**1. Introduction**

Urban areas are complex, vulnerable and continuously evolving systems. In these dynamic areas, the existence of interacting strategic services and of interdependent services and assets, as well as the involvement of a multiplicity of stakeholders, adds complexity to their management. Besides, the significant impacts of climate dynamics (such as intense precipitation events, tidal effects, droughts or heat waves) in the urban strategic services, people, natural environment and economy, as well as the aggravation of current conditions and the emergence of new hazards, also need to be considered in their management [1,2].

As referred to in [3], following the World Economic Forum 2014, by 2050, exposure of city dwellers to various hazards, including earthquakes, tsunamis, urban floods, cyclones and storm surges, is expected to double. These challenges require an integrated and forward-looking approach to resilient and sustainable urban development, incorporating the interdependencies between systems as well as including stakeholders and citizens perceptions and needs. In order to achieve this, several long-term agendas have been adopted as parts of the United Nations Agenda 2030 for Sustainable Development, such as the Sendai Framework for Disaster Risk Reduction 2015–2030, the Sustainable Development Goals, the New Urban Agenda and the Paris Agreement [3]. A relevant consideration in all of these agendas is the incorporation of assessment steps for tracking their implementation [4].

The resilience concept has evolved over time and among disciplines [5,6]. Herein, urban resilience refers to the ability of human settlements to withstand, recover quickly and adapt from any plausible hazards. Resilience to disruptive events not only refers to reducing risks and damage from disasters, but also the ability to quickly bounce back to a stable state. Besides addressing disaster risk reduction, resilience includes changes in circumstances [7–10].

In order to identify the real needs for enhancing urban resilience, as well as the efficiency and effectiveness of planned or implemented measures, a resilience assessment is essential. Therefore, assessing the current and expected future status of resilience is a basis for cities to know where they are, helping to identify strengths and weaknesses, thus supporting the decision on strategies, actions and measures to be taken, planning for the long-, medium- and short-terms and assessing the progress.

Since the cities are dynamic systems with evolving hazards, it is essential to regularly carry out the assessment of their resilience, considering the principle of continuous improvement [11], and to have tools to support this. Several tools and frameworks for assessing resilience have been developed in different fields of study by a wide variety of stakeholders, such as those created by Local Governments for Sustainability (ICLEI) 2010, UN-Habitat City Resilience Profiling Tool (UN-Habitat CRPT) 2013, Rockefeller and Arup 2014, World Bank 2015, United Nations Office for Disaster Risk Reduction (UNDRR, former UNISDR) 2017, U.S. Environmental Protection Agency (EPA) 2017, among others [5,7–9,12–16]. Within the scope of the current work, i.e., climate change with a focus on water, relevant resilience assessment frameworks are presented in Table 1. It synthetizes the themes, urban sectors and metrics considered in each framework [5,7,13,16,17].


**Table 1.** Synthesis of resilience assessment frameworks for climate change.


**Table 1.** *Cont.*

\* e.g., Telecommunications, healthcare, education, population.

Taking into account the mentioned scope, the need of a framework (Table 1) that is freely available to be usable by cities and urban services managers was identified, allowing, on the one hand, a structured and objective-driven assessment of their city's resilience considering the integration of all themes and sectors simultaneously and, on the other hand, an assessment of resilience of a single sector considering its interdependencies with other sectors and its contribution to the city resilience.

Grounded in the analysis of these existing frameworks, and in order to bridge the additional gaps and needs identified, particularly in the assessment of strategic urban sectors and their interactions with both other sectors and in the wider urban system, the Resilience Assessment Framework (RAF) was developed—a resilience assessment framework with focus on climate change and the water cycle, herein described.
