The core argument is deceptively simple. Conventional evaluation frameworks treat urban nature-based solutions as collections of measurable assets—a square meter of green roof, a cubic meter of stormwater retention, a degree Celsius of cooling—and then ask whether these assets deliver expected ecosystem services. This asset-based logic fits neatly into cost-benefit analyses, engineering performance metrics, and municipal reporting cycles. But it systematically obscures the relational dimensions of adaptation: who participates in designing and maintaining green infrastructure, how communities attach meaning to restored landscapes, how knowledge flows between residents and planners, and how institutional trust shapes whether interventions are sustained beyond pilot phases. Relationality, in this framing, is not a soft supplement to hard metrics but a constitutive property of urban socio-ecological systems.

Technically, the paper draws on insights from relational ontology and socio-ecological systems theory, fields that view entities not as discrete objects with fixed attributes but as nodes defined by their connections and interactions. In a relational view, a bioswale is not merely soil, vegetation, and drainage capacity; it is an artifact produced through municipal procurement rules, community stewardship agreements, hydrological dynamics, and the ecological history of the site. Evaluating only the physical performance of the bioswale captures a fraction of its adaptive significance. The relational lens asks instead how the intervention reconfigures relationships—between the city and its water, between neighbors who co-maintain a rain garden, between planners and the communities whose neighborhoods are transformed.

This perspective has profound implications for how success is defined. Traditional indicators of nature-based solution performance—runoff reduction, biodiversity indices, temperature moderation—remain important, but they are incomplete. An evaluation framework centered on relationality would additionally assess the quality of participation in planning processes, the distribution of decision-making power, the strength of stewardship networks, and the degree to which interventions strengthen or erode place attachment and social cohesion. These relational outcomes are not incidental benefits; the authors argue they are often the mechanisms through which adaptive capacity is actually built. A city that greens a riverbank without engaging the surrounding community may achieve hydrological targets while leaving its adaptive capacity unchanged or even diminished.

The urgency of this argument reflects real-world patterns in urban adaptation practice. Across many cities, nature-based solutions have been criticized as vehicles of green gentrification, in which environmental improvements raise property values and displace the very residents who are most vulnerable to climate hazards. An asset-based evaluation would record a successful intervention: trees planted, heat island effect reduced, amenity value created. A relational evaluation would ask different questions: whose relationships to the neighborhood were disrupted, which communities gained or lost access to decision-making, and how institutional relationships between city agencies and low-income residents evolved through the process. Only the second framing reveals the equity dynamics that increasingly determine whether adaptation is just.

Relational evaluation also changes the temporal scope of assessment. Conventional metrics are typically measured at project completion or over short monitoring windows, reflecting funding cycles and political timelines. But relational processes—trust building, learning networks, the maturation of stewardship arrangements—unfold over years and decades. Urban forests, for example, accrue their cooling and carbon benefits slowly, and the social institutions that maintain them often take even longer to consolidate. The paper suggests that evaluation must become longitudinal and iterative, treating evaluation not as a terminal audit but as an ongoing dialogue that feeds learning back into governance. In this sense, relationality connects directly to adaptive management: the capacity of a city to learn from its interventions is itself a relational achievement.

Methodologically, the shift toward relationality demands a pluralistic toolkit. Quantitative indicators of social network structure, participation rates, and longitudinal wellbeing surveys can be combined with qualitative approaches—ethnography, participatory mapping, and community-based monitoring—that capture the texture of human-nature relationships. Co-production of evaluation criteria with affected communities is central: rather than importing evaluation frameworks designed by distant experts, relational evaluation begins with the question of whose values and knowledge count. This does not mean abandoning rigor; it means redefining rigor to include validity across multiple ways of knowing, from hydrological modeling to Indigenous and local ecological knowledge.

The implications extend to policy and finance. Global frameworks such as the Sendai Framework for Disaster Risk Reduction, the Paris Agreement’s adaptation goals, and the emerging biodiversity agenda all call for robust adaptation evaluation, yet most national reporting remains anchored in asset-based metrics. If relational outcomes were incorporated into adaptation finance criteria, funders could reward projects that build durable stewardship institutions and equitable governance, not merely those that deliver the cheapest cubic meter of retention. Municipal audit offices, development banks, and philanthropic funders all have leverage to institutionalize relational indicators, and the paper’s argument suggests that failing to do so creates a systematic blind spot in global adaptation accounting.

Ultimately, the argument is a call to recentrate the human and ecological bonds that make adaptation possible. Climate change is often described as a crisis of physics and chemistry, but its impacts and remedies are mediated through relationships: between cities and their watersheds, between institutions and residents, between present decisions and future generations. Urban nature-based solutions offer a rare opportunity to strengthen those relationships while delivering concrete climate benefits. Whether that opportunity is realized depends on whether evaluation evolves from a technical scorecard into a relational practice—one that sees green infrastructure not as a product to be verified, but as a living set of connections to be understood, nurtured, and sustained.

Subject of Research: Relational approaches to evaluating climate adaptation through urban nature-based solutions

Article Title: Relationality must be at the heart of climate adaptation evaluation: insights from urban nature-based solutions

Article References: Goodwin, S., Alda-Vidal, C., Amorim-Maia, A. T., Lewis, W., Loroño, M., & Olazabal, M. (2026). Relationality must be at the heart of climate adaptation evaluation: insights from urban nature-based solutions. npj Urban Sustainability. https://doi.org/10.1038/s42949-026-00460-8

Image Credits: AI Generated

DOI: 10.1038/s42949-026-00460-8

Keywords: climate adaptation, nature-based solutions, urban sustainability, relationality, evaluation frameworks, green infrastructure, socio-ecological systems, climate resilience, urban planning, adaptive governance, green gentrification, community stewardship