What is Resilience? - Definitions

"A resilient city can adapt to a variety of changing conditions and withstand shocks while still providing essential services to its residents.”
-World Bank

Resilience is the ability to withstand and recover quickly from any plausible shock and stress, and maintain continuity of services.

Resilience is the capacity of individuals, communities and systems to survive, adapt, and grow in the face of stress and shocks, and even transform when conditions require it.
-The Rockefeller Foundation

"Urban Resilience is the capacity of individuals, communities, institutions, businesses and systems within a city to survive, adapt and thrive no matter what kinds of chronic stresses or acute shocks they encounter.
-100 Resilient Cities - Pioneered by the Rockefeller Foundation

The ability of a system to respond successfully to climate variability and climate change.”
-Intergovernmental Panel on Climate Change (IPCC)

“The ability of a system, community or society exposed to hazards to resist, absorb, accommodate, adapt to, transform and recover from the effects of a hazard in a timely and efficient manner, including through the preservation and restoration of its essential basic structures and functions through risk management.”
-United Nations Office for Disaster Risk Reduction (UNISDR)


General Terminology

(Rockefeller Foundation, 100 Resilient Cities, UN-Habitat, UNISDR, 100 Resilient Cities and C40 Cities Climate Leadership Group)

City Resilience Framework - developed by Arup with support from The Rockefeller Foundation, the City Resilience Framework (CRF) provides a lens to understand the complexity of cities and the drivers that contribute to their resilience. Evidence-based, the CRF provides common understanding of what constitutes a resilient city and a common language that enables cities to share knowledge and experiences.

City Resilience Index - is built on the CRF. Like the CRF, it is a holistic articulation of city resilience structured around 4 dimensions, 12 indicators that essentially tell us what matters most when a city faces chronic stresses or sudden shocks. The CRI also includes 58 sub-indicators that add further definition and identify the critical factors that contribute to the resilience of urban systems. The sub-indicators also integrate the 7 qualities of resilient systems that research shows are so critically important: Integrated, inclusive, flexible, redundant, reflective, resourceful, and robust. The foundation of measurement for the CRI is a set of 156 prompt questions (3 per sub-indicator) with qualitative and quantitative fields.

Chief Resilience Officer – a “CRO” is a senior level advisor to the mayor, who leads and coordinates the city’s resilience building efforts on a day to day basis.

Resilience Assets – the physical, economic, social, built and natural resources that contribute to a city’s resilience.

Resilience Dividend - a range of net positive benefits—from cost savings and cost avoidance to better outcomes for vulnerable populations—that result from integrated decision making. AND/OR when discrete interventions achieve multiple benefits across multiple systems as a result of applying a Resilience Lens in planning and project development and prioritizing decisions that will deliver resilience value.

Resilience Lens – an analytical framework to evaluate options and ensure city actions achieve multiple positive outcomes while mitigating negative consequences.

Resilience Strategy – a tactical roadmap to build resilience in the city. The strategy articulates the city’s resilience priorities and specific initiatives for short-, medium-, and long-term implementation.

Resilience Value Realization – a structured process for identifying and delivering the resilience value-creating opportunities present in projects. Includes initial Resilience Opportunity Framing workshop and later Resilience Value Reviews. A way to increase likelihood a project or strategy will yield a Resilience Dividend.

Risk – a function of the likelihood/probability of a shock or stress combined with the consequence of the shock or stress.

Sector – distinct parts of society, in particular private, public, civil-society.

Silo – can be a verb: to isolate systems, processes, departments, etc. from others. Or a noun, to indicate an isolated and separate entity, process, or system.

Shock – an acute natural or human-made event or phenomenon threatening major loss of life, damage to assets and a city’s ability to function and provide basic services, particularly for poor or vulnerable populations.

Stress – a chronic (ongoing or cyclical) natural or human-made event or phenomenon that renders the city less able to function and provide basic services, particularly for poor or vulnerable populations. 


Qualities of Resilience

(Rockefeller Foundation/Arup)

Flexible - Flexibility implies that systems can change, evolve and adapt in response to changing circumstances. This may favor decentralized and modular approaches to infrastructure or ecosystem management. Flexibility can be achieved through the introduction of new knowledge and technologies, as needed. It also means considering and incorporating indigenous or traditional knowledge and practices in new ways.

Inclusive - Inclusion emphasizes the need for broad consultation and engagement of communities, including the most vulnerable groups. Addressing the shocks or stresses faced by one sector, location, or community in isolation of others is an anathema to the notion of resilience. An inclusive approach contributes to a sense of shared ownership or a joint vision to build city resilience.

Integrated - Integration and alignment between city systems promotes consistency in decision-making and ensures that all investments are mutually supportive to a common outcome. Integration is evident within and between resilient systems, and across different scales of their operation. Exchange of information between systems enables them to function collectively and respond rapidly through shorter feedback loops throughout the city.

Redundant - Redundancy refers to spare capacity purposely created within systems so that they can accommodate disruption, extreme pressures or surges in demand. It includes diversity: the presence of multiple ways to achieve a given need or full a particular function. Examples include distributed infrastructure networks and resource reserves. Redundancies should be intentional, cost-effective and prioritized at a city-wide scale, and should not be an externality of inefficient design.

Reflective - Reflective systems are accepting of the inherent and ever-increasing uncertainty and change in today’s world. They have mechanisms to continuously evolve, and will modify standards or norms based on emerging evidence, rather than seeking permanent solutions based on the status quo. As a result, people and institutions examine and systematically learn from their past experiences, and leverage this learning to inform future decision-making.

Resourceful - Resourcefulness implies that people and institutions are able to rapidly find different ways to achieve their goals or meet their needs during a shock or when under stress. This may include investing in capacity to anticipate future conditions, set priorities, and respond, for example, by mobilizing and coordinating wider human, financial and physical resources. Resourcefulness is instrumental to a city’s ability to restore functionality of critical systems, potentially under severely constrained conditions.

Robust - Robust systems include well-conceived, constructed and managed physical assets, so that they can withstand the impacts of hazard events without significant damage or loss of function. Robust design anticipates potential failures in systems, making provision to ensure failure is predictable, safe, and not disproportionate to the cause. Over-reliance on a single asset, cascading failure and design thresholds that might lead to catastrophic collapse if exceeded are actively avoided.