We are all concerned about hazards. We want to understand the processes controlling these. We want to know how, and why these sometimes cause loss of life, property, infrastructure, and assets. All this because we are hard wired to safeguard ourselves, our community and our interests for which better understanding of hazards is a precondition.
An obvious question that springs up while trying to understand the impact of hazards relates to the secularity of hazards or disasters – whether or not these differentiate between people, and communities?
Have you ever experienced a disaster? Was the hazard impact similar on all affected persons or communities?
You would agree that the impact of disasters is not similar on all affected persons or communities. While the impact is quite severe on some, others are more or less spared. In such a situation you would be eager to know the reasons of this differential impact of hazards on people, and communities. This differential impact of a process, phenomenon or human activity upon people, and communities is understood in terms of their vulnerability.
Vulnerability refers to the chance of being affected by a hazard, and is often defined as relative lack of capacity of a person or community to anticipate, cope with, resist, and recover from the impact of a hazard. Being human dimension of disasters, vulnerability results from a range of socio-economic, cultural, institutional, political, and psychological factors that shape people’s lives as also their environment.
Some definitions of vulnerability tend to include exposure in addition to susceptibility to harm. It is however universally accepted that exposure is separate to the susceptibility element of the vulnerability since it is possible to be exposed, whilst at the same time not being susceptible to natural hazards. An earthquake resistant house (not susceptible) in an area falling in high seismic hazard (high exposure) represents this scenario.
Despite some divergence over the meaning of vulnerability, it is agreed that understanding of vulnerability requires more than just analysing the direct impacts of a hazard. Vulnerability also concerns wider environmental, and social conditions that limit people, and communities to cope with the impact of hazards.
Vulnerability can be a challenging concept to understand because it tends to mean different things to different people, and is often described using a variety of terms including predisposition, fragility, weakness, deficiency, or lack of capacity.
Vulnerability is complex
Vulnerability is not simply about poverty but the poor generally tend to be the worst sufferers of disasters. having said so it is pertinent to put forth out here that the poor, and marginalised communities often exhibit close-knit, and strong social bonds, and possess certain skill sets, and implements that considerably reduce their vulnerability. This is often exhibited in their strong coping capacity during disaster incidences. All these, often intangible, attributes of the community should therefore be taken note of while undertaking vulnerability assessment.
Poverty is however recognised as being both a driver, and consequence of disaster risk because economic pressures often force people to live in unsafe locations, and conditions. Poverty, and other multi-dimensional factors, and drivers that often enhance vulnerability suggest that susceptibility to the impact of hazards is often, but not always, associated with certain groups, including women, children, elderly, disabled, migrants, and displaced populations, amongst others.
Vulnerability is one of the defining components of disaster risk, and relates to a number of factors, and likewise vulnerability can be understood as being one of the following.
Structural vulnerability emanates from poor design, and construction of buildings, as also unregulated landuse planning that enhance the chances of structures being adversely affected by hazards.
It is important out here to appreciate that the vulnerability is hazard specific. Vulnerability of a structure constructed using earthquake safe construction techniques on a hill slope could be low for seismic hazard but high for landslide hazard. It therefore becomes necessary to assess the vulnerability for all hazards prevalent in the area.
At the same time technology utilised for the construction of structures should be taken note of while assessing their vulnerability. Apart from the technology utilised for the construction, structural vulnerability depends on quality of construction material, workmanship, and maintenance.
BIS Codes prescribed for the area should be utilized for minimizing the structural vulnerability.
It is however important to understand that the use of BIS Codes is no guarantee for the structures to remain undamaged in the disaster incidence. Codes are in fact a compromise between safety and cost, and aim at minimising loss of human lives.
The spatial distribution of natural hazards primarily depends on natural processes that include movement of the tectonic plates, influence of weather systems, and the existence of waterways, and slopes. This simply implies that the severity of hazards is not uniform in space. Enhanced probability of a person, community or structure being affected by a hazard by virtue of its being located at a certain place is referred to as spatial vulnerability, i.e. the vulnerability emanating from spatial disposition.
The cities, and other habitations located in the proximity of the coastline thus have high vulnerability to sea level rise while those located along the riverbanks have high vulnerability to floods. Persons living in mountains have high vulnerability to landslides as compared to those living in the plains. Persons living in the plains have high vulnerability to earthquake induced liquefaction wherein the ground looses rigidity, and behaves like a viscous material in which overlying structures tend to sink, as compared to the ones living in the mountains. Even amongst those living in the plains ones living in areas with water table close to the surface are more vulnerable to earthquake induced liquefaction.
It is the secondary amplification of seismic waves that makes areas over soft soil, and with shallow water table vulnerable to earthquakes. 3534 houses were destroyed, and 11000 were damaged due to this in June 16, 1964 Nigata Earthquake of magnitude 7.5.
Depth of water table, and soil characteristics have to be therefore taken note of while assessing seismic vulnerability of an area. Both these characteristics are not uniform over space, and therefore relate to spatial vulnerability.
Assessment of spatial vulnerability is particularly necessary not only in the mountainous areas where construction works effect the stability of the hill slopes, but also in river valleys where low lying areas are hit hard by routine floods.
Most of us understand, and perceive vulnerability as being a function of poverty, and the poor do generally lack capacity to cope with, and recover from disaster impact. Inequality, marginalisation, social exclusion, and discrimination by gender, social status, disability, and age are however other factors making individuals or communities susceptible to hazard impact. Dependence on uninsured informal sector, rural livelihoods, and single industry, as also globalisation of business, and supply chains are other factors influencing this susceptibility.
The vulnerability of an individual or community that emanates from the above factors is often referred to as socio-economic vulnerability. Generally speaking the vulnerability of (i) children and elderly, (ii) physically and mentally challenged, (iii) lactating and pregnant women, (iv) diseased and chronically ill, and (v) poor and destitute is generally high. It is highly important to identify persons falling under these categories during the pre-disaster planning phase so as to effectively cater to their particular requirements during the emergency, and disaster phase.
Children are particularly vulnerable during disasters. 5690 primary, and middle schools were amongst 7669 schools damaged in Azad Jammu and Kashmir (AJK), and North West Frontier Province (NWFP) in 7.6 magnitude Muzaffarabad Earthquake of October 8, 2005. 18095 school children, and 853 teachers were killed in this earthquake, which is 22% of the total casualties. Similarly 7000 schools collapsed in 7.9 magnitude Sichuan Earthquake of May 12, 2008 in which 10000 school children were killed which is 11.5% of the total casualties. Likewise 6.5% of those killed in 9.0 magnitude Great East Japan Earthquake and Tsunami (GEJET) of March 11, 2011 were school children.
Non-structural attributes generally refer to aesthetic, and functional components attached to the structure or placed within it, and apart from others these include false ceiling, lighting, sanitary and plumbing fittings, and fixtures, together with TV, computer, and cupboards placed in a building. Non-structural components account for a significant proportion of losses in an earthquake event.
Non-structural vulnerability refers to loss of functionality of the structures due to disaster impact despite the structure being safe. This might include damage to oxygen supply lines, as also malfunctioning of sensitive diagnostic, and medical care equipment due to seismic shaking.
It is highly important to figure out non-structural vulnerability, and undertake timely corrective measures; particularly in lifeline buildings including hospitals that are required to perform with higher efficiency during emergency, and disaster situations.
Other aspects of vulnerability
Poor environmental management, overconsumption of natural resources, decline of risk regulating ecosystem services, climate change, and the like also enhance vulnerability of individuals, communities, and structures, and therefore it is a must to identify the factors making these susceptible to damage, and institute timely mitigation strategies.
In addition, vulnerability is sometimes shaped by historical, political, cultural, institutional, and natural resource management processes that shape the social, and environmental conditions people find themselves existing within. These processes produce a range of immediate unsafe conditions such as living in dangerous locations or in poor housing, ill-health, political tensions or lack of local institutions or preparedness measures.
Many of the underlying drivers of vulnerability that include poorly managed urban development, are witnessing rapid increase resulting in enhanced vulnerability of masses in many countries, and regions of the world. While evidence suggests that wealthier, and well-governed countries are able to reduce disaster risks, some countries have however exhibited rapid economic growth in the previous few decades without a commensurable rate of vulnerability reduction.
Why does vulnerability matter?
By including vulnerability in our understanding of disaster risk, we acknowledge the fact that disaster risk not only depends on the severity of hazard or the number of people or assets exposed, but that it is also a reflection of the susceptibility of people, and economic assets to suffer loss, and damage.
Differences in vulnerability (and exposure) bring forth better understanding as to why some non-extreme hazards lead to extreme impacts, and disasters, while some extreme events do not. In the context of extensive risk in particular, it is often people’s vulnerability that is the biggest factor in determining their susceptibility to damage, and loss.
In the context of different hazards, some groups are more susceptible to damage, loss, and suffering than others, and likewise within these groups some people exhibit higher levels of vulnerability than others. Vulnerable groups find it hard to reconstruct their livelihoods following a disaster, and this in turn makes them more vulnerable to the effects of subsequent hazard events. This is sometimes referred to as Disaster Poverty Syndrome. Consequently, we have to reduce vulnerability in order to reduce disaster risk.
Vulnerability results from complex interplay of a number of variables. It at the same time has many dimensions, and is driven by forces operating at different levels, from local to global. Moreover, vulnerability is dynamic, and alters continuously under the pressure of these driving forces. Furthermore, the complex factors that make people vulnerable are not always immediately obvious.
The chain of the causes of vulnerability; from the underlying drivers such as socio-economic processes, to the immediate conditions that are manifest such as poor quality housing, can be both long, and complex; but by tracking it one can identify the progression of vulnerability that builds pressure on the communities. These pressures can be released by taking measures to reduce vulnerability at various points along the causal chain.
Owing to its different facets, there exist many methods for assessing vulnerability. Ideally, any assessment should adopt a holistic approach to vulnerability assessment. However in reality, methodologies are usually divided into ones that consider physical or built environment vulnerability, and others that consider socio-economic vulnerability.
Physical vulnerability assessment
Assessing vulnerability of the built environment to hazards is extremely important in ascertaining potential consequences of an event, and thereby mainstreaming appropriate risk reduction strategies into the local development planning process. Understanding the response of existing structures to potential hazards, such as seismogenic ground shaking, and cyclonic winds requires the knowledge of building materials, and engineering practices. This information base can only be reliably, and sustainably developed at the local level.
Local engineers are increasingly dedicating themselves to better understand the vulnerability of local building stock to different natural hazards. Despite this, damage and loss data related to disaster incidences that is critical to understanding futures risks, continues to be missed.
Socio-economic vulnerability assessment
Vulnerability analysis involves understanding root causes or drivers of vulnerability, together with people’s capacities to cope, and recover from disasters. Despite indicators, and indices to measure vulnerability having been created, quantifying social vulnerability remains a challenge. These indicators are usually used to track changes in vulnerability over time.
Efforts to quantify socio-economic vulnerability therefore remain limited, and this information is rarely integrated into risk assessments. Qualitative approaches to vulnerability assessment largely focus on the assessment of the capacity of the communities to cope with natural events.
At the community level, vulnerability and capacity assessment (VCA) is often implemented using participatory approach. VCA considers a wide range of environmental, socio-economic, cultural, institutional, and political pressures that create vulnerability, and is typically applied as a (i) diagnostic tool to understand problems, and their underlying causes, (ii) planning tool to prioritise, and sequence actions, and inputs, (iii) risk assessment tool to help assess specific risk, and (iv) tool for empowering, and mobilising vulnerable communities.
By identifying their vulnerabilities, and capacities, local communities could implement strategies for immediate, as also longer-term risk reduction. They could at the same time identify strategies they can implement themselves to reduce risk, and where they need additional resources, and external assistance.
Since the occurrence, and severity of natural hazards cannot be altered, reducing vulnerability is the key to reducing disaster risk. Vulnerability however exhibits strong temporal variability as the influencing processes are highly dynamic, and include urbanization, environmental degradation, market conditions, and demographic change. Though operational at local level these are influenced by national, and global socio-economic, and political structures that constrain local development opportunities, and therefore the issue of vulnerability reduction has to be addressed at three scales; local, national and international.
Approaches to vulnerability reduction include (i) implementing building codes, (ii) insurance, and social protection, (iii) emphasizing economic diversity, and resilient livelihoods, (iv) knowledge, and awareness raising, and (v) preparedness measures.
Rather than focusing only on limitations on people’s ability to reduce their risk, the policy objective of disaster risk reduction (DRR) emphasises on understanding people’s capacity to resist, and recover from disasters as well as enhancing the overall resilience of people, society, and systems. Local, and traditional disaster response knowledge of the vulnerable communities should always form the basis of external risk reduction interventions.
Development of sustainable DRR capacities requires that the capabilities be locally generated, owned, and sustained, and capacity development include not only technical capacities but also the promotion of leadership, and other managerial, and functional capacities. Capacity development at the same time requires an enabling environment that includes strong political ownership, and commitment at the highest level.