The term 'Climate change' refers to, in general, the variation in behavioral pattern of earth's climate-attributes over time (Adger, 1999). As a result of mounting concern on this issue, it has drawn the attention of researchers from different domains to study this phenomenon, and vulnerability for human created by it (Agrawala, 2008). Besides, means of humans' coping capacity in adapting to effects of climate change is emphasized by researchers. There exist an increasing number of literatures on this issue. In this chapter we construct both theoretical background and theoretical framework for this study. In this context, first we have divided the available relevant literatures into three groups in accordance with study objectives; then we go for a framework for this study. For theoretical background the first group of literatures deals with the manifestation of climate change in general; the second group deals with vulnerability concepts and dimensions; and the third group focuses on adaptation concepts in terms of capacity.
The notion of climate change sometimes possess bewildering array of terms with diversified meanings as used in different contexts by different authors. However, in this study we use the most relevant terms consistent with our research context. Therefore, the frequently used key terms for this study are- 'climate change', 'vulnerability', 'adaptation' and 'adaptive capacity.'
2.2 Theoretical background for the study
2.2.1 Key concept and literatures for first objective
There are two terms- 'climate change' and 'climate variability' used interchangeably in most cases. However, there exists a sharp distinction between them considering respective sources- the former is taken place due to various anthropogenic actions whereas the latter is due to solely natural actions. In this study we use the term 'climate change' assuming that it is the resultant of both anthropogenic and non-anthropogenic activities.
Quite interestingly, the most two notable definitions on climate change by IPCC and UNFCCC differ from each other. IPCC defines climate change as 'any change in climate overtime, whether due to natural variability or as a result of human activity' (IPCC 2007Glossary). On the other hand, climate change is defined by the UNFCCC as 'a change of climate that is attributed directly or indirectly to human activity that alters the composition of the global atmosphere and that is in addition to natural climate variability observed over comparable time periods'(IPCC 2007Glossary). To begin with a brief description of IPCC is presented along with observed and predicted results related to climate change.
The Inter Governmental Panel on Climate Change (IPCC) was established in 1988 by the World Metrological Organization (WMO) and the United Nations Environment Program (UNEP) when they notified the problem of changing trends of global climate. Their function is to assess scientific, technical and socioeconomic information relevant for the understanding of climate change. Furthermore, IPCC also deals with potential impacts of climate and options for adaptation and mitigation based on the peer reviewed and published scientific/technical literature (IPCC, 2008). Therefore, IPCC does not conduct original research, rather it releases assessment reports prepared by contributing authors that summarizes the latest findings on climate change. So far IPCC has published four assessment reports revealing the scientific information on climate change, scientific-technical-environmental-economic and social aspects of the vulnerability and mitigation to climate change. These reports discloses new findings from the previous years' research. The First Assessment Report (FAR) was released in August 1990, Second Assessment Report (SAR) in December 1995, Third Assessment Report (TAR) in 2001 and most recently Fourth Assessment Report (AR4) in 2007 (Mohamed 2008AIT). The following subsections are mainly based on the observed evidence and projected scenarios for climate change by IPCC.
Greenhouse gas (GHG) emission
These gases present in atmosphere are responsible for reducing heat-loss into space and consequently contribute in raising global temperature. High concentration of GHGs in atmosphere is supposed to absorb more solar energy re-radiated from the earth making more energy available to existing climate system. The major global anthropogenic GHGs contributing in climate change are- carbon dioxide (CO2), methane, ozone (O3) and nitrous oxide (N2O). assessment of IPCC indicate that anthropogenic GHGs are main culprits to observed climate change since industrial revolution era.
The balance of evidence suggests that there is a discernible human influence on the global climate change.
(Second Assessment Report of IPCC, 1995)
There is new and stronger evidence that most of the warming observed
over the last 50 years is attributable to human activities.
(Third Assessment Report of IPCC, 2001)
And most recently,
Several of the major greenhouse gases occur naturally but increases in their atmospheric concentrations over the last 250 years are due largely to human activities.
(Fourth Assessment Report of IPCC, 2007)
In the latest assessment report IPCC discloses that the global atmospheric concentrations of carbon dioxide and nitrous oxide have gone up remarkably due to human activities since 1975 and that fossil fuel combustion (accounting for 2/3rds of carbon dioxide) and land use change (1/3rd of carbon dioxide) are the major sources of anthropogenic carbon dioxide emission (IPCC, 2001, 2007CONTRIBUTION).
IPCC assessment report results in 2001 indicates an increase in the global average temperature, which gears up turbulence in the climatic system resulting more frequent and intense storm activity (IPCC, 2001). This report also discloses that the global average air temperature has increased by 0.6° Celsius over the 20th century. The cause of such warming has been identified as mainly to the increase of atmospheric emission of GHGs. IPCC TAR (2001) concludes that the 'most of the warming over the last 50 years is likely to have been due to the increase in GHGs concentrations' and most recently IPCC AR4 (2007) reveals that it is not likely but very likely that the most of the observed increase in global average temperature since the mid of 20th century is due to increase in anthropogenic GHGs concentrations. For the Bay of Bengal, which is a part of Indian Ocean region (The Indian ocean region in IPCC refers to the area between 35°S to 17.5°N and 50°E to 100°E), temperature is expected to increase by 2.1° Celsius for the 2050s and 3.2° Celsius for the 2080s (Nurse and Sem, 2001). The estimated projection for the low scenario is 1.8° Celsius and for the high scenario is 4.0° Celsius (IPCC, 2007).
Sea level rise
One of the most notable projected impacts of climate change is sea level rise which may induce inundation of coastal areas and low-lying islands, shoreline erosion, and destruction of important ecosystems such as wetlands and mangroves. With the increase in global temperature, sea level rise already underway is expected to accelerate due to a thermal expansion of upper layers of the ocean and melting of glaciers. Out of the many factors contributing to sea level rise, according to IPCC the most significant two causes are thermal expansion of the oceans (water expands as it warms) and the loss of land-based ice due to increased melting (the exchange of water between oceans and other reservoirs) (IPCC, 2007). The IPCC has developed different future scenarios on the possible sea level rise up to year 2100. The following figure 2.1 shows the global mean sea level in the past and as projected for the 21st century.
Fig 2.1 Estimated and projected sea-level rise
Source: IPCC, 2007
In 1990 IPCC estimated scenario for the year 2100 was a global sea level raise of 66cm with high and low estimation of 110 cm and 31 cm respectively (IPCC, 1990). In 2001, IPCC predicted a global sea level rise between 9 and 85 centimeters by 2100 and the IPCC AR4 (2007) firmly reported that global mean sea level has been rising. It reported that from observation since 1961, the average temperature of the global ocean has increased to depths of at least 3000 m and that the ocean has been absorbing more than 80% of the heat added to the climate system causing sea water to expand contributing to sea level rise. From 1961 to 2003 the average rate of sea level rise was 1.8 ± 0.5 mm per year and the average rate of 1.7 ± 0.5 mm per year for the 20th century (IPCC, 2007). Thus, IPCC concluded that the rate of sea level rise has increased between the mid 19th and the mid 20th centuries and that global sea level is projected to rise during 21st century at greater rate than during 1961 to 2003.
Extreme weather events
Climate change is being increasingly discussed in terms of extreme events and associated impacts from where a number of potential climate change effects have been identified such as- rising sea levels, changing rainfall patterns and temperature rise as mentioned above.) It is pointed that these wide range of potential impacts are likely to experienced by individuals and countries in two main ways- either as a change in average climate conditions (which is often referred to as slow onset change), or as an increase in sudden, extreme events (Tompinks et al. 2005). Examples of slow onset changes and sudden, extreme events along with its socio-economic impacts are shown in figure 2.2. The IPCC assessment reports made it clear that climate change, indeed, is happening and the observed evidence on the major causes of the change in climate, namely- GHGs emission through different anthropogenic activities has increased (IPCC, 2001, 2007). As reported by IPCC AR4 that it is very likely that hot extremes, heat waves and heavy precipitation events will continue to become frequent; and moreover, the future tropical cyclones will likely be more intense having larger peak wind speeds and more heavy precipitation associated with ongoing increased of tropical sea surface temperature (IPCC, 2007).
Extreme weather events play an important role not only in climate change issue but also in public forums regarding the impacts of global warming. The extreme climate events can be pointed out as extreme daily temperatures, extreme daily rainfall amounts, large areas experiencing unusual warm monthly temperature, or even storm events such as hurricanes (Easterling, 2000). Along with changes in average temperature, increase GHG concentrations in
Table 2.1 Observed and projected change in extreme weather and climate events by AR4 of IPCC
Phenomenon and direction of trend
Likelihood that trend occurred in late 20th century (typically post 1960)
Likelihood of future trends based on projections for 21st century
Warmer and fewer cold days and nights over most land areas
Warmer and more frequent hot days and nights over most land areas
Warm spells/heat waves. Frequency increase over most land areas
Heavy precipitation events (or proportion of total rainfall from heavy rainfalls) increase over most areas
Areas affected by droughts increases
Likely in many regions since 1970s
Intense tropical cyclone activity increase
Likely in many regions since 1970s
Increased incidence of extreme high sea levels (excluding Tsunami)
Source: IPCC, 2007
the atmosphere are likely to bring changes in climate variability and extreme events. Projected changes in extreme weather and climate events in the 21st century include more frequent heat waves, less frequent cold spells, greater intensity of heavy rainfall and greater intensity of tropical cyclones (IPCC, 2001). Tropical cyclones are predicted to be enhanced in intensity by 10 to 20% (Nurse and Sem 2001). The IPCC AR4 has referred clearly what are expected from climate change in terms of weather events, where possibility of heavy precipitation events are very likely and increase in the intensity of tropical cyclone is likely for the current century. Table 2.1 gives a clear scenario regarding various weather and climate events.
2.2.2 Key concept and literatures for second objective
The second objective of this study deals with quantitative features of vulnerability and inter-relationship between vulnerability and various socioeconomic parameters. There are a number of dimensions such as- environmental, physical, political, social etc. to define peoples' vulnerability. In this study we mainly focus on socioeconomic dimension of vulnerability of the study area.
According to the IPCC SAR-1995, Vulnerability is defined as 'the extent to which climate change may damage or harm a system; it depends not only on a system's sensitivity but also on its ability to adapt to new climatic conditions.' Sensitivity, in this case, is 'the degree to which a system will respond to a change in climatic conditions' (IPCC 1995). From this point of view, the definition of vulnerability must be contingent on estimates of the potential climate change and adaptive responses (Adger and Kelly 1999). However, in the mid-1990s the concept of vulnerability to climate change was constructed by Neil Adger in terms of physical aspect, such as- land area lost or agricultural production damaged due to extreme climate events Adger (1996). He differentiated two types of vulnerability- individual and collective on basis of key dimension in construction of vulnerability. He then defined 'Social Vulnerability' as exposure of individuals or groups to stresses from exogenous risks, especially from climatic shocks which paves the way for social marginalization.
Neil Adger again reviewed the concept of 'Vulnerability' and drew the attributes revolve round it. To him vulnerability is usually portrayed in negative notion as susceptibility of being harmed. Generally this term is applied together with environmental variation, more specifically, when climate change issues are taken into consideration (Adger, 2006). The concept 'Vulnerability' is considered as a powerful analytical tool for disclosing states of susceptibility to harm, power discrimination and marginality of both physical and social systems. However, the pattern of vulnerability may change over time and thus, challenges for vulnerability are also changed. Figure 2.2 shows how various sudden and slow events, originated from climate change, affect various factors in the society and therefore, create vulnerability.
Yamin et .al. defined vulnerability as consequence of climate change and indeed, an impediment for development process in any country Yamin et.al. (2005). The effects of climate variability manifests through floods, droughts, irregular rainfall, extreme events etc., which make the poor communities vulnerable in developing countries. Hence, these communities experience disproportionately higher levels of deaths, social discrimination and economic interruptions (Yamin et.al. (2005).
Again Vulnerability is defined by Neil Adger as an exposure of individual or collective groups to livelihood stress as a consequence of environmental variability (Adger (1999). He argued that vulnerability is often the resultant from social norms, political institutions, resource endowment, technologies and discriminations during and after a climatic shock. Therefore, the extent of vulnerability is governed by the efficiency of institutional arrangement in the concerned disaster-affected areas. From this perspective institutional context of vulnerability to climatic shocks is a pivotal element. Hence, vulnerability can be explained through a combination of social institutional factors and environmental risks. Adger also argues that vulnerability is closely associated with the notion of development, which is actually a proxy for adjustments to livelihood condition. He kept arguing that institutional inertia might affect the socio-political harmony and thus, high level of rent-seeking may jeopardize the welfare maximization; which in turn escalates the vulnerability (Adger (1999).
A study by Ibarraran et.al. shows that climate change induced vulnerability affects different localities in different ways. They emphasize on 'Resilience' to face the vulnerability while developing a Vulnerability-Resilience Indicator Model for Mexican states and picked the important resilience factors that might be useful to face the challenges of vulnerability (Ibarraran et.al. (2009)).
A new dimension of vulnerability is introduced by Barnett in terms of security problem. He explains that increasing climate change trends undermines human security by reducing peoples' access to, and quality of natural resources that are essential for sustaining livelihood. At the same time climatic catastrophes hamper the capacity of the states in providing opportunities and services to people to secure their livelihood. In many a cases there is high risk of violent conflict within the communities that eventually hampers the peace in the society (Barnett, 2007).
An alternative dimension of vulnerability is introduced by Adger and Kelly on basis of capacity. They underpin vulnerability in terms of capacity of individual and social groups to respond to i.e. coping with, recovering from and adapting to any external shocks that may affect their livelihood or well-being. In this context, resource accessibility for the groups is considered as a key determinant for vulnerability. They focus on land ownership pattern as a capacity indicator, which finally indicates the extent of resource accessibility (Adger and Kelly, 1999).
The association between climate change and vulnerability in terms of poverty is analyzed and explained in a study using a 30-years time series data, by applying GTAP (Global Trade Analysis Project) model simulation. This study shows that with the increase in climatic extreme events the agricultural productivity is hampered and as a result the prices for staple foods also go up, which in deed, enhances poverty. Therefore, the poor communities become the sufferers due to such climatic shocks. Their study results on seven socioeconomic groups in 16 developing countries showed that in short run extreme climate variations might affect the factors related with livelihood pattern of the poor people that exacerbates the vulnerability of marginal people in the communities (Ahmed (2009).
A remarkable study is conducted in Bangladesh by Brouwer et. al. where they show that households with lower income and less access to productive resources are more vulnerable in terms of climatic risk exposure. Besides, both income and asset disparity induce the households to be more exposed to various risks and thus, become more vulnerable. They also show that under the climatic shock, and with presence of income and asset disparity, individual households become more vulnerable at collective or community level since the collective level is least capable to face a common shock like cyclone or flood (Brouwer et. al. (2007).
2.2.3 Key concept and literatures for third objective
The third and last objective of this study deals with adaptation options in terms of capacity. Depending on the pattern of vulnerability, adaptation options also differs and hence, there are diversified concepts of adaptation. However, we only consider the adaptation concepts consistent with our study. According to UNFCC adaptation is a process through which societies make themselves better able to cope with an uncertain future. Thus, adapting to climate change involve
taking the right measures to reduce the negative effects of climate change by appropriate adjustments and change which includes national, local and individual level measures (UNFCCC 2009).
Considering the climate change phenomenon, the issue of response capacity is mentioned by Tompkins. As a part of risk and resource management, adaptation and mitigation actions are usually taken. By contrasting Tompkins portrayed a set of responses in national level as a trade off between development investment and new technology diffusion, and investment in enabling society to change its behavior towards new technology adoption (Tompkins, 2005).
Agrawala focused on adaptation for climate change induced vulnerability. He dealt with the potential barriers in mainstreaming adaptation. From a cross-country analysis he tried to figure out synergies and trade offs involved with integration of adaptations to climate change from the perspective of development cooperation activities, and in this way major barriers were indentified. He showed that countries more dependent on climate-sensitive natural resources are more likely to be vulnerable to climate shock. This study suggests that through better and efficient integration of climate risk management it is possible to development efforts for effective adaptation in disaster-prone areas (Agrawala 2004).
Targeting the climate change vulnerability, a community-based adaptation model is suggested by IIED (International Institute for Environment and Development). In a report IIED mention several incapability of the poor which lead them to be more vulnerable to the climate shock. Considering all these factors IIED suggest a new approach for community-based adaptation, which is a bottom-up one. The bottom-up approach is quite able to adopt the exact action/strategy required for a successful adaptation. The major international contributor like World Bank still formulates a top-down approach in this case and thus, in many regions or countries the adopted actions fail to reach the objectives (IIED, 2009).
Hubner mentions that communities respond to disasters by the strategies of- reducing consumption, drawing from savings, selling productive assets, migration, and borrowing money. But the lower income population has neither savings to utilize nor the resources to migrate. Hence, their remaining options force them to abate in both current and future consumptions. He concludes that-
There is a disconnection between large-scale surveys reporting aggregate recovery and micro-level research implying long-term reductions in consumption. If an economy recovers evenly across all income levels, then we should see no long term changes in income distribution or consumption. However, if assets are flowing from lower to higher income deciles, then we should see increased income inequality and lower consumption marked by increased volatility at lower income deciles. (Hubner, 2008)
A remarkable work on strengthening local capacity to cope with disaster (flood) is done by R. Few where he chalks out the growing tendency for interventions to prioritize strategy at the local level. Few recommended adaptation policy to challenge vulnerability, where strengthening the capacity of local people is emphasized (Few, 2003).
A theoretical perspective on institutional adaptation to social vulnerability to environmental shocks is mention by Neil Adger where institutional role in resource allocation is taken into consideration. In this work the adaptation of institutions to mediate vulnerability to climate change is observed through assessing the resource allocation and decision-making process by the institutions. In the context of economic and political transitions how effectively the coping and adaptation strategies work is examined in this study. Besides, how institutional inertia may affect coping capacity of the distressed communities is also explained (Adger, 2000).
S. Huq has worked on the classification of adaptation strategies. Side by side, he also focused on mitigation process considering on-going climate change process in the world. In the words of Huq, adaptation classifications are-
1. Anticipatory adaptation vs. reactive adaptation: Anticipatory adaptations are ones which are taken in anticipation of expected climate change impacts. Reactive adaptation occurs after the impacts have taken place.
2. Adaptation to climate change vs. adaptation to climate variability: The former refers to adaptation to anticipate human induced climate change, whereas the latter refers to adaptation to naturally occurring climate variability.
In practice, there is little difference between actions that would enhance adaptation to climate change and actions that would enhance adaptation to climate variability, but the distinction is significant in the context of funding for adaptation under the UNFCCC (which is supposed to fund the former but not the latter). (Huq, 2004)
While dealing with 'Adaptive Capacity' Huq defines it as the ability of a community or a country to adapt climate change impacts. This capacity is again decomposed into two types- generic and specific; where the former refers to inherent or existing capacity of a community as a whole to cope with climate impacts assessed through levels of income, education, development etc. of the community or country; and the latter indicates the capacity of community or country coping with climate change impacts on basis of reckoning anticipated impacts of human-induced climate change (Huq, 2004).
On the ground of mainstreaming adaptation to climate change, Huq et. al. mention the status of LDCs (group of poorest 49 countries). In this case they cited particularly Bangladesh and Mali since both of the countries made progress, although not at significant level, in introducing potential adaptation options. Nonetheless, there would remain much to be done in addressing adaptation in national level policy in terms of- relevant information on climatic risk for various stakeholders involved and policy-makers, role of civil society institutions, sharing the results of NAPA with other countries, developing international negotiation capacities and playing more active role in funding issues (Huq et al., 2004).
Social capital and collective actions are also suggested by Neil Adger as effective tools for addressing adaptation to climate change. In this case the unique feature of social capital, of possessing both public and quasi-public elements, is characterized in their role in developing bonding and networks in the society. By the dint of these social networks, communities are able to find strategies to manage climate change risks. The innate features of social capital, namely- trust, reputation, reciprocity etc. do have significant effect on social network formation through which resource accessibility in terms of property rights is ensured. Therefore, effective adaptation to climate change becomes robust once the role of social capital among communities is positive (Adger, 2003).
2.3 Theoretical framework
A major portion of this study is revolved round a Vulnerability Index. Hence, the theoretical framework is about this index and its construction. As we have already mentioned that in this study we will only deal with socioeconomic vulnerability, so the vulnerability for this study will only address the socioeconomic aspects of the study area.
We start with the idea of Pressure and Release (PAR) Model (Blaikie et al., 1994) for building a concept for vulnerability index. This PAR model is applicable for disaster led vulnerability. The core theme of this model is that a disaster is the intersection of two opposing forces: the process generating vulnerability from one side, and the physical exposure to hazard from the other. Increasing pressure can come from either side, however, vulnerability has to be reduced to relieve the pressure (Anon, 2008). Vulnerability is considered in three levels- root causes, dynamic pressures and unsafe conditions. The pros of this model are that it provides a possible complete view of vulnerability, it emphasizes the natural hazards and it gives a framework for inspecting vulnerability and livelihood (Anon, 2008). However, this model can not measure vulnerability; and without collecting and analyzing a great of data this model can not be operationalized (Anon, 2008).
2.3.1 Model framework for this study
In this study we have adopted a Composite Indicator Framework Method, which is originally developed as Community-based Risk Index (Bollin and Hidajat, 2006). This method is used to assess vulnerability at local/community level and it resemblances with basic features of PAR model. We adopt this method from a UNU (United Nations University) book edited by Joern Birkmann in 2006.
The Community-based Risk Index basically aims to identify and quantify the main risk factors like- exposure, vulnerability, management capacity etc. within a community (Birkmann, 2007). With the help of this index it is possible to compare risk-exposure levels between communities. At the same time it is also possible to figure out if this risk-exposure is an outcome of any hazard or natural disaster or vulnerability or capacity component (Bollin and Hidajat, 2006). Hence, this index consists of four basic components- hazards, exposure, vulnerability and capacity measure. There are a total of 47 indicators in this index which are further divided into factor-components/variables (Birkmann, 2007). The approaches used in this index can serve as important tool to identify and highlight the areas where both risk and vulnerability reduction are needed. Hence, this index provides comparative information on many aspects of disaster risk and vulnerability (Birkmann, 2007). However, there are some questions regarding the aggregation and choices for indicators under this index, which seem to be redundant to some extent and therefore, vulnerability and risk identification might not be accurate in all instances (Birkmann, 2007).
Since our main concern in this study is with vulnerability, we have adopted only the 'Vulnerability' component from this Community-based Risk Index. In original index, the vulnerability component is decomposed into four different thematic premises- physical, social, economic and environmental (Bollin and Hidajat, 2006). However, in this study we have modified the 'environmental' theme into 'disaster-exposure' and we have included 'demographic' as a new thematic area. We modify the original index in order to maintain relevance and applicability with the features/characteristics of our study area. Therefore, the modified approach in this study to identify vulnerability in numerical values consists of five thematic premises. We will define these premises as 'Vulnerability Domains,' and the new index as 'Vulnerability Index' in the following chapters. For each domain we select a number of relevant variables (see detail in Appendix I).
The literatures under theoretical background have chalked out the likelihood of climate change and its associated consequences on coastal areas and low-lying islands. Several authors have mentioned the vulnerability of Bangladesh to climate change. Due to unfavorable socioeconomic conditions the coastal people of Bangladesh are challenged with predicted sea-level rise, cyclone with storm surge and other consequences of climate change. From this perspective, vulnerability of these coastal people, in both household and community levels, and their coping capacity are important issues requiring urgent attention. Literatures also indicate the importance of adaptation and adaptive capacity in the coastal areas. In the next chapters we will see how our empirical findings comply with the issues addressed in the theoretical background. We are also interested to see the same in case of the theoretical framework for this study.