque Country’s Energy Transition and Climate Change Law 1/2024, which mandate climate considerations in planning. The city’s Urban General Development Plan (PGOU) and Metropolitan Territorial Plan (PTP) embed climate resilience, supported by climate data and vulnerability assessments focused on flooding, heat stress (including heat waves), and extreme precipitation. However, the integration of future climate scenarios and trade-offs between mitigation and adaptation remains limited. The Sustainable Energy and Climate Action Plan (SECAP), published in 2024, supports adaptation, but is not fully embedded in planning. A lack of a dedicated climate governance body leads to fragmented coordination, while rigid land use regulations hinder flexible, climate-responsive adjustments. In any case, the city has the potential to deploy ordinances ad hoc for climate adaptation, which offers flexibility. Despite pilot projects like RESIN and RAMSES, implementation is constrained by lengthy approval processes and the absence of a sequential action plan. Bilbao PGOU could improve its ability to enable the implementation of adaptation by stronger cross-sectoral coordination, better data integration and a dynamic long term MERL system, and regulatory reforms to increase flexibility.

Warsaw (8.75 points) lacks national climate law, but relies on the National Energy and Climate Plan 2021–2030 and National Environmental Policy 2030, both emphasizing carbon neutrality. The General Zoning Plan analyzed in this study responds to new legislation that requires municipalities to adopt this strategic instrument for sustainable development. Warsaw is involved in the C40 Cities network, signaling political commitment, but no coherent long-term resilience strategy exists. The General Zoning Plan (GZP) includes binding parameters like the minimum proportion of biologically active areas, reflecting a focus on green infrastructure. However, it lacks climate risk analysis, future scenarios, and spatial integration of adaptation measures, remaining biased toward mitigation. While the KLIMADA project (2017–2022) developed climate scenarios and educational tools, their systematic use in planning is unconfirmed. The Climate Protection Team at City Hall focuses on carbon reduction, with limited interdepartmental coordination. Public engagement includes Million Trees and public consultations, but strategic communication on climate risks is underdeveloped. The city accesses EU and provincial funding, but lacks a dedicated instrument for climate resilience. The lack of a sequential action plan and unclear implementation of resilience provisions hinder progress. Warsaw GZP could improve its ability to enable the implementation of adaptation by incorporating climate scenarios for evidence-based planning decisions, clarifying the roles and responsibilities in adaptation, and develop a comprehensive adaptation strategy and a MERL system.

Liverpool (7.5 points) operates under the UK’s Climate Change Act (2008), which mandates net-zero emissions by 2050 and a national adaptation program. However, the National Planning Policy Framework (NPPF) does not require mainstreaming of climate risks into spatial planning, creating a disconnect between national goals and local implementation. The city’s Local Plan (2013–2033) includes policies on flood risk and green infrastructure, but it is unclear whether climate change projections and future scenarios are considered. Flood risk mapping it is understood based on the available information accessed, which does not account for climate change, undermining its long-term relevance. While the city has adopted mandatory Sustainable Drainage Systems (SuDS) and benefits from the Liverpool City Region (LCR) Spatial Development Strategy, there is no record of a city-wide climate action accord or a sequential implementation plan. The URBAN GreenUP project (EUR 4.5 m) supports green infrastructure, but it seems that the incorporation of climate adaptation into the statutory plan remains underdeveloped compared to mitigation. Despite a 2019 climate emergency declaration, hard zoning regulations, insufficient consideration of climate change projects to evaluate climate-related hazards, and governance may hinder effective adaptation. The Liverpool Local Plan 2041 could improve its ability to enable the implementation of adaptation, but must embed climate scenarios into planning, clarify responsibilities and risk ownership, and strengthen monitoring frameworks. Please note that the Local Plan 2041 is in the consultation phase at the time of this research, and our limited access to the Local Plan 2013–2033 may have underestimated the city’s actual capacity to support climate change adaptation.

4.2. Qualitative Comparative Analysis Across Cities

Across the six cities, the three highest and three lowest scoring are as follows (

Table 4. Top three and bottom three indicators by six-city average. E = enabler, A = anchoring. Maximum aggregated (indicator) score is 6.

Indicator	Score
F9_E Evidence of successful upscaling of intervention-oriented research-focused pilot projects addressing climate resilience	6
C1_E Existence of legal mandates requiring integration of climate change considerations into spatial planning	5
F2_E Alignment of urban planning instruments with existing strategic energy and climate action plans	4.75
F4_A Prioritization, combination, and structured timeline for implementation of climate actions	1.25
U3_E Clear assignment of roles and responsibilities for climate action implementation	1
U5_E Use of advanced scenario-based planning approach to inform planning decisions	1

).

The highest averages are for foundational elements as legal mandates for climate mainstreaming into planning (C1_E), existing climate adaptation plans and strategies (F2_E), and up-scalability of climate adaptation demonstrators (F9_E). These are critical first steps toward long-term planning. On the other hand, the lowest-scoring indicators are related to cities’ limited-timeline development for the implementation of climate actions (F4_A), use of advanced scenario-based planning (U5_E), or clear risk ownership (U3_E), reflecting a limited capacity for the long-term institutionalization of resilience.

Uncertainty, analyzed using nine indicators (U1–U9), emerges as the most unevenly addressed dimension. All cities score poorly for communication of uncertainty (U2_E). The monitoring and evaluation indicator (U1_E) is weak across the board, with no formal adaptive learning systems in all cities, except Vienna. Sound use of multi- and transdisciplinary knowledge, comprehensive science-based data and information in planning decisions (U4_E), and the use of innovative, method-based, and technological tools to support climate-resilient planning (U6_E) also score very low. These findings reveal that, while cities may recognize that the future is uncertain, they are not yet plan for it structurally—a critical shortfall in the face of accelerating and unpredictable climate impacts. Figure 3 presents the distribution of the scores across the indicators for the six cities.

Figure 4 highlights the performance and balance between agility, robustness, and legal certainty (A), between complexity, uncertainty, and flexibility, (B) and presents a summary of the results across cities. A composite index was constructed for each of the three pillars—agility, robustness, and legal certainty—as well as for the supporting factors—complexity, uncertainty, and flexibility—by summing the metric scores across relevant indicators. Each foundation and factor could achieve a maximum score of nine points.

5. Discussion

Our findings reveal significant potential in statutory urban planning instruments as key enablers for overcoming the persistent implementation gap in climate adaptation, a challenge widely acknowledged by scholars and policymakers [18,54,115,116], despite long-standing criticism about its effectiveness in Europe [12,45,117]. The results of this study demonstrate that these instruments can be systematically evaluated and strengthened to better translate climate policy into resilient urban outcomes.

The indicator-based BRIDGE screening tool developed in this study provides a practical, structured, and theory-driven tool for assessing the climate resilience potential of statutory urban plans. By operationalizing the core dimensions of complexity, uncertainty, and flexibility, the matrix enables a systematic evaluation of how planning systems address the demands of agility, robustness, and legal certainty in the face of climate change. This tool is not merely a diagnostic instrument, but also a practical mechanism for practitioners and policymakers to identify systemic gaps, prioritize interventions, and initiate evidence-based discussions of adaptation challenges. The BRIDGE framework and screening tool reinforces Wamsler 2022 [19], particularly supporting the system level strategies III Organizational (managerial, regulatory, and intra-organizational), IV Internal mainstreaming, and V Inter-organizational mainstreaming for risk governance.

Moreover, the screening tool’s dual focus on enabling (E) and anchoring (A) factors—reflecting capacity-building and institutional stability—offers a nuanced understanding of climate-resilient planning. It reveals that effective adaptation not only requires a flexible, adaptive processes (e.g., streamlined procedures, adaptive regulation), but also stable, legally grounded frameworks (e.g., clear criteria, enforceable rules). The tool therefore bridges the gap between theoretical concepts and practical implementation, helping cities to move beyond reactive measures toward systemic, long-term resilience.

The results underscore that statutory planning instruments are not inherently ineffective, but that their potential is often unrealized due to systemic barriers such as rigid procedures, fragmented governance, and a lack of integrated monitoring. The screening tool provides a way to diagnose these barriers and design targeted interventions.

While the BRIDGE screening tool does not introduce entirely new concepts or groundbreaking innovations, compared to existing climate mainstreaming approaches (i.e., ref. [19]), it offers a simplified, targeted model for cities and practitioners to assess statutory plans, identify areas for improvement, and initiate discussions of the root causes of adaptation challenges. Its innovation lies in focusing on the key factors of statutory planning that are most relevant to climate adaptation, providing a structured way to evaluate how effectively plans translate policy into on-the-ground action. This enables practitioners to identify critical areas for improvement and assess the overall capacity of planning systems to support adaptation.

Across all of the six cities, scenario thinking, dynamic monitoring, and true considerations of uncertainty remain embryonic, in line with the literature [65]. Despite all cities using risk diagnostics for major hazards, a review of the available information indicates static evaluations, with limited monitoring and evaluations of how risk could be reduced based on adaptation measures and their effectiveness. Traditional risk models fall short under high uncertainty; instead, flexible scenario-based approaches help to identify trade-offs and synergies (e.g., afforestation with non-native species may lead to maladaptation) [38,89]. Integrating diverse climate scenarios (emissions scenarios and time horizons) early in planning improves climate-proofing across scales, while addressing future trends enhances resilience [1,7,118]. Assessing vulnerability and comparing scenario-based alternatives strengthens decision-making and reduces risk [1,56,119].

Genuine participatory planning also appears to be limited, although all cities demonstrate the mechanisms and potential to implement it. Vienna and Paris explicitly consider social equity for climate adaptation. It is worth mentioning that the PLUB includes social equity through affordable housing (aiming for 40% public housing by 2035, with at least 30% as social housing), environmental health (requiring greening of buildings, open spaces, and reduced impervious surfaces to combat urban heat islands, benefiting vulnerable groups lacking air conditioning or living in dense areas), and inclusive governance (via neighborhood councils, youth forums, and thematic workshops). While the plan includes general equity measures, more targeted actions for specific vulnerable groups would strengthen its impact.

The plans analyzed, despite having features that offer some flexibility (e.g., strategic character of the MRO in Mannheim, potential for deploying ordinances in Bilbao and Liverpool, Vienna’s STEP 2038 voluntary mechanisms like the Green Pass, prioritization of actions, and sequence of implementation for incremental resource use (e.g., garden streets, micro-parks, priority transformation areas, reuse of existing buildings), and Paris’s PLUb ensuring regular updates of climate data in urban planning in line with the six-year-revised Paris Climate Plan), lack an adaptation-specific Monitoring, Evaluation, Research, and Learning (MERL) system, which undermines the credibility of actual adaptation and true adaptive regulation.

All of the cities generally perform better on enablers: these include political leadership, stakeholder participation, and access to data. Anchoring indicators—such as climate integration into legal codes, budgets, or land use regulation—tend to score lower. This suggests that most cities have built momentum and established good foundations, but lack the institutional guarantees to make resilience permanent, in line with [29,34,35]. Insufficient financing for climate adaptation measures limits municipal action. To ensure adaptation, a binding government commitment to increase general financial resources would therefore be necessary.

All of the cities navigate between the regulatory and strategic planning approaches that have shaped European planning since the mid-20th century [36]. While flexibility supports adaptive responses, spatial planning must also ensure legal certainty to maintain coherence, predictability, and legitimacy in decision-making [68]. The distinction between statutory regulatory plans and strategic plans is particularly relevant for climate adaptation [12,36]. Regulatory plans offer legal certainty and enforceability, protecting property rights and providing predictable rules, but often rely on rigid, outdated structures that hinder climate responsiveness [12,34,45]. In contrast, strategic plans are more flexible and participatory, enabling broader stakeholder engagement and future-oriented adaptation. However, their lack of legal enforceability creates uncertainty, especially in urban contexts where land rights are institutionalized. Without this, flexibility may be coopted by market forces, undermining public control and long-term resilience [12,34,45]. Bureaucratic rigidity continues to reinforce outdated practices, impeding effective climate adaptation.

5.1. Emergent Planning Dilemmas

The application of the BRIDGE framework through the indicator-based screening tool to the case study cities highlights the tensions between flexibility, complexity, and uncertainty, which allows for a deeper discussion of the capacity to fulfill the demand for agility, robustness, and legal certainty in the pilot statutory plans. These tensions derived in emergent planning dilemmas faced by local actors in implementing effective adaptation. These dilemmas collectively challenge formal urban planning by forcing an optimal balance between addressing complexity towards robust decisions, stability to offer solid legal guarantees, and adaptability to manage climate risks and future uncertainties, ensuring effective action. This highlights the importance of the development of robust long-term spatial plans that provide legal certainty to investors and the public about “what can be built”, while not responding to climate resilience demands in an agile way to adjust policies as conditions change in response to the urgency of climate action. The pilot cities provided examples of these dilemmas.

5.1.1. The Agility Conflict: Dilemma Between Handling Complexity (Substantive Planning) and Allowing for Flexibility (Procedural Planning)

This dilemma highlights the tension between addressing complex substantive issues and the need for rapid but robust decision-making. It would be beneficial that spatial planning relies on flexible, adaptive methods that respond to emerging patterns, rather than forcing fixed solutions. Our findings reveal that flexibility still remains a major challenge: only Vienna and Paris demonstrate clear mechanisms for updating plans or responding to new climate data. For instance, in Vienna, the STEP 2035 prioritizes actions and defines implementation sequences so that resources can be allocated incrementally in some areas (e.g., garden streets (Gartenstraßen), micro-parks (Beserlparks), priority areas for transformation (prioritäre Gebiete für Transformation)) and are given priority to utilize existing building infrastructures (bestehende Gebäude weiter nutzen). In Paris PLUb is closely aligned with the Paris Climate Plan, which undergoes revisions every six years to ensure that updates in climate data and projections are systematically incorporated into urban planning strategies.

This creates a paradox: plans can be well-thought-out and stable, but also inflexible, which may reduce effectiveness in dynamic climate contexts. Traditional top-down approaches have been seen to be insufficient due to the intricate nature of climate risks and their interactions with socio-political systems [65,120]. Particularly in recent years, spatial planning in the EU has evolved broadening their public function scope, away from the traditional emphasis solely on land use planning [41]. It has been recognized as a mechanism that aids in reducing risks such as flooding, sea-level rise, heat stress, droughts, wildfires, landslides, and other natural hazards associated with climate change [54,111,115,116].

The limitations of institutional capacity and resources to cope with the inherent complexity of climate change issues [35,81]—and, moreover, the gap between actual climate adaptation, needs, and available knowledge, skills, and accessible and usable data—is also a key factor that impairs planning processes [88]. Path dependency, inertia of policy cycles, reliance on traditional models, and resistance to change [65] limit innovation and forward-thinking and lead to a policy lag whereby new objectives are slow to emerge [61,121]. In addition, it is difficult to act in private land because of a lack of flexibility, i.e., Bilbao, Manheim, and Warsaw. Although most European planning and governance frameworks have well-established arrangements for democratic accountability, they are not always geared toward targeting the most vulnerable sectors of society or ensuring that engagement is collaborative as opposed to merely informative [122]. Deficient engagement processes limit the legitimacy of planning decisions, particularly for involving vulnerable communities [43,61], which may lead to the resistance of climate action, i.e., Bilbao and Warsaw.

5.1.2. The Robustness Conflict: Dilemma Between Handling Complexity (Substantive Planning) and Embracing Uncertainty (Contextual Planning)

This dilemma arises from the need to make robust decisions in the face of multiple uncertainties. The challenge here lies in acknowledging the uncertainties for increasing the robustness of planning decisions and, therefore, increasing legal security over land use rights. In recent years, in the context of adaptive planning, there has been an increase in spatially specific climate and adaptation knowledge, including the development of scenarios for adaptation to climate change and the monitoring of them [123]. This work reveals that all of the analyzed cities do show some short of scientific evidence on climate vulnerability and risk that helps promote robust decision-making, but the consideration of uncertainty is missing in all of the cities: there are no formal systems to track and revise adaptation progress under climate change scenarios (see U.1_E). Funding and regulatory backing remain limited, leaving plans vulnerable to political or financial shifts. Planning for uncertainty is underdeveloped: all of the cities seem to treat risk as static rather than dynamic. Uncertainty is inherent to planning process, that must deal with environmental related to physical, economic, or social conditions, with climate change serving as an additional factor that intensifies these uncertainties, which can compromise the robustness of planning decisions [1,11].

Our findings align with the literature, which identifies the failure to raise public awareness about the tangible impacts of climate change [67] and the effective communication of uncertainty [50] as key challenges. These shortcomings can undermine public trust and weaken political support for climate adaptation measures. None of the analyzed cities show a systematic communication of uncertainty. Lack of knowledge on how to communicate effective support of decision-making is being recognized in the literature as well. This challenge could be overcome by the use of climate services by tailoring messages to specific users, using risk-based language, and employing visualizations like probability maps, which, in recent years, are being increasingly developed and utilized to support climate change adaptation efforts [1]. These services offer comprehensive knowledge and customized tools to assess climate-related risks, inform the design of adaptation strategies, and foster resilience across various planning scales [86]. For climate services to be effective, it is important that developers address the inherent uncertainties of climate change, collaborate closely with end-users to create high-quality and practical solutions, build trust, and enhance users’ capacities to adapt to climate change challenges [87]. In this context, informal instruments, including community initiatives for public participation, provide unique benefits for advancing local climate adaptation through enhanced engagement and local empowerment [124].

Misalignment between complexity and uncertainty is recognized in our findings. Unlike mitigation efforts, which include clear greenhouse emissions-reduction guidelines, climate change adaptation lacks a robust regulatory framework and universal measure to evaluate the effectiveness of adaptation measures comprehensively across different scenarios and timeframes [1,9]. Internal uncertainties in relation to climate change relate to the choice of climate models, socio-economic, and emissions scenarios and time projections [125], as well as the quality and validity of the data used [56]. The lack of standardized terminology, method-based tools, metrics, and standards for evaluating climate change scenarios and the impacts of adaptation options makes it difficult not only to address the climate risks across different scenarios [65,78], but also to evaluate the adaptation costs and effectiveness, including the costs of inaction, leading to an underestimation of adaptation’s importance in planning decisions and limiting the actual implementation of adaptation measures [30].

5.1.3. The Legal Certainty Conflict: Dilemma Between Embracing Uncertainty (Contextual Planning) and Allowing for Flexibility (Procedural Planning)

Flexibility cannot be considered in isolation; it must be understood in relation to the inherent complexity and uncertainty of planning, creating a tension between adaptive responsiveness and the need for stable, robust governance. This reflects the dilemma of balancing science-based, evidence-driven regulations with the flexibility required to respond to uncertain climate-impact trajectories. Rigid plans enhance procedural certainty and may provide clear rules that promote transparency and trust, but can lead to slow decision-making and therefore hinder the implementation of climate-resilient measures [34,60,68]. The lack of legal recognition leaves vulnerable groups without protection or support, highlighting the need for tenure security and inclusive governance [34].

Outdated, inflexible, and ineffective legal structures, institutions, and processes fail to regulate the emerging challenges and adopt and/or adapt current policies, regulations, and rules to changing circumstances [50,68]. Bureaucratic rigidity reinforces outdated practices and hinders the adoption of climate adaptation [126]. In addition, strong private property rights may hinder climate-resilient land use policies, like zoning changes or retreat strategies, due to resistance from property owners, i.e., Bilbao, Manheim, and Warsaw.

Urban planning authorities, although not always in control of large public works budgets, influence development through land use decisions that enable value capture and guide growth. By regulating urbanization in high-risk areas like floodplains, they promote patterns aligned with natural processes, reducing impacts and enhancing resilience [12]. Legal innovations—such as voluntary agreements, development rights transfers, or performance-based zoning—combined with monitoring and adaptive planning, can align property rights with resilient land use [55]. The case of Liverpool could explain the low rate of screening, since most information on voluntary agreements and strategic projects might not be available and have not been included in the evaluation. In Spain, for instance, in regions such as the Basque Country (País Vasco), Navarra, Madrid, and the Canary Islands, land use planning reforms are ongoing and aim to promote flexibility [34]. To simplify administrative procedures, some regions—such as Valencia—have introduced regulatory reforms, including Decree-Law 7/2024, which establishes an administrative simplification framework [127]. This law streamlines the procedures for investments and productive activities, reduces red tape, and fosters a shift in administrative culture.

5.2. Planning Decline in Europe as an Opportunity

The decline of planning and criticisms of planning effectiveness in Europe are being argued by several scholars [40,65]. Key concerns supported by our study include reduced investment, rigid legal structures and planning regulations, declining participation in planning activities, and the erosion of planning capacity and expertise [12,40,45,60,113]. This crisis of spatial planning may constitute an opportunity for a paradigm shift towards adaptive and climate-resilient approaches [12]. Furthermore, current discussions continue to explore the relationship between regulatory and strategic planning approaches, which have influenced European planning systems since the mid-20th century [36]. These debates have increasingly called for a hybrid approach [12,34,65] that integrates regulatory frameworks and strategic adaptive planning strategies to strengthen climate resilience, as exemplified by the MRO in Mannheim and the PLUB in Paris. Their adoption depends on the planning system’s objectives, and effective coordination of both approaches is essential [60]. All of these criticisms and reflections may drive spatial planning toward a blended approach of strategic and regulatory roles, guiding policies on the one hand and assigning land uses and structures on the other, creating normative models while maintaining strategic flexibility. Recent European spatial planning reforms have increasingly shifted towards flexible, market-driven, and collaborative approaches, moving away from rigid, top-down public-sector-led planning [40]. This evolution has led to the development of smart, comprehensive spatial planning that integrates economic, social, and environmental concerns and emphasizes the management, monitoring, and evaluation of planning outcomes [12,68]. However, the operationalization of flexibility remains a key challenge, particularly due to tensions between robustness and adaptability in planning governance and the legal complexities surrounding land use rights [34,68]. This issue is particularly relevant in Bilbao, involving multiple layers—from national to regional and local levels—with various competent authorities responsible for addressing coastal flooding.

5.3. Implications for Policy and Practice

Based on the configuration of the theoretical framework itself and the empirical findings observed in the case studies, the following recommendations are proposed for practitioners and policymakers:

• Adopt a hybrid planning approach that integrates context-specific and regulatory frameworks oriented toward problem solving, with strategic adaptive planning vision at the regional/supra municipal level.
• Ensure the legal anchoring and enforcement of climate resilience from a precautionary principle by embedding risk management into zoning, building codes, and development permits.
• Institutionalize monitoring and learning by establishing formal mechanisms for the continuous evaluation of hazards, exposure, and vulnerabilities, as well as the effectiveness of adaptation actions, enabling iterative adjustments based on performance data and emerging evidence.
• Plan for uncertainty using scenario-based planning, transparent communication of assumptions, and the development of contingency measures. Given the potential for transformational change—particularly in coastal zones—planners, using the precautionary principle, should anticipate shifts in land use that may necessitate measures such as managed retreat, land acquisition, or expropriation. These actions carry significant social and economic implications and must be proactively planned and socially negotiated.
• Enhance agility by simplifying and streamlining planning processes and empowering local departments to respond swiftly to changing risks. Improve material flexibility by, for example, enabling temporary land use to accommodate short-term needs during extreme events.
• Secure long-term funding with a dedicated budget allocation for resilience actions, moving beyond project-based financing to ensure sustained investment.

5.4. Potential Streams of Climate-Resilient Planning Based on Balancing Agility, Robustness and Legal Certainty

The possible streams of climate-resilient spatial planning based on balancing agility (the ability to respond quickly to changing climate conditions), robustness (ensuring decisions hold under uncertainty), and legal certainty (clear, enforceable rules and procedures) are summarized in Figure 5. Agility-focused planning emphasizes flexibility and rapid response, often through informal or strategic plans, but may lack legal enforceability. Robustness-oriented planning prioritizes long-term stability and risk reduction, using evidence-based scenarios, but can be slow to adapt. Legal-certainty-driven planning ensures compliance, accountability, and institutional stability, but may struggle to keep pace with urgent climate needs.

6. Conclusions

This study contributes to the climate adaptation field by proving practical insights into the factors that can help to close the adaptation implementation gap. The BRIDGE framework and indicator-based matrix serve as a screening tool to guide policymakers in aligning land use planning instruments with EU climate goals, particularly in regions with fragmented governance. By identifying where indicators cluster or lag, stakeholders can prioritize actions such as strengthening regulations, enhancing data systems, streamlining procedures, establishing long term MERL systems or reinforcing participatory mechanisms. The BRIDGE screening tool’s adaptability across diverse European planning systems demonstrates its potential as a scalable diagnostic instrument. Testing the tool across a broader range of cities and planning systems is essential to validate its applicability and scalability. A key strength of this study lies in the BRIDGE framework’s ability to systematically screen and compare formal planning instruments across cities. Its operational matrix enables objective, comparable assessments based on publicly available documents, following established methodologies.

However, several limitations must be acknowledged. This study relies on document analysis, which is a valid method for assessing policy intent, but does not rely on on-the-ground implementation realities such as enforcement, stakeholder engagement, or political constraints. This approach may introduce bias, as it reflects formal policy design rather than actual practice. While it identifies broad, general factors, these encompass a wide range of context- and actor-specific details that vary significantly across settings. To deepen our understanding of adaptation implementation, future research should integrate document analysis with qualitative methods—such as interviews, stakeholder consultations, and field observations—thereby assessing implementation fidelity and identifying the gaps between policy intent and practice. This would require a systematic explanation and understanding of the root causes of the gap to define ways to reduce, remove, or strategically manage it.

This study’s application of the framework is qualitative and interpretive, limiting the potential for standardized comparison. There is a need for more quantitative or standardized metrics and stronger scoring methods to enhance comparability across cases. Additionally, the sample of six cities, while diverse, does not fully represent the breadth of European planning systems, and generalizability must be approached with caution. International comparisons are further complicated by the diversity of national legal orders, socio-economic conditions, and climatic contexts across Europe.

Addressing uncertainty remains a central challenge in climate-proof planning. To better understand why adaptation is progressing more slowly than the growing urgency of climate change, we need deeper insights into how different decision-makers perceive uncertainty. Approaches like scenario-based thinking and adaptation pathways offer promising tools for anticipating risks, enabling real-time adaptation, and seizing emerging opportunities. Deeper insights into the enabling factors—such as governance mechanisms, legal instruments, and procedural innovations—would help decision-makers design more effective and adaptive planning systems.