How can socio-hydrology contribute to natural disaster risk reduction?

ABSTRACT

Despite scientific progress and international efforts, records of natural disasters and their losses are increasing. Natural disasters are constituted by the mutual interactions between social and environmental factors over time and space. Hence, the challenges of this dramatic scenario demand that we understand the interwoven social and environmental processes. Against this background, a perspective that understands humans and nature as a coupled system, like the socio-hydrological approach, can be a key to disaster risk reduction. We conducted exploratory research to demonstrate the potential of socio-hydrology to contribute to natural disaster risk reduction according to two central arguments: (i) developing an understanding of bidirectional interactions between social and environmental factors; and (ii) supporting integrated water resources and disaster risk management. As a result, we propose an integrative framework based on internal interactions between social and natural sciences, and also external interactions between the scientific community and society.

KEYWORDS:

• integrated management
• natural hazard
• societal organization
• dichotomous thinking
• interdisciplinarity

Editor S. ArchfieldGuest editor S. Pande

Introduction

Natural disasters result from interactions between natural hazards and population characteristics, causing negative impacts on the functioning of a society. Both societal and environmental factors play an important role in determining the impacts and losses of disaster (World Bank and United Nations 2010, Massazza et al. 2019). Due to the interdisciplinary aspects of natural disaster, several disciplines are dedicated to studying risk and disaster (e.g. Knez et al. 2018, Santos 2019, Skilodimou et al. 2019, Zhou et al. 2020). However, there is a gap between the social and natural sciences in terms of analysing extreme events (Rusca et al. 2021).

Despite scientific progress and international efforts like the Sendai Framework for Disaster Risk Reduction 2015–2030 (UNDRR 2015), economic losses associated with natural disasters, excluding biological disasters, almost doubled from the period 1980–1999 to 2000–2019, and the total deaths did not decrease between these periods (UNDRR 2020). The challenges to improve this serious situation demand that we understand the relevant interwoven social and environmental processes because natural disasters are constituted by the mutual interactions between social and environmental factors over time and space. From this perspective, we argue that understanding humans and nature as a coupled system, as does the socio-hydrological approach, can be a key to disaster risk reduction.

Many subjects of socio-hydrology are closely related to the essential points of natural disaster studies. However, socio-hydrology has potential to contribute to natural disaster risk reduction that is not yet well explored. Against this background, we conducted exploratory research based on two central arguments. The first argument is that socio-hydrology research can help in understanding the feedback mechanisms between natural hazards and societal organization over time and space. The second is that in addition to socio-hydrology’s contribution to integrated water resources management (IWRM) (Sivapalan et al. 2012, Di Baldassarre et al. 2019), its contribution can be broadened by including natural disaster risk management.

To provide solutions for the aforementioned gap, the present study proposes an integrative framework of socio-hydrology to contribute to natural disaster risk reduction. This framework is based on internal interactions between natural science and social science, and also on external interactions between the scientific community and society.

Natural disaster as a result of negative interactions between environmental and social factors

Disaster is defined as a serious disruption of the functioning of a community or a society at any scale due to hazardous events interacting with conditions of exposure, vulnerability, and capacity, leading to one or more of the following: human, material, economic, and/or environmental losses and impacts (UNDRR 2016). The Centre for Research on the Epidemiology of Disaster (CRED) classifies disasters into two types based on hazard sources: natural and technological (Below et al. 2009).

Thus, natural disaster refers to a disruption of the functioning of society as a result of negative interactions between natural hazards and social characteristics. A disaster’s impacts depend on both environmental and social factors, where it is not possible to define which is the cause and/or the effect. Natural hazards, even if their triggering factors may be of anthropogenic origin, are controlled by natural phenomena (Vilímek and Spilková 2009). On the other hand, natural hazards cannot generate natural disasters without the presence of humans (UNDRR 2020).

With this in mind, several researchers have been discussing the “unnaturalness” of natural disasters (e.g. O’Keefe et al. 1976, Gould et al. 2016, Mattedi 2017, Massazza et al. 2019). These researchers argue that the hazards may be natural, but the disaster is an effect of societal actions. Massazza et al. (2019) highlighted that earthquake survivors describe the damage as something inherently social and political, with human agency playing a central role in mediating the forces of nature. Some suggest the use of the term “socio-natural disasters” to convey that disasters are socially constructed but have natural triggers (Chmutina and von Meding 2019).

Since natural disasters are products of natural and social dimensions, both natural and social sciences have been dedicated to studying disasters from their own perspectives. Researchers in natural sciences focus on the hydrological, meteorological, geomorphic, and geophysical processes and other natural aspects, while social scientists study societal organization, psychological traumas, institutional behaviours, and so on (e.g. Knez et al. 2018, Santos 2019, Skilodimou et al. 2019, Zhou et al. 2020). Individually, each scientific discipline attempts to understand aspects of the disaster by using its own research approaches and analyses, which can often construct barriers to communication among these sciences. For instance, in working as a sociologist at a Brazilian warning agency, Marchezini (2020) reported that his colleagues (meteorologists, civil engineers, environmental engineers, physicists, mathematicians, and geographers) used to ask him, “What is a sociologist doing here?”

Despite the fact that natural disasters are multifaceted, two approaches predominate in natural disaster studies: the hazard paradigm and the vulnerability paradigm (Gilbert 1995, Gaillard and Mercer 2012, Blöschl et al. 2013, Jackson et al. 2017). The first paradigm focuses on natural hazards (independent variables), where communities (dependent variables) react against an external agent (hazard). The second paradigm, in contrast, focuses on social aspects, where the disaster is no longer experienced purely as a reaction to a natural phenomenon; rather, it can be seen as an action, a result, and, more precisely, as a social consequence.

Alternatively, Gilbert (1995) proposed a third paradigm: the uncertainty paradigm. It can be described in terms of three key points: (i) the disaster is linked to the uncertainty that occurs when a hazard – real or not – threatens a population, and the hazard cannot be defined through causes or effects; (ii) uncertainty emerges from modern society, as the product of community organization and not of external factors; and (iii) uncertainty also lies in the communication problems – the excess and the absence of information – taking place within communities. Meanwhile, Di Baldassarre et al. (2018a) argued for an integrative research framework between hazard and vulnerability paradigms for assessing whether and how diverse forms of community organization and behaviour give rise to different outcomes.

The hazard and vulnerability paradigms evince dichotomous thinking in natural disaster research. Other dichotomous ways of thinking are also recognized: top-down and bottom-up frameworks, global scientific knowledge at the detriment of local actions (Gaillard and Mercer 2012, Aitsi-Selmi et al. 2015), structural and non-structural measures, natural and social science methodologies, quantitative and qualitative data, and also global versus local spatial scales. Each side of these dichotomies has its advantages and limitations. In other words, when choosing one or the other option for studying a natural disaster, only one aspect – environmental factor or social factor – will be emphasized. In this sense, Jackson et al. (2017) mentioned that each paradigm creates its own disaster risk reduction system, where the system implemented by the hazard paradigm is, generally, different from that implemented by the vulnerability paradigm. Therefore, the dichotomous thinking in natural disaster research should be replaced by an integrative approach – like the socio-hydrological approach.

Current natural disaster risk management

The Sendai Framework for Disaster Risk Reduction 2015–2030 is a global voluntary agreement that aims to achieve disaster risk reduction and to build disaster resilience (UNDRR 2015). The goals of the Sendai Framework are the substantial reduction of mortality, affected people, and losses and damages related to disasters by 2030. This framework emphasizes the need for a more integrative disaster risk reduction management, overcoming the current dichotomous thinking.

In addition, the Sendai Framework proposes the strengthening of the steps that precede the extreme event. The cycle of disaster management consists of three interlinked steps: pre-event, event, and post-event (Fig. 1). Disaster risk management is proactive by acting in the pre-event step (mitigation, prevention, and preparedness) and warning about the event. In other words, disaster risk management refers to strategies and policies to prevent new disaster risk, to reduce existing disaster risk, and to manage residual risk, by contributing to strengthening resilience and reducing disaster losses (UNDRR 2016). Meanwhile, disaster management is reactive by acting in response to disasters and in the post-event step (recondition, recovery, and reconstruction).

Figure 1. The cycle of disaster management

According to the global Emergency Disasters Database (EM-DAT: https://public.emdat.be/), maintained by the CRED and World Health Organization (WHO) in collaboration, the number of natural disaster records in 2019 was almost triple that of 1980, with the maximum number of records being reached in 2002 (Fig. 2). There was an abrupt increase in the records of natural disasters from 1980 to the end of the 20th century, where 523 events were recorded in 2000. Natural disasters such as the Indian Ocean tsunami in 2004, Hurricane Katrina in 2005, Cyclone Sidr in 2007, and many others generated an annual average of 448 records between 2000 and 2009. During the period 2010–2019, the annual average was 376 records, which is smaller than that during the period 2000–2009 but twice the annual average of the period 1980–1989. Furthermore, the tangible damages reached higher values during the period 2010–2019 than during the period 2000–2009. Hoeppe (2016) showed the frequency of relevant loss has increased very significantly (p < .001) since 1980. Although there are uncertainties about disaster statistics (Quarantelli 2001), the EM-DAT has been widely utilized in international disaster databases across research papers, technical reports, and policy documents (Panwar and Sen 2019).

Figure 2. Records of natural disasters, deaths per event, and total damage per event during the period between 1980 and 2019. (Data collection: 30 May 2020)

Among natural disasters, hydrological disaster occurrences are predominant. Floods were responsible for 44% of occurrences of natural disasters in the world during the period 2000–2019 (UNDRR 2020). Ward et al. (2020) highlighted the importance of simultaneous management of flood and drought for better design, countermeasures, and strategies in disaster risk reduction. Other natural disasters are also directly and/or indirectly related to water, for example storms, extreme temperature (Gopalakrishnan 2013), and volcanic activity (Walowski et al. 2015). Furthermore, water is relevant to all types of natural disasters during the disaster response step. During this step, the supply of potable water for disaster-affected people’s consumption and the supply of non-potable water to clean and disinfect their homes are fundamental to ensure public health (Pan American Health Organization 2006, Kouadio et al. 2012, Londe et al. 2014, Baeza et al. 2018, Suk et al. 2020).

Kobiyama et al. (2018) mentioned three issues linking water and natural disaster: (i) the main environmental factor causing natural disaster is the water dynamics; (ii) disaster-affected people need water, as a priority; and (iii) water dynamics on the terrestrial surface is normally controlled by river basins. In this context, natural disasters and water are strongly interlinked, and the current management of both issues represents a challenge to achieve the goals of the Sendai Framework, and consequently for sustainable development and poverty eradication (UNDRR 2015). Since water and societies are common issues in the management of water resources and natural disasters and risks, these managements should be integrated and performed concomitantly (Dalton et al. 2013, Wieriks and Vlaanderen 2015, Kobiyama et al. 2018). The integrated management of water resources and disasters must be executed to prevent the occurrence of water-related disasters and also to guarantee the water supply system after the occurrence of all types of disasters. Then, the main question becomes how to effectively integrate the management of natural disasters and water resources, aiming for disaster risk reduction.

Review of socio-hydrology’s contribution to natural disaster studies

In the last decade, socio-hydrological studies have highlighted bidirectional interactions between social and environmental factors. Sivapalan et al. (2012) presented socio-hydrology as the science aiming to understand the dynamics and co-evolution of coupled human–water systems. The Scientific Decade 2013–2022 proposed by the International Association of Hydrological Sciences (IAHS) encouraged discussions about the interactions between hydrology and society (Montanari et al. 2013). In his book chapter (in Japanese), Kuraji (2007) argued for the importance of “forest socio-hydrology” by noting that problems of forest–water relations are not only issues of natural phenomena but also those of history, culture, society, economy, and politics. Similarly, we claim socio-hydrology for disaster risk reduction because the problems related to natural disasters are the result of not only natural phenomena but also societal organization.

Incentives and popularization of socio-hydrology can be productive and effective for increasing knowledge of natural disasters and their management. Nevertheless, a search of the Web of Science (WoS) database for studies involving socio-hydrology and natural disasters returned only 15 peer-reviewed articles and two editorials (Table 1). The search terms used in the present study were ((“socio-hydrology” OR “sociohydrology” OR “socio-hydrological” OR “sociohydrological” OR “socio-hydrologic” OR “sociohydrologic”) AND (“natural disaster*”) OR (“natural risk*”) OR (“natural hazard*”)) in the title, abstract, author’s keywords, or keywords plus® of publications for the period 1945 to 2020.

Table 1. Publications related to socio-hydrology and natural hazard/risk/disaster listed by the research on the Web of Science database until 2020

Reference	Characteristics of study	Objectives of study
Montanari and Koutsoyiannis (2014)	Editorial	Stationarity
Gober and Wheater (2015)	Editorial	Socio-hydrology and flood risk
Grames et al. (2016)	Mathematical model with dynamic optimization focus on floods	Socio-hydrological model of high-water-level events potentially causing flood in an economic decision framework
Fuchs et al. (2017)	Questionnaire survey and statistical analyses	Socio-hydrology and flood risk perception
Di Baldassarre et al. (2018a)	Commentary	Socio-hydrology and disaster risk reduction
Di Baldassarre et al. (2018b)	Opinion	Socio-hydrology and flood
Jaramillo et al. (2018)	Mathematical model	Construction and implementation of an indicator-based approach to assess socio-hydrological systems under the influence of hydropower development
Soroush and Mordechai (2018)	Literature review	Flood management in modern societies
Xu et al. (2018)	Bibliometric review	Socio-hydrology studies analysis
Caprario and Finotti (2019)	Techniques of geoprocessing	Socio-hydrological tool for mapping susceptibility to urban flooding
Di Baldassarre et al. (2019)	Literature review	Socio-hydrology and Sustainable Development Goals
Maghsood et al. (2019)	Mathematical model and questionnaire	Socio-hydrological approach for assessing the social acceptability of flood management strategies under climate change
Nüsser et al. (2019)	Remote sensing analyses and socioeconomic surveys	Adaptative strategies in ice reservoirs
Varis et al. (2019)	Mathematical model	Resilient river basin
Buarque et al. (2020)	Mathematical model	Socio-hydrological modelling application for understanding urban flood risk
Mondino et al. (2020)	Questionnaire survey	Investigation of the role of experience and knowledge in shaping flood risk awareness
Vicario et al. (2020)	Agent-based model, a hydraulic model, and a traffic model	Flood evacuation modelling considering a combination of human behaviour, flood onset, and warning timing

Among these publications, Montanari and Koutsoyiannis (2014) did not draw parallels between socio-hydrology and natural disaster, risk, or hazards. Meanwhile, Caprario and Finotti (2019) focused on studies related only to floods as natural hazards. On the other hand, some researchers studied flood risk awareness as a primary mechanism to explain the risk dynamics in the socio-hydrological approach, considering increased awareness immediately after the occurrence of extreme events and its decay over time (e.g. Di Baldassarre et al. 2018a, Buarque et al. 2020, Mondino et al. 2020). Besides the search results, various scholars have been dedicated to understanding bidirectional interactions between floods and society (e.g. Di Baldassarre et al. 2013a, 2013b, Viglione et al. 2014, Di Baldassarre et al. 2016, Haer et al. 2019) and also droughts and society (e.g. Kuil et al. 2016, Di Baldassarre et al. 2017, Gonzales et al. 2017).

Thus, some discussions of water-related disasters under the socio-hydrological approach can be found. However, socio-hydrology has the potential to contribute to a wider range of research in natural disaster studies, and not only water-related disasters. Furthermore, different characteristics of social behaviours and feedback mechanisms between society and natural hazards have not yet been fully investigated. In other words, socio-hydrology can be a key science in reducing disaster risk.

Contributions of socio-hydrology to natural disaster risk reduction

The bidirectional interactions between societies and water are complex, and require a more integrative understanding. Socio-hydrology, an interdisciplinary science involving natural and social sciences, can overcome dichotomous thinking and focus on understanding the mutual interactions between environmental and social factors (Fig. 3(a)). Hence, one of the potentialities of socio-hydrology to be a key to disaster risk reduction is in improving the understanding of the coupled human–water system. In this way, the negative impacts associated with natural disasters could be minimized or eliminated by seeking harmonious coexistence.

Figure 3. Concept of natural disaster and socio-hydrology: (a) conditioning factors, consequences, and related sciences. Increasing impacts and damages from natural disasters can occur simultaneously or not; (b) population growing and interacting with natural hazards; (c) intensification of extreme events due to disharmonious anthropogenic activities. Decreasing impacts and damages from natural disasters; and (d) risk management (mitigation, prevention, preparedness, and warning) contributing to harmonious coexistence between the population and natural hazards and/or population moving away from natural hazards zone

In general, natural and social sciences apply the hazard and vulnerability paradigms, respectively; meanwhile, socio-hydrology can support the development of the uncertainty paradigm for natural disaster studies. This is because the uncertainty paradigm considers integrative thinking where both environmental and social factors are interacting with each other, and technology and information act as forcing agents.

Figure 3(b–d) demonstrates some interactions between natural hazards and population that influence the impacts and damages of natural disasters. As previously noted, technology and information are considered forcing agents influencing disaster risk reduction, positively or negatively. These bidirectional interactions between natural hazards and population, as well as different combinations of technology and (excess or absent) information, can generate different and unintended results. Political and social decisions can incentivize population expansion and settlements without public regulation at greater proximity to the natural hazard (Fig. 3(b)), or can assist the population to move away from natural hazard areas or even adapt to the natural hazard for harmonious coexistence (Fig. 3(d)). In turn, the natural environment reacts to anthropogenic activities to maintain its physical equilibrium dynamics. For instance, river straightening enhances the river velocity, affecting downstream localities, and the construction of mountain roads increases the risk of landslide disasters. Furthermore, environmental degradation intensifies climate change and alters water balance variables (Fig. 3(c)).

Although the contents of Fig. 3(b–d) are depicted separately, we attempt to illustrate the dynamics of the interactions that can occur concurrently under global and local influences. The local spatial scale is under the influence of global connections, but local heterogeneities also exert influence globally (Robertson 1994, Swyngedouw 2004). Hence, natural disasters result from the complexity that involves several uncertainties, including how the population interprets the disaster through traditional understandings and symbolic parameters.

Considering the above, another potential way for socio-hydrology to contribute to disaster risk reduction is by supporting the integration of water resource management and natural disaster risk management. This is justified because water not only triggers disasters but also is relevant to ensuring public health in all types of natural disasters, mainly during the response step. Furthermore, Sivapalan et al. (2012) and Di Baldassarre et al. (2019) argued that socio-hydrology supports IWRM practice. According to Di Baldassarre et al. (2019), socio-hydrology and IWRM interact with each other and must also learn from each other to achieve the Sustainable Development Goals (SDGs) of the United Nations Agenda 2030 (presented by UN 2015). This agenda recognizes and reaffirms the urgent need to reduce disaster risk to achieve the SDGs. From this perspective, we argue that besides the fact that socio-hydrology contributes to the IWRM, this science can play a much more important role by including natural disaster risk management as well as by contributing to the achievement of the Sendai Framework goals and the SDGs.

Based on the understanding that natural disaster studies and socio-hydrology share similar themes and that socio-hydrology can contribute to natural disaster risk reduction, the first step is to overcome the dichotomous thinking from the natural and social sciences with a truly integrative use of quantitative and qualitative data and methods. For this, we propose a framework of socio-hydrology that contributes to natural disaster risk reduction by considering internal interactions between natural science and social science, and external interactions between the scientific community and society (Fig. 4). This framework supports Integrated Water Resources and Disaster Risk Management (IWRDRM) because it provides further understanding of coupled human–water systems and incentivizes local people’s engagement.

Figure 4. Socio-hydrology framework for disaster risk reduction

Effective disaster risk management requires decentralized strategies based on a bottom-up approach (Blöschl et al. 2013), also called community-based management (Mattedi 2017). The bottom-up approach decentralizes decisions and shares responsibilities between the state and the people more easily. Meanwhile, the top-down approach (Blöschl et al. 2013), also called technocratic management (Mattedi 2017), is based on concentrating management in the state, where citizens become passive victims of disasters. A bottom-up approach, in general, has lower losses than a top-down approach (Ridolfi et al. 2020), and can also reduce the gap between the knowledge from the scientific community and the practices in policies and social programmes (White et al. 2001).

Local people’s engagement contributes to understanding the problems and solving them through the integration of local heterogeneous characteristics with global scientific knowledge. The bottom-up approach can be strengthened by using the school catchment. Kobiyama (2009, 2019) proposed that the school catchment, which refers to any experimental catchment which serves for both scientific research and environmental education activities, can be a good tool for citizen science involving active social participation and the understanding of bidirectional interactions between water and society. Educational activities play an important role to reduce some disaster impacts (Torani et al. 2019). The partnership between natural and social scientists and society is fundamental, and the establishment of school catchments can help to overcome dichotomous thinking.

Besides installing gauges to allow local people to record systematic data, local people can teach and learn through their experience with school catchments and their interactions with natural phenomena. Hence, school catchments can motivate the community to engage with the catchment, where people can feel and observe the environment, take photos, practise leisure activities, and so on. In this way, people in the local community can (i) provide data to socio-hydrologists following interdisciplinary techniques, as suggested by Rangecroft et al. (2020); (ii) become more aware of ecosystem services, paying more attention to the environment; and (iii) protect themselves, and their family and neighbours, during extreme events. Communities with knowledge for self-protection can share responsibility with public authorities. In this way, each citizen has rights and duties regarding disaster risk management.

Final remarks

The present exploratory research was motivated by the recognition of the gap between social and natural sciences in natural disaster studies. We demonstrate the potential of socio-hydrology to contribute to natural disaster risk reduction by way of two central arguments: (i) developing an understanding of bidirectional interactions between social and environmental factors; and (ii) supporting the IWRDRM. The arguments are justified because reducing or minimizing negative impacts from natural disasters depends on overcoming the dichotomous thinking that separates environmental and social factors. Furthermore, we reinforce that socio-hydrology can contribute to risk reduction for all types of natural disasters because water is associated with them as a direct and/or an indirect trigger, and can help ensure the public health of affected people during the post-event step. Thus, applying socio-hydrology to understand humans and nature as a coupled system can be a key to disaster risk reduction. The following conclusions can be drawn from this research:

• Bidirectional interactions of the natural–social system over time and space are found in common between socio-hydrology and natural disaster risk reduction;

• Socio-hydrology can support disaster risk reduction by understanding how to convert negative impacts into harmonious coexistence between the environment and society;

• Overcoming the dichotomous thinking of the hazard paradigm vs. the vulnerability paradigm and including technology and information to act as forcing agents, socio-hydrology can contribute to developing the uncertainty paradigm, which is necessary for disaster risk reduction;

• The school catchment is a suitable tool of the bottom-up approach to reduce disaster risk and to strengthen the relations between local heterogeneous and global scientific knowledge;

• Socio-hydrology should pay much more attention to natural disaster risk reduction, aiming to achieve the Sendai Framework goals and the SDGs.

The main contribution of the present study is the socio-hydrology framework for disaster risk reduction. We propose the integrative use of quantitative and qualitative data and methods based on internal interactions between hydrology and social sciences and external interactions between the scientific community and society. We suggest this framework as an answer to the question “How can socio-hydrology contribute to natural disaster risk reduction?” Finally, we argue that the partnership between socio-hydrology and disaster studies represents a mutual contribution because socio-hydrologists can benefit from the considerable participation of social scientists in natural disaster research and can foster the interdisciplinary development of socio-hydrology.

Acknowledgements

The authors thank the anonymous reviewers for the relevant contributions and Leonardo Romero Monteiro for long and fruitful discussions.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The first author thanks the Brazilian National Council for Scientific and Technological Development (CNPq) for the scholarship [141384/2019-0]. This study is a part of a scientific project supported by the Coordination of Superior Level Staff Improvement (CAPES) [Finance Code 001].