Keywords

1 Introduction

The world today is experiencing the largest shift from rural to urban areas in the history of settlements. Currently, the world population of 7.8 billion is expected to reach about 9.8 billion in 2050. With this increase in population, the share of humans living in the urban areas is also expected to increase up to 68% by 2050 (United Nations 2018).

While this process of urbanization is creating larger economic opportunities; it is also placing extraordinary stress on natural environment as well as the government institutions. Local authorities and state governments are finding it challenging to meet the demands of the ever-increasing population in cities, especially of the poor inhabitants. The authorities are unable to provide them with basic facilities of housing, sewerage, and water. Therefore, we see urban areas being more prone to social risks as well as natural disasters.

In many cities, the scale of the risks is much higher due to the quality of housing and infrastructure services (Huq et al. 2007). The rural inhabitants who migrate to urban areas seeking for better opportunities end up living in the riskiest zones of the city usually near riverbeds and steep slopes and are trapped into the condition of urban poverty. This increases the vulnerability of the people. The rapid scale of urbanization is leading to urban conflicts and social unrest. Widening inequalities, practice of unfair law and order, and weak urban governance are further escalating the intensity of social risk (Lehmann 2015). In regard to environmental hazards, landslides, catastrophic fires, and massive floods are all increasing at an alarming rate affecting huge parts of the cities. The increasing frequency of these natural disasters is being caused by human-induced activities. For instance, large scale deforestation and mining may cause landslides. Climate change is expected to further increase the frequency and intensity of adverse events in cities. Additionally, the recent pandemic demonstrated that cities could also be highly vulnerable to infectious diseases (Sharifi and Khavarian-Garmsir 2020).

Urban areas have seemed to form a direct relation between climate change and the process of urbanization (Filho et al. 2019). Climate change is leading to depletion in water supplies in cities, and water scarcity issues are further exacerbated due to high rates of evaporation and losses and excessive consumption. Cities are also affected by other climate-induced impacts such as extreme heat. This way, it is impacting the health of the citizens, more among the people residing in the informal settlements in developing and less developed countries.

The two continents of Africa and Asia are identified as regions most vulnerable to the impacts of climate change mostly due to rise in population growth rates and rapid increase in urban slums (Filho et al. 2019). Vulnerability and risks further increase in cities situated in flood plains and coastal areas. For instance, Dhaka, Mumbai, and Shanghai, considered as the largest cities of the world, are becoming more and more prone to floods and storms every year. Many cities from Africa, such as Lagos, Alexandria, and others are prone to higher risks from flooding and storms as well (Huq et al. 2007).

In certain urban regions of the world, there is increase in the frequency and intensity of flooding which might be due to high sea levels, glacial outbursts, and heavier or prolonged rainfall. In other cities, there is a reduction in the average rainfall which has even led to droughts. Hence, all these changing phenomena is likely to be caused due to climate change.

Reckien et al. (2017) state that “climate change is acknowledged as the largest threat to our societies in the coming decades.” The water quantity and quality are heavily being impacted and will continue to if significant amount of investment is not done for various interventions. (Huq et al. 2007). Change in urban temperature would continue to rise which is highly influenced by Urban Heat Island (UHI) effect. Furthermore, the climate change will increase the heat stress caused by UHI. This will lead to negative consequences to the ecosystem services as well as on the health of the citizens. (Emilsson and Sang 2017; Sharifi et al. 2021). The shift in temperatures and rainfall patterns, and intensified concentration of CO2 are projected to have adverse impacts on the ways species interact in an urban space and on the ecosystem services. Warmer urban temperatures will also be a breeding ground for mosquitoes, thus, spreading diseases like malaria and dengue fever (Huq et al. 2007). Climate change has the potential to multiply the effect on these existing stresses, which will expose the cities to more dangerous disasters and risks.

The impact of these risks caused due to the environmental degradation processes and gaps in urban governance structure are felt differently in cities across the world. Future catastrophes would be further exaggerated if right actions are not taken on time. There is a need to develop integrated solutions to address a complex range of vulnerabilities and risks in urban areas by building resilience in cities. Urban resilience doesn’t only look into preparing cities for responding to disasters or hazards but rather taking initiatives to prevent them from happening in the first place (Gonçalves 2018). Resilience in cities does not only account for natural hazards but also human conflicts, economic downturns, and governance failures. This makes it even more imperative for cities to be resilient. To achieve resilience an incredible coordination level between different actors in the city, such as government authorities, private institutes, and industries and, the community, is necessary (Gonçalves 2018). Thereafter, resilient cities can handle natural and human-induced disasters, protect the lives of their citizens, and promote well-being and sustainable growth of cities and its people.

This chapter aims to explain the origin of and underlying principles of the concept of resilience as a beneficial strategy for improved urban management. For this, it is essential to first understand the various concepts and characteristics that revolve around urban resilience. Therefore, this chapter is based on literature review about this field.

The remainder of this chapter has the following structure: Sect. 4.2 provides an overview of the historical background of resilience and the building of the concept of urban resilience. In Sect. 4.3, concepts and definitions of urban resilience have been reviewed. Section 4.4 elaborates the main dimensions and characteristics of urban resilience. Lastly, in Sect. 4.5, conclusions on the need for urban resilience are drawn.

2 Background and Historical Overview

The word “resilience” is believed to be derived from the Latin verb “resilire” which means to recoil or rebound. “Resilience” or “resiliency” became common terms during the second half of the seventeenth century for explaining any counteractions in physical aspects (Gößling-Reisemann et al. 2018). The concept first originated in the works of Thomas Tredgold from physics of material in the year 1818 (Iliuk and Teperik 2018). He used the words to explain the reason behind the ways certain types of wood could accommodate sudden and strong loads without breaking (Iliuk and Teperik 2018). Through this academic discipline, the concept of resilience was further introduced in English speaking countries (Gößling-Reisemann et al. 2018).

With the outgrowing popularity of the word “resilience,” there are different views and applications surrounding the concept. According to a study conducted by Iliuk and Teperik (2018), resilience has a long history across different fields of study. The infographic developed by them illustrates the evolution of the concept in various fields since 1950. The chartFootnote 1 explicitly shows that psychology has been in clear lead since the past 40 years, since the term is extensively used in relation to cognitive responses.

According to some scholars in psychology, resilience is considered as a personal trait (Garmezy 1971). According to Olsson et al. (2015), psychologists use the term resilience “to describe an individual’s reactions to potentially traumatic events.” Norman Garmezy, a clinical psychologist, is considered to be the founder of research in resilience. He defined resilience as being “not necessarily impervious to stress, rather, resilience is designed to reflect the capacity for recovery and maintained adaptive behaviour that may follow initial retreat or incapacity upon initiating a stressful event” (Shean 2015). Other scholars of psychology such as Michael Rutter, Emily Werner, Suniya Luther, and Michael Unger have also defined resilience according to their understanding and field of specialization (Shean 2015).

In ecology, the concept of resilience was introduced by C. S. Holling to express the persistence of an ecosystem going through a change due to natural or anthropogenic causes. Holling argued that the concept is applicable to more fields than just ecosystems but also, socio-ecological and economic systems (Thorén 2014). Ecological resilience will be discussed further in the remainder of this section.

2.1 Major Approaches to Resilience

With regards to an urban system, resilience thinking has three major approaches: (1) Engineering resilience (2) Ecological resilience (3) Socio-ecological resilience. These will be briefly discussed below.

Resilience from an engineering perspective is based on the ability to resist shocks and the speed of recovery of a system after going through a series of disturbances. The sooner the system recovers, the more resilient it is. However, this interpretation considers the system to be in a static state and so, this conceptualization of resilience emphasizes the speed and ability of the system to bounce back to its pre-disturbance stage (UN-Habitat 2017). The definition revolves around the measure of stability. Physics, control system design, and material engineering are some prominent fields which use this definition (Gunderson 2000).

Over time, ecological resilience became prominent in understanding the science and management of ecosystems when pushed beyond their limits for recovering from a situation that involved many stressors on the system (Falk et al. 2019). The term resilience was introduced into ecology by C. S. Holling in 1973. It was to help in understanding the dynamics observed in ecosystems and defined it as “the amount of disturbance that an ecosystem could withstand without changing self-organized processes and structures” (Gunderson 2000). Ecological resilience measures the magnitude of disturbance a system can absorb before “the system redefines its structure by changing the variables and processes that control behaviour” (Gunderson 2000).

The stark difference between engineering and ecological resilience lies in the equilibrium state. Engineering resilience considers only one stable or equilibrium state emphasizes staying within that state or returning to it in a timely manner. Whereas, ecological resilience presumes multiple states for a system and the ability of the system to transition between the states is considered to be important. Gunderson (2000) states some examples of the transition in ecological systems, such as grassland dominated terrain to woodland dominated terrain in Zimbabwe. The multiple states are described in the form of plantation and the stressor or disturbance is grazing.

From 1970s, many social scientists and urbanists started to believe that the social fabric of regions is intrinsically interwoven with the ecosystems they depend on. This conceptual thinking led to the emergence of concepts focused on socio-ecological systems. When resilience was embedded in this concept, it came to be known as socio-ecological resilience, which “incorporates the idea of adaptation, learning and self-organization in addition to the general ability to persist disturbance” (Folke 2006).

Carpenter et al. (2001) interpret socio-ecological resilience as:

  1. 1.

    The amount of disturbance a system can handle and still remain in the same state,

  2. 2.

    The degree of a system to be self-organized,

  3. 3.

    The degree to which the system can build and increase the capacity for learning and adaptation.

This further challenges the equilibrium state of engineering and ecological resilience as this view highlights the ever-evolving state of system without having to go through drastic disturbances. Therefore, Kim and Lim (2016) describe it as “evolutionary” resilience since it examines the evolutionary process of a society. However, the term “evolutionary” mentioned here has a slightly different meaning. It includes flexibility, diversity, and adaptability, thus improving the capacity through a constant process of adaptation (Kim and Lim 2016).

Research on ecosystems has led to a deeper understanding of the important role that biodiversity plays in self-organizing of complex adaptive systems in relation to absorbing a shock and reorganizing of the system after the disturbance or shock (Folke 2006). The adaptive cycle developed by C. S. Holling is applicable in complex adaptive systems in relation to ecosystems and social systems through the process of non-linear changes. It describes the way a complex adaptive system evolves in four stages, namely, rapid growth (r), equilibrium (K), collapse or destruction (Ω), and reorientation (α) (Folke 2006). The adaptive cycle in Fig. 4.1 describes the movement of the system through a three dimensional state: system potential, connectedness, and resilience (Holling, 1986).

Fig. 4.1
figure 1

(Source Holling, 1986 in Garmestani et al., [2009])

The adaptive cycle

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The Panarchy (Fig. 4.2) by Gunderson and Holling (2002) shows nested adaptive cycle indicating that the processes that give shape to an ecosystem take place at different spatial and temporal scales. According to Kim and Lim (2016), the adaptive capacity cycle needs to evolve continuously to be able to evolve continuously and experience transition into a state that has greater amount of resilience and allows continuous interactions between various features such as adaptability and transformability (Kim and Lim 2016). Sundstorm and Allen (2019) firmly argue the adaptive cycles to be ubiquitous in complex adaptive systems as they are continuously generating dynamics due to self-organization and evolution processes.

Fig. 4.2
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(Source Kim and Lim 2016)

The panarchy adaptive cycle

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Research on socio-ecological systems considers that there is more than just social and ecological systems combined. Most of the literature available on resilience from 2000 onwards adopted the term “socio-ecological system” exclusively considering the social side of it to address global challenges (Berkes and Ross 2013).

2.2 Emergence and Spread of Urban Resilience

While the concept of resilience has been addressed and researched upon by different academicians and scientists from different study fields, it was not until the early years of the new millennium that it was widely used in urban studies (Sharifi et al. 2017). Since then, the application of this concept has been constantly changing more along with the changes in the urban environment; hence, it is considered as an “evolving concept” (UN-Habitat 2017). Cities are considered as the part of the problem due to high emissions of greenhouse gases and increase in vulnerability to risks yet; they are also parts of the solutions they can provide opportunities for better and more efficient coping and response. With the rise in catastrophic events, urbanization process, and population density, urban resilience has become a major agenda for urban planners and policy thinkers. Due to the increasing pressure that challenges the well-being of citizens, many cities are adopting resilience frameworks to also accelerate transition toward economic, socio-cultural, and environmental sustainability.

Frantzeskaki (2016) recognizes five benefits of urban resilience in cities at strategic and program level. They are as follows:

Strategic Level

  • As an integrated concept, resilience allows connecting goals and actions across various departments for being able to develop a common goal and agenda for achieving it,

  • Urban resilience helps in building up solutions that systematically address vulnerabilities and risks,

  • As a transformative concept, it requires approaches that address characteristics such as redundancy and flexibility.

Program Level

  • It is a multifaceted concept that requires in-depth understanding of socio-cultural, ecological, economic, and institutions factors along with assets and vulnerabilities.

  • It is an empowering concept for community engagement as it looks into understanding risks to overcome social issues and vulnerabilities of the citizens.

Hence, different approaches are required to shift from just theoretical knowledge gain and servicing to experimental approaches with the residents to create community development and resilience.

Cities are considered as complex adaptive system, wherein, the communities and the environment are interdependent along with other subsystems, and the concept of resilience is seen as a help to face the challenges of a complex socio-ecological system (Frantzeskaki 2016).

Traditionally, urban resilience is closely linked to “engineering resilience” where the urban system is seen to have a stable state, and disturbances are attended one by one without considering the interconnectedness of social and economic factors to a city’s system. However, the static nature does not capture the dynamism of cities. According to UN-Habitat (2017), it is necessary that the entire system needs to be viewed as a whole for achieving urban resilience rather than having delivered programs that address urban challenges separately.

Figure 4.3 makes it clear that engineering resilience may be problematic as it is only focusing on a single state and does not consider non-physical factors. While the ecological approach still shows some flexibility and recognizes the characteristic of adaptability in a system.

Fig. 4.3
figure 3

(Source UN-Habitat 2017)

Analysis of resilience thinking

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Implementation of resilience in a city is not merely about responding to shocks or stressors but also the way it is perceived and understood as a concept (Shamsuddin 2020). Greater and efficient multilevel stakeholder engagement at vertical and horizontal levels will enable interconnecting resilience in policies, economic development, and in reducing climate-induced impacts. The idea of urban resilience is multifaceted and highly challenging. Therefore, there is a need to bridge the gap between theory and implementation of urban resilience (Coaffee et al. 2018).

Factors such as availability of resources, coordination between government departments, documentation procedures, and willingness from officials can highly influence the implementation process. To restructure the functions and activities of government departments in a traditional bureaucratic setup and shit toward horizontal integration is a major task for developing resilience (Coaffee et al. 2018).

Collaboration with private sector for services such as IT, investments, consultancies, and think tanks will further enhance the process of building resilience in a city. The Resilient Cities Congress held in 2018 had promoted the inclusion of private sector. Along with government and private sectors, communities play an important role in building resilience. Inclusion of communities in building resilience will help in better understanding of the social fabric of a city which will further lead to better decision-making processes (Frantzeskaki 2016).

2.3 Advances in Urban Resilience

An increasing number of international organizations has developed frameworks and formed alliances addressing their concerns related to the concept of resilience. The C40 Cities Climate Leadership group established in 2005 aims to make the registered 95 cities climate resilient. Another major project dedicated to help cities become resilient in social, economic, and physical aspects is the “100 Resilient Cities” pioneered by the Rockfeller Foundation. It helps formulate each city a resilient strategy that shall further inspire other cities of all sizes to adopt resilience.

The 2030 agenda for sustainable development comprises of 17 goals out of which the Sustainable Development Goal 11 looks specifically into making cities resilient, inclusive and sustainable. A non-governmental organization, Cities Alliance works for eradicating poverty in cities through programs that support strengthening policy frameworks, building local skills and capacity, implementing strategic urban planning, and facilitating investments. The Ecological Sequestration Trust in 2011 was formed to improve energy, water, and food security at city-regional scale.

“Resilient Cities” Congress in 2018 organized by ICLEI is considered to be one of the major events on urban resilience that brought various policy makers and a few researchers together to focus on natural disasters specifically, and discuss policies and mechanisms required to mitigate them in cities. According to a research conducted by Rogov and Rozenbalt (2018), the term “urban resilience” is more linked with to ecological concepts such as “natural disasters,” “ecosystem services,” and “climate resilience” while it is very rarely linked with social and economic domains.

Urban living labs are considered to be a place-explicit experimentation in neighborhoods and cities which promote the involvement of various stakeholders like residents, municipal, and local authorities, knowledge partners and other private actors to find solutions to urban challenges in the concerned area. This helps in generating new knowledge on urban issues that are under-researched and will effectively help in implementing solutions. Voytenko et al. (2016) have presented five characteristics of an urban living lab: (1) Geographical embeddedness, (2) experimentation and learning, (3) participation and user involvement, (4) leadership and ownership, and (5) evaluation and refinement.

As cities continue to grow, they need to deal with uncertainties and challenges like climate change, food insecurity, lack of essential services to the poor, urban waste and water mismanagement, and lack of effective land use planning that could result in construction on risk prone areas. Such unfavorable circumstances lead to inequalities in cities which further create social unrest and increase the chances of riots. Thus, urban resilience is turning out to be a favorable concept that can help cities derive maximum benefits from agglomeration of economies and help in minimizing externalities (Ribeiro and Gonçalves 2019).

3 Urban Resilience Concepts and Definitions

From the vast body of research available on the concept of urban resilience, in this section, 30 definitions are reviewed and presented from the most influential publications. Out of the mentioned definitions, some of are similar yet unclear due to the divergent contexts of urban. The definition of urban resilience presented in Table 4.1 are sorted according to the study domain they have been mentioned in, such as agricultural and biologicals sciences, engineering, environmental sciences, social science, management and accounting, and energy.

Table 4.1 Definitions of urban resilience
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As seen from Table 4.1, most of the definitions are either based on the context of threat to a system or on urban sustainability. However, the main aim of all studies and definitions is to add quality to the living conditions of the urban residents. The area of study which highlighted the most about resilience is climate studies or climate change—since it is considered to be one of the major challenges along with urbanization and population growth in cities (Ribeiro and Gonçalves 2019).

According to Meerow et al. (2016), certain number of definitions are underdeveloped and have not addressed the conceptual tensions that exist in accordance to urban resilience. Some of the key conceptual tensions are:

  1. 1.

    Characterization of urban: Definitions of urban resilience are mostly considered as vague as they do not define the meaning of “urban,”

  2. 2.

    Notion of equilibrium: While certain definitions of resilience depict single-state equilibrium others adopt the notion of multi-state equilibrium,

  3. 3.

    Resilience as a positive concept: The definitions mentioned in the tables embrace urban resilience as a positive and a desirable characteristic,

  4. 4.

    Pathway to resilience: The definitions specify three pathways to resilience, that are, persistence, transition, and transformation,

  5. 5.

    Understanding of adaptation: The next tension builds around the concept of adaptation which means that certain definitions are built on such specific context which is undermining the system’s flexibility and ability to cope during sudden and unexpected threats. There are many definitions in the literature which focus on general adaptability and flexibility to prepare the situation under any sort of threat,

  6. 6.

    Timescale of action: Only a certain number of definitions reflect upon the time scale of the system after the disturbance under the fields of natural disasters and climate change. None of the other definitions’ emphasis on the speed of recovery.

The definition developed by Meerow et al. (2016) specifically addresses these six tensions which is flexible to be used by researchers from any field. The definition also offers multiple ways to be resilient and most importantly recognizes the timescale in terms of taking an action. While Ribeiro and Gonçalves (2019) build on the table by Meerow et al. (2016); yet, their definition focuses on the four basic pillar of resilience, that are, resistance, recovery, adaptation, and transformation. However, the main difference that exist in all the definitions presented above lies in the way they have conceived a system to absorb, tolerate, adjust, reorganize, support, resist, respond, recover, and transform from the disturbances.

4 Dimensions and Characteristics of Urban Resilience

4.1 Dimensions of Urban Resilience

Urban resilience can be divided into dimensions that are important for characterizing and evaluating resilience. Ostadtaghizadeh et al. (2015) conducted a study to examine the tools and models available for community disaster resilience assessment. The research summarized various dimensions, mainly divided into five parts as shown in Table 4.2: (1) Natural (2) Infrastructural (3) Economic (4) Institutional, and (5) Social.

Table 4.2 Dimensions and sub-dimension
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While Ostadtaghizadeh et al. (2015) summarized the indicators broadly into these five dimensions, the availability of definitions and concepts regarding these domains makes it difficult to form a common framework. This calls for an international attention for developing a framework to be used as a foundation for the development of resilience plans and programs in cities. Another important aspect, while developing measures that are valid and reliable is to first establish the “cross cultural utility of the variables” (Ostadtaghizadeh et al. 2015).

Similarly, Sharifi (2016) also carried out an analysis from various studies based on community resilient assessment tools to develop a framework that could be used to evaluate the performance of the resilient assessment tools by addressing to multiple dimensions and their sub-dimensions along with their resilience criteria. The dimensions he focused on are: environmental, social, economic, built environment and infrastructure, and institutional. Built environment and infrastructure dimension addressed by Sharifi (2016) is what Ostadtaghizadeh et al. (2015) has described as “physical” dimension.

Ribeiro and Gonçalves (2019) have defined the five dimensions in their research based on the same dimensions developed by Ostadtaghizadeh et al. (2015):

  1. 1.

    Physical Dimension: “…includes the assignment of the resilience in infrastructures”

  2. 2.

    Natural Dimension: “…includes the ecological and environmental resilience”

  3. 3.

    Economic Dimension: “…includes the development of societies and economies”

  4. 4.

    Institutional Dimension: “… includes the governance and mitigation policies”

  5. 5.

    Social Dimension: “…resilience of communities and people in general”

After careful examination and analysis, Ribeiro and Gonçalves (2019) and Sharifi (2016) observed that institutional and social dimensions were discussed most often in the literature. These two dimensions show a strong link between themselves which means that measures such as leadership and strategic structure are critical for building resilience in an urban area (Ribeiro and Gonçalves 2019). On the contrary, the environmental dimension receives very limited attention despite having importance in building resilience of a city (Sharifi 2016). Being a multifaceted concept, it is best to achieve resilience by looking into all the five dimensions. Hence, Sharifi (2016) emphasize paying more attention to the environmental dimension along with other dimensions.

Cutter et al. (2010) in their research described the dimensions with respect to disaster resilience. While they considered the social, infrastructural, institutional, and cultural components or dimensions, they did not consider the fifth dimension of environment separately but rather included it in the institutional dimension. This replaced the fifth element to community dimension. The dimensions are described as below:

  1. 1.

    Social: This dimension aimed at addressing the differences that persist between and among the communities by creating between the demographic segments to social capacity.

  2. 2.

    Economic: This dimension measures the economic attributes of citizens such as employment type and amount, homeownership, division of incomes, and business size.

  3. 3.

    Institutional: It aims at addressing sub-components of mitigation, planning, and earlier disaster events and experiences.

  4. 4.

    Infrastructural: It is based on community’s capacity to respond and recover. It includes assessment of aspects, such as the number of private owned property that is vulnerable to the risks and economic loses.

  5. 5.

    Community: In broader terms, this dimension falls under social dimension; however, it assesses an individual’s relations between their neighborhood and community. Sense of community, public participation, and place attachment are three elements that are required to be understood.

Hence, we observe that the dimensions of resilience might differ if put under the context of a specific types of resilience such as disaster resilience (Cutter et al. 2010). This makes the point of having a basic framework that can be modified according to the field, more affirmative.

4.2 Characteristics of Urban Resilience

After discussing the definitions and dimensions of urban resilience, there is a need to identify the characteristics for the evaluation of resilient frameworks of urban systems which in their origin are complex since the technical components come together with the social ones. The available literature discusses resilience characteristics in different contexts such as community-based resilience, urban energy system, resource efficiency, and urban climate change. However, the mentioned characteristics in these papers are not only specific to their mentioned concept but rather, urban resilience as a whole.

Ribeiro and Gonçalves (2019) identified eleven relevant characteristics that would make an urban system resilient enough, they are related to redundancy, diversity, efficiency, robustness, connectivity, adaptation, resources, independence, innovation, inclusion, and integration. The aim to identify these characteristics was to make it easier and efficient for the local stakeholders to implement their resilience frameworks. They argue that there is a need for the local stakeholders to frame urban resilience in a way that is flexible and adaptable in relation to everchanging global environment and to the needs and specific situation of a locality.

Sharifi and Yamagata (2016) present resilience characteristics as “principles” necessary for the urban energy framework developed for assessing energy resilience in an urban system. Further, Tyler and Moench (2012) and Spaans and Waterhout (2017) present resilience characteristics in their respective conceptual frameworks for assessing urban climate adaptation in cities. Building on the characteristics described by various researchers, 14 characteristics, that are, robustness, diversity, redundancy, connectivity, flexibility, resourcefulness, agility, efficiency, adaptive learning, modularity, creativity, equity, inclusive, and foresight capacity have been identified and described for making a city resilient.

Robustness: The ability of a system to withstand a shock or stresses without the major functions and roles of a system undergoing a dynamic shift (Sharifi and Yamagata 2016). A system needs to be well-conceived, designed, and managed to be able to withstand the external forces (Spaans and Waterhout 2017). With the anticipation ability to predict potential failures and ensure safety, a system ensures that it is robust.

Redundancy: This characteristic means having extra components as spare capacity just in case. Having redundant capacities and functions is essential as they can compensate for the failed components in case of major disruptive events (Tyler and Moench 2012; Sharifi and Yamagata 2016). This ensures that the entire system would not stop functioning due to failure of one component. The substitutable component should be a high-level priority at a city level and cost-effective (Spaans and Waterhout 2017). Tyler and Moench (2012) term it as safe failure where the interdependence of functions or the system supports each other which avoids the entire system to fail. In other words, the major services can still be delivered despite a system failure.

Flexibility: A flexible urban system means that it has the capacity and ability to adapt itself to changing conditions or if a system goes through disturbances and disruptions. Such a system can immediately detect threats and failures and evolve and adapt accordingly (Sharifi and Yamagata 2016; Spaans and Waterhout 2017). According to Roggema (2014), in a flexible urban system both physical and functional elements should be designed and developed in a way that would allow disassembling and rearrangement. This would ensure multifunctionality of the system to cope with disturbances in a shorter time frame. This calls for the system to execute necessary tasks under different types of conditions and modifying assets in regard to new conditions (Tyler and Moench 2012). To achieve flexibility, introduction of new technologies and/or integrating indigenous knowledge is a useful approach (Spaans and Waterhout 2017).

Agility: It is imperative for a system to return to its normal or better functionality by mobilizing its resources in a given time period (Sharifi and Yamagata 2016). According to Sharifi and Yamagata (2016), this process should be exhibited in a timely manner to achieve resilience.

Adaptive Capacity: This characteristic would help in determining the vulnerabilities to future shocks and stresses enhancing the adaptation process under changing conditions (Sharifi and Yamagata 2016). The adaptation process also includes having the appropriate knowledge and ability to respond rapidly to shocks and stresses in an urban system (Ribeiro and Gonçalves 2019). The ability to learn from past experiences and events would help in building capacity of a system to respond accordingly and improve its performance (Tyler and Moench 2012). It is necessary for the actors and institutes to keep gathering new knowledge for enhancing resilience in their city (Tyler and Moench 2012; Sharifi and Yamagata 2016).

Modularity: Another way to strengthen an urban system’s resilience is to develop self-organization in a system which doesn’t allow centralization of power and resources or relying on outside physical intervention (Ribeiro and Gonçalves 2019; Sharifi and Yamagata 2016). This characteristic centers around strengthening local community engagement, cross sectoral partnerships, and vertical and horizontal institutional setup for informed decision-making process (Sharifi and Yamagata 2016). The system should be independent and self-reliant to be able to function the bare necessity when going through a disturbance.

Resourcefulness: The various actors responsible for building a city’s resilience should always ensure the availability of sufficient resources to identify, plan, and respond to risks and disruptions (Sharifi and Yamagata 2016). This means the citizens should have the option of meeting their basic requirements readily available. This also includes access to financial assets and other assets of the actors who are collaborating in making an urban system resilient (Tyler and Moench 2012). Hence, heavy investments are required in anticipating events and setting priorities (Spaans and Waterhout 2017).

Creativity: This characteristic emphasizes importance of integrating technological and non-technological innovation into management and planning aspects of an urban system (Sharifi and Yamagata 2016). It is necessary for strengthening the ability of restoring a system’s functioning under limited conditions (Ribeiro and Gonçalves 2019).

Equity: It is considered to be one of the most essential characteristics for achieving resilience. For an energy system, for instance, it is based on fairly distributing the energy resources across the city and ensuring accessibility. Also, just options should be provided to the ones bearing the brunt of the consequences during production, transmission, and distribution of energy (Sharifi and Yamagata 2016).

Foresight Capacity: A resilient system should be able to anticipate future uncertainties and situations along with having the ability to visualize possible outcomes and consequences (Sharifi and Yamagata 2016). This characteristic is considered to be necessary for disaster management and absorbing an initial shock. Lack of this characteristic might exacerbate the risk when exposed to hazards and disasters (Sharifi and Yamagata 2016).

Diversity: It works on the principle that there should be various options available to deal with disturbances and disruptions in a city—with more options, the ability to adapt to a diverse set of circumstances will increase (Ribeiro and Gonçalves 2019). According to Tyler and Moench (2012), a resilient system has two types of diversity—spatial and functional diversity. Spatial diversity would mean that all the functions of a system are not affected at one particular time, while, functional diversity would make a resilient system have more than one way to meet a given need (Tyler and Moench 2012).

Inclusiveness: Day by day it is being considered necessary to facilitate the participation and involvement of institutes, increasing community involved practices, mobilization of resources during recovery period, and smooth flow of information among the stakeholders through horizontal and vertical integration (Sharifi and Yamagata 2016). Transparency, accountability, and responsiveness are the widely acknowledged principles of good governance (UNDP 1997) needed for decision-making process especially including the vulnerable. These offer a sense of shared ownership for building resilience of city.

Connectivity: It is important to have a system where there is efficient coordination of various preparatory and recovery actions among various stakeholders from different sectors. Without such a characteristic, the system would fail to recover after going through a shock (Sharifi and Yamagata 2016; Riberiro and Gonçalves 2019).

Efficiency: This characteristic aims at building a positive relation with the functioning of a system with a static nature along with the systems that operate dynamically (Ribeiro and Gonçalves 2019). In terms of resource consumption, it is necessary for a city to have a resource efficiency agenda that will help a city become resilient by reducing the risk of shortfalls in essential resources, such as water, food, energy, and materials. Resources help in functioning of a city and being resilient would mean more efficient resource use and management (UNDP 1997).

The resilience of a system is exhibited only while going through shocks and stresses. However, these characteristics of the system exist irrespective of the exposure to disturbances (Tyler and Moench 2012). The characteristics of an urban system should be seen as functioning in a complex and interconnected network that do not function in isolation. Also, they should not only be viewed from a technical perspective. Every urban system would be different, and so it is impossible to provide specific solutions for all conditions and disturbances. However, the growing literature can help in providing a fundamental framework for these characteristics by establishing a fundamental or baseline framework. This way, it becomes easier to monitor changes is resilience which further helps in comparing one place to another (Cutter et al. 2010).

5 Conclusions

We are now living in the era of increasing risks and uncertainties. Annually, cities are hit with different types of adverse events ranging from natural disasters to political conflicts and public health crises. Indeed, many cities are already vulnerable to adverse events and, in many parts of the world, conditions may become more sever considering the projected trends of urban population growth. Climate change is expected to further increase the frequency and intensity of adverse events, and this is likely to further increase the pressure on cities and their already constrained resources. Additionally, the recent pandemic demonstrated that cities need to also plan and prepare for major public health crises in future (Sharifi and Khavarian-Garmsir 2020).

It is due to increasing awareness about such threats, risks, and uncertainties that many cities around the world are increasingly building on their efforts to enhance urban resilience. This is manifested in the increasing number of plans, programs, policies, and frameworks that are developed annually in many cities around the world. Through investment in such initiatives, cities expect to minimize potential losses in future and ensure building capacities to better respond to, recover from, and adapt to adverse events. One potential impediment to the proper design and implementation of resilience plans, programs, policies, and frameworks is the incomplete understanding of the resilience concept itself. This issue becomes even more complicated when considering the fact that resilience is a contested notion and various definitions exist for it depending on the background, field, context, and objectives of the stakeholders.

In an effort to better understand different conceptualizations of resilience in the context of urban planning, this chapter elaborated on the genealogy of the resilience concept and its underlying principles and characteristics. It was argued that resilience as a concept has an old history in fields such as physics and psychology. In such fields, resilience has mainly focused on abilities to absorb shocks and return to pre-shock equilibrium conditions in a timely manner. Unlike other fields, resilience has been introduced to and used in urban studies only since a few decades ago. In their conceptualizations of resilience urban scholars have been particularly influenced by ecologists. In the ecological domain, it is recognized that return to pre-disaster equilibrium state may be neither possible nor desirable. Instead, depending on the severity of the shock and the conditions of the system, it may transform into a new state(s). This is well-aligned with urban issues and phenomena, as cities are often considered as socio-ecological systems. In addition to ecology, urban scholars and practitioners have relied on the vast body of literature from other fields to conceptualize resilience depending on their specific purposes. In fact, the wealth of literature published in other fields have provided an opportunity to adopt the resilience concept flexibly in urban research and practice. Generally, the dominant approaches that guide such conceptualizations of urban resilience are categorized as engineering, socio-ecological, and adaptive. The latter one has gained more momentum in the recent years considering the increasing recognition of the concept of living with risk and the need for continuous improvement and evolvement.

This chapter is concluded by elaborating on various underlying resilience characteristics such as robustness, redundancy, flexibility, agility, adaptive capacity, modularity, resourcefulness, creativity, equity, foresight capacity, diversity, inclusiveness, connectivity, and efficiency. These characteristics are essential for developing more objective resilience plans, programs, policies, and frameworks. They could also contribute to making the resilience concept more tangible to various stakeholders. These characteristics have also guided design and implementation of case studies that have been reported in the latter part of this volume.