The study “Innovation drivers in climate adaptation” by Melina Matos examines how climate adaptation planning evolved in 230 US cities between 2011 and 2021. Drawing on innovation theory, it identifies the factors that lead cities not only to begin adaptation work but also to advance it. The results reveal a critical disconnect: the drivers that prompt cities to start adapting differ markedly from those that lead them to develop and publish formal adaptation plans.
The findings underline how complex adaptation is. Cities need to invest not only in administrative capacity and resources, but also in motivation, learning networks, and a clear understanding of how public officials and residents perceive the need for action.
By 2021, 98 of the 230 cities (42.61%) had published at least one plan addressing climate adaptation, either standalone or integrated into a broader plan, marking the shift from informal discussion to policy formulation. By 2011, 128 cities (55.65%) had already begun adaptation activities.
Binary logistic regression showed that public officials’ perception of rising climate hazards was a strong driver of initial action. Each additional hazard identified increased a city’s odds of initiating adaptation by 14%. Access to external funding and previous adaptation experience were also powerful predictors, increasing the odds by 270% and 272% respectively.
Moving on to publish a plan, by contrast, depended more on residents’ perception of climate risk and sustained participation in learning networks. Each one-percentage-point increase in the share of residents who believed climate change would moderately or greatly harm the US raised the odds of a city publishing a plan by 15%. Cities that remained ICLEI members throughout 2011–2021 had 144% higher odds of developing an adaptation plan. Motivation-related factors, such as leadership commitment, were significant only for starting adaptation, not for advancing it.
The geographical distribution reveals marked disparities. California led, with 53 cities in the 2011 survey and 30 of them (56.6%) publishing adaptation plans by 2021. New York followed, with 13 of 23 cities (56.5%) reaching the planning stage, then Massachusetts with 7 of 12 (58.3%) and Florida with 5 of 10 (50%).
Other states lagged far behind. Of the 45 states represented, Mississippi, North Dakota, South Dakota and West Virginia each had only one or two cities in the survey, and none had published a plan by 2021.
In the US, climate adaptation began as a grassroots movement led by local governments, often without federal guidance. Early efforts focused on identifying vulnerabilities and opening discussions, but progress from awareness to formal planning has been slow.
Climate adaptation fits within the broader field of urban innovation: new policy domains that respond to emerging urban challenges. The literature identifies four drivers of innovation: perceived need, motivation, learning networks, and resources. The study applies this framework to explain why different factors shape the initiation and the advancement of adaptation.
The study also introduces a new two-stage perspective, mapping climate adaptation onto Rogers’ innovation-decision model and the public policy process. The first stage, agenda-setting, involves recognizing the need to adapt. The second, policy formulation, involves drafting actionable plans. Separating the two stages gives a more nuanced understanding of urban policy innovation and shows why interventions need to be tailored to each.
This longitudinal study draws on the 2011 MIT-ICLEI survey of climate adaptation planning in 230 US cities across 45 states. To track the cities’ progress over a decade, the author supplemented the survey with secondary sources, including the US Census, FEMA’s National Risk Index, the Yale Climate Opinion Maps, and local government documents. Cities were then assessed on whether they had published a standalone or integrated adaptation plan by December 2021.
Binary logistic regression models tested the significance of 17 independent variables grouped under the four innovation drivers. Model 1 examined the factors behind initiating adaptation, based on the 2011 survey responses. Model 2 examined the factors behind advancement, measured by plans published by 2021.
No variable was significant in both models, which shows that starting adaptation and sustaining policy development are driven by distinct forces. Officials’ perception of risk and access to external funding trigger initiation, while public awareness and long-term participation in networks support advancement.
