Forest Service Rocky Mountain Research Station General Technical Report RMRS-GTR-328 July 2015

United States Department of Agriculture

Key Concepts and Methods in Social 

Vulnerability and Adaptive Capacity

Daniel J. Murphy

Carina Wyborn

Laurie Yung

Daniel R. Williams
Murphy, Daniel J.; Wyborn, Carina; Yung, Laurie; Williams, Daniel R. 2015. Key concepts and 

methods in social vulnerability and adaptive capacity. Gen. Tech. Rep. RMRS-GTR-328. Fort 

Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. 24 p.

Abstract

National forests have been asked to assess how climate change will impact nearby human communities. To assist their thinking on this topic, we examine the concepts of social vulnerability and 

adaptive capacity with an emphasis on a range of theoretical and methodological approaches. This 

analysis is designed to help researchers and decision-makers select appropriate research approaches 

suited to particular planning and management needs. We first explore key conceptual frameworks 

and theoretical divisions, including different definitions of vulnerability and adaptive capacity. We then 

focus on the different methods that have been used to assess vulnerability and adaptive capacity 

and their respective pros and cons. Finally, we present and discuss three case examples and their 

respective research approaches.

Keywords: climate change, adaptation, vulnerability, adaptive capacity.

Authors

Daniel J. Murphy is an Assistant Professor of Anthropology at University of Cincinnati. 

Carina Wyborn is a Postdoctoral Research Fellow in the Department of Society and Conservation 

at the University of Montana. 

Laurie Yung is an Associate Professor of Natural Resource Social Science in the Department of 

Society and Conservation at the University of Montana. 

Daniel R. Williams is a Research Social Scientist at the USDA Forest Service, Rocky Mountain 

Research Station.
Contents

Introduction .............................................................................................................. 1

Framing, Understanding, and Approaching Social Vulnerability and 

Adaptive Capacity ............................................................................................... 2

Conceptual Frameworks ......................................................................................... 6

Actor-Oriented Versus Systems-Oriented Approaches ................................ 6

Actor-Oriented Approaches to Social Vulnerability ....................................... 7

Systems-Oriented Approaches to Social Vulnerability ................................. 9

Outcome-Oriented Versus Contextual Frameworks ................................... 10

Outcome Approaches to Social Vulnerability .............................................. 10

Contextual Approaches to Social Vulnerability ............................................11

Summary .................................................................................................... 12

Assessments and Methodologies........................................................................ 14

Dose-Response .......................................................................................... 16

Indices and Indicators ................................................................................. 17

Case Studies .............................................................................................. 18

Scenario Processes .................................................................................... 19

Participatory Approaches ............................................................................ 20

Conclusion ............................................................................................................. 21

References ............................................................................................................. 22

USDA Forest Service Gen. Tech. Rep. RMRS-GTR-328. 2015 1

Introduction _____________________________________

Communities1 in North America face myriad ecological and socioeconomic changes 

due to climate change. These communities are already coping with and adapting to 

changes such as prolonged drought, insect and disease outbreaks, changing fire regimes, and extreme weather events. Further, climate change impacts are expected to 

worsen in coming decades. Human communities in close proximity to national forests, 

parks, or other public lands enjoy ecosystem services, natural resources, and recreation 

opportunities from these lands. For these communities, the local impacts of climate 

change have a range of negative consequences, such as affecting the ability to water 

crops, exacerbating fire risk and smoke levels in the wildland-urban interface (WUI), 

undermining the viability of local timber mills, and limiting winter tourism operations 

(Figure 1). Additionally, not only are these communities vulnerable to climate change 

impacts, but vulnerable groups within these communities might also bear a disproportionate burden from climate change.

National forests have complex and important relationships with nearby communities. 

For example, many communities depend on local national forests for timber supply, 

tourism ventures, hunting opportunities, recreation and leisure, aesthetic enjoyment, 

and water resources. In addition, community members have meaningful cultural, social, 

personal, and spiritual relationships with national forest lands. Climate change impacts 

on national forest lands will undoubtedly affect these relationships. Consequently, adjacent communities will be invested in, and impacted by, the adaptation actions national 

forests take in response to the local effects of climate change.

For that reason, Forest Service leadership has identified the need for vulnerability 

assessments of human communities near and/or dependent upon national forests. The 

Forest Service Climate Change Performance Scorecard includes an important item on 

community vulnerability (what we call “social vulnerability” throughout this report). 

1 We define communities here as human communities who are affected by management of national forests 

and other public lands. These are typically rural communities near or adjacent to public lands, communities 

with a history of natural resource-oriented economic activity, ranging from timber and grazing to outfitting 

and restoration. These communities are situated in a range of ecosystems, including forests, grasslands, 

deserts, and coastal systems. The WUI is often an important component of these communities. In some 

cases, urban communities are also affected by public lands management.

Figure 1—The Town of Winter Park, Colorado, is highly dependent 

upon winter snowpack to support its economy. Photograph by 

Daniel R. Williams.
2 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-328. 2015

As a result, national forests need effective methods and tools for completing social 

vulnerability assessments. Alongside improved social vulnerability assessments, there 

is also a need for an improved understanding of adaptive capacity (and its relationship 

with vulnerability) and how communities might increase their adaptive capacity in the 

face of climate change. Pairing assessment of vulnerability with attention to improved 

adaptive capacity provides both a realistic picture of threats as well as possible paths 

toward community action and empowerment. Assessments of social vulnerability, especially when integrated with assessments of biophysical vulnerability, can help national 

forests understand how the local ecological effects of climate change are impacting 

nearby communities and their relationships with forest resources. These assessments can 

also assist national forests in formulating management actions that limit these impacts, 

wherever possible.

Recent publications have reviewed social vulnerability (e.g., see Lynn and others 

2011) and some of the approaches to measuring it (e.g. see Fischer and others 2013). 

This report builds on and deepens those efforts through a theoretical and methodological 

analysis designed to guide researchers and decision-makers in selecting appropriate approaches suited to particular planning and management needs at different scales of land 

management. The following review examines some of the key concepts and methods 

in vulnerability and adaptive capacity. Drawing from a growing research literature, the 

Framing, Understanding, and Approaching Social Vulnerability and Adaptive Capacity 

section of this report explores key conceptual frameworks and theoretical divisions in 

this field. In this section, we discuss the different definitions of vulnerability and adaptive capacity. The Assessments and Methodologies section of the report focuses on the 

different methods that have been used to assess vulnerability and adaptive capacity 

and their respective pros and cons. This publication is intended to canvas the disciplinary diversity present in the field and to highlight why researchers, policy-makers, and 

practitioners should understand and be able to articulate these differences. Our goal is 

to demonstrate how theoretical and conceptual frameworks impact choices about methods and how methods respond to particular kinds of data needs. Ultimately, we hope to 

encourage both scientists and practitioners to be more explicit in the choices they make 

about what research to do and use through articulating the diverse frameworks used to 

think about or conduct social vulnerability assessments or research on adaptive capacity.

Framing, Understanding, and Approaching Social 

Vulnerability and Adaptive Capacity _________________

Social vulnerability has a long history in a number of fields. Research into the impacts 

of hazards has examined the vulnerability of different groups in relation to events such 

as earthquakes and floods for many decades. In contemporary climate change research, 

definitions of vulnerability and adaptive capacity are more variable. Climate change 

introduces a level of uncertainty and spatial pervasiveness that challenges the traditional 

view of hazards as containing distinct phases: (1) pre-event, (2) event, and (3) post-event 

or distinct impact zones such as a “landfall site” or “epicenter.” In contrast, climate 

change impacts are long-term, multi-scale, and widely distributed, though potentially 

uneven across time and space.

With this in mind, the Intergovernmental Panel on Climate Change (IPCC) has defined 

vulnerability as “the degree to which a system is susceptible to, or unable to cope with, 

adverse effects of climate change, including variability and extremes. Vulnerability is a 

function of the character, magnitude, and rate of climate variation to which a system is 

exposed, its sensitivity, and its adaptive capacity” (McCarthy and others 2001:21). In this 
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-328. 2015 3

influential definition, exposure refers to the proximity of units or systems to disturbances 

resulting from climatic variation and sensitivity refers to the susceptibility of potential 

loss from these impacts. Adaptive capacity is defined as an element of vulnerability 

that includes “the characteristics of communities, countries, and regions that influence 

their propensity or ability to adapt” (McCarthy and others 2001:18, emphasis added). 

These definitions are often represented in the formula:

Exposure + Sensitivity + Adaptive Capacity = Vulnerability

The definition and representation of vulnerability in this formula has significantly 

influenced the design of vulnerability assessments as it forces us to consider how different factors contribute to vulnerability. However, as recognized in the most recent IPCC 

report (2014), conceptualizing vulnerability in this simple linear formula neglects the 

broader social, political, and economic forces shaping how a community is affected by 

natural disturbance. Further, the three terms in the formula often lack clear definitions, 

and their definitions differ across fields and disciplines (Hinkel 2011).

Different definitions and conceptual frameworks shape how vulnerability and adaptive capacity are understood and examined. For example, some describe vulnerability 

as a state of powerlessness (Hewitt 1997) or the presence of unsafe conditions (Wisner 

and others 2004), while others see vulnerability simply as an exposure to some external 

natural phenomenon. Viewing vulnerability as a function of exposure to natural phenomenon directs the research lens to examine the extent, magnitude, and probability 

of different climate-based hazards. In contrast, viewing vulnerability as a state of powerlessness directs attention to the broader socio-political structures and processes that 

shape the distribution of impact across society. For example, vulnerability to drought 

could be viewed as the condition of a community being located in an area where there 

is a regional absence of precipitation or as a function of access to water resources. The 

former frames drought as a purely biophysical process while the later focuses on the 

socio-political processes that determine water rights and distribution. Different ways of 

conceptualizing vulnerability also raise different ethical questions (see Box 1).

A key element of vulnerability is adaptive capacity—a much more difficult and 

complex concept to define. Adaptive capacity focuses on the capacity of individuals, 

social groups, and organizations to pursue adaptation. Adaptive capacity is related to 

the availability and distribution of knowledge, resources and technology, management 

and decision-making processes, regulations and policies, levels of social and human 

capital, and perceptions of risk and individual or collective ability to influence change 

(Yohe and Tol 2002; O’Brien and Hochachka 2010). The adaptive capacity of a community is a combination of characteristics that are internal to an individual, community, 

or organization and external factors that are beyond their control that either enable or 

constrain their ability to respond to change. For example, a community may have the 

resources and shared motivation to store more water in the landscape in stock ponds or 

reservoirs in order to provide a buffer against drought. However, without water rights, 

they may be unable to build on their capacity to undertake adaptation.

In thinking about adaptation and adaptive capacity, the principal questions concern 

what is adapting, to what and why, and where does the capacity to adapt come from (Smit 

and others 2000). Adaptive actions respond to different needs at different scales (e.g., 

individual, community, region, and nation), and such actions are shaped by capacities 

at those scales. Climate change is one of many drivers influencing the decisions of 

communities and individuals, and it can be difficult to separate out a singular driver 

of change from the complex and multi-scalar forces shaping landscapes and communities. 
4 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-328. 2015

Box 1: Implications of Scale for Vulnerability Assessments

Scale is an issue that receives significant attention in the literature focused on vulnerability and adaptive capacity. Many researchers recognize that the processes driving both 

vulnerability in the broad sense and, specifically, the component of adaptive capacity are 

often removed—spatially, temporally, or politically—from an affected area or population 

(Smit and Wandel 2006; Adger and others 2009). In a globalized world, virtually all social, 

ecological, economic, or cultural systems have external drivers at different scales and levels. Thus, it is critical to understand the multi-scalar dimensions driving vulnerability and 

adaptive capacity. 

In the search for determinants and indicators of adaptive capacity, a growing critique has 

emerged arguing that indicators will differ depending on the scale of the adaptive unit being 

analyzed (Wilbanks and Kates 1999; Adger and Vincent 2005; Vincent 2007). For instance, 

the characteristics of adaptive capacity within households will be significantly different 

than those for communities or for countries (Adger and Vincent 2005; Vincent 2007) and 

for individuals (Grothman and Patt 2005). Yet, these forms of social organization are also 

nested, as nation-states consist of and govern communities and households, and communities are embedded in nation-states (Adger and others 2009). 

Consequently, the scale issue is more critical than simply selecting some kind of exposure; rather, the issues concern: (1) how exposure units are implicated at various scales, and 

(2) how the scalar nature of the unit is produced. Both vulnerability and adaptive capacity 

depend on a variety of social, political, economic, technological, and institutional factors 

whose interactions differ depending on the scale of analysis (Vincent 2007). At a national 

scale, adaptive capacity is not only a function of the availability of resources but also the 

ability to direct resources to areas of greatest need. At a household level, more common 

drivers are the knowledge base of an individual, the availability of alternative livelihoods, or 

access to resources. As these factors interact across scales, vulnerability assessments need to 

account for cross-spatial and cross-scalar processes and outcomes (Eakin and Luers 2006). 

In practice, this entails understanding the factors driving vulnerability that may not be 

obvious at the site of concern. For example, the water flowing through a particular county, 

community, or watershed may seem sufficient for the population and land use in the area. 

However, if non-local entities (landowners, urban centers, etc.) own water rights to local 

water, the water available to local communities may be insufficient. Only through understanding the broader regulatory context within which water is governed can a complete 

picture of useable water be found. Likewise, scales of adaptive capacity are interdependent: 

a household’s capacity to cope is, to a certain extent, mediated by the adaptive capacity 

of the community and the regional availability of resources (Yohe and Tol 2002; Smit and 

Wandel 2006). Contextual approaches to vulnerability are more likely to pay attention to 

scale, as these approaches are concerned with identifying how broader socio-political and 

economic forces shape vulnerability.

Understanding forces and processes at non-local scales requires a methodological approach 

that recognizes and examines factors that occur at multiple scales (Wilbanks and Kates 1999; 

Gibson and others 2000). Further, it is important to recognize that macro-scale processes 

are fundamentally different from those operating at a smaller scale. An adaptation program 

designed for a small and relatively uniform community is unlikely to be readily transferred 

to a regional center with a diverse population and a broader income base.
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-328. 2015 5

This also brings in the question of whether adaptation is a process of structural change 

in response to external stressors or a state of adaptedness in which the structural characteristics of a system are effective in dealing with its environment (Young and Lipton 

2006, emphasis added). In some cases, climate change impacts may be so significant that 

existing industries, such as flyfishing tourism, or infrastructures, such as fire suppression 

resources, are no longer viable. Such circumstances may require structural changes involving 

changes to land use or reconfiguring the ways that decisions are made. In contrast, a state of 

adaptedness exists when decision-making processes or industries are configured to enable 

responses to changes in climate. Smit and others (2000) also pointed out that adaptations 

can be anticipatory (anticipating future change) or reactive (reacting to current or immediate 

threats), autonomous (pursued by individuals) or planned (pursued by organizations, communities, or governments). Some researchers explore adaptive capacity in reference only 

to specific events, risks, or thresholds, while others are more concerned with what might 

be a called a generic capacity to adapt (a broad capacity to adapt to many different kinds of 

changes) (Lemos and others 2013).

A significant portion of the literature on adaptive capacity is concerned not so much 

with adaptation or capacity in any theoretical sense, but with adaptive actions. Thus, 

vulnerability is often seen as the lack of such action or capacity to engage in adaptive 

actions. To be adaptive is to alter the direction of management in response to social, 

political, or ecological changes. For example, changes in spring green up may impact 

the timing of forage availability on the range. An adaptive action in response to this 

change might be to alter the start date for a grazing allotment. Nelson and others (2007) 

and Smit and Wandel (2006) explained the difference between coping and adaptation. 

Coping action tends to be used to describe shorter-term adjustments made to simply 

survive a disturbance, whereas adaptive actions describe longer-term, more sustainable adjustments. Coping actions are not adaptive in the sense that they do not support 

transformative change, that is, complete reorganization or transformation of current 

management. Figure 2 graphically represents the coping range, demonstrating the range 

of variability under which coping strategies may provide a buffer against change. However, coping ranges and adaptive capacity are not static; steps can be taken to increase 

the coping range, or conversely, decisions can erode a coping range (Smit and Wandel 

2006). For example, a rancher might cope with drought by reducing herd size. However, 

switching to a drought-tolerant cattle breed might improve the ability to deal with future 

droughts, thereby increasing the coping range.

Figure 2—Smit and Wandel (2006) depicted the way in which coping range 

expands as adaptive capacity grows.
6 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-328. 2015

Coping often focuses on the actions individuals or communities have taken in the past 

in response to a specific change or hazard. However, the usefulness of past responses 

in future adaptations is uncertain, as climate change may lead to fundamentally new 

conditions compared with those in the past. When a system is undergoing large-scale 

changes that exceed functional thresholds, coping is no longer effective; rather, the 

system and system elements must adapt to novel conditions. For example, a community might suppress a wildfire to cope with threats to life and property. But, in the 

longer-term, suppression increases fuel levels, which may result in more intense, larger 

fires in the future and more difficulty suppressing such fires. An adaptive action could 

involve enabling fires to burn in areas where there is no threat to life and property, 

while a transformative action could be to reconsider the patterns of development in 

the WUI. Similarly, a local mill facing a timber shortage may truck in raw logs from 

far away forests to remain productive. But, after a number of years, the added expense 

may decrease their competitiveness and result in closure. This type of action is known 

as maladaptation, whereby the adaptive response simply delays the onset of a larger 

problem or creates feedbacks that further exacerbate the problem. While not always 

possible, maladaptive responses can be avoided by thinking through and assessing the 

causal drivers of change and assessing these factors during adaptation planning. In the 

prior example, an adaptive or even transformative response might be to retool the mill 

to focus on the small diameter timber being harvested to reduce fuel levels.

Conceptual Frameworks ___________________________

Underlying these broad definitions are different conceptual frameworks that focus 

attention on different elements of vulnerability and adaptive capacity. A conceptual 

framework is an analytical tool used to organize ideas and communicate the theoretical 

logic behind a way of viewing the world. It is important to understand the conceptual 

frameworks behind interpretations of vulnerability and adaptive capacity because they 

focus attention on different elements of a problem, and lead to different research questions, new knowledge, and concomitant management or policy responses. We identified 

four key conceptual frameworks within the literature: actor-oriented, systems-oriented, 

outcome-oriented, and context-oriented. Our intention in laying out these different 

frameworks is to illustrate the diversity of conceptual and methodological approaches 

adopted in studies of vulnerability and adaptive capacity.

To illuminate some of the differences among these approaches, we will describe 

the key concepts and frameworks presented in Table 1. These conceptual frameworks 

lend themselves to different assessment approaches and methodologies, which will 

be discussed in the Assessments and Methodologies section. Surveying the array of 

approaches and methodologies is a critical and necessary step prior to undertaking an 

assessment of vulnerability and/or adaptive capacity. Understanding the goals and focus 

of an assessment, the nature of the available data, and the strengths and weakness of 

different approaches will ultimately lead to a more useable project tailored to specific 

needs and context.

Actor-Oriented Versus Systems-Oriented Approaches

To begin, we explore a distinction highlighted by Nelson and others (2007) between 

actor-oriented and systems-oriented research. We then discuss the difference between 

outcome-focused and contextual-based conceptual frameworks before moving on to 

survey a range of different assessments and methodologies utilized to assess vulnerability and adaptive capacity.
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-328. 2015 7

Actor-Oriented Approaches to Social Vulnerability

Actor-oriented perspectives focus on discernible exposure and/or adaptive units such 

as countries, communities, households, and individuals or on specific attributes of units 

such as wellbeing, livelihood, or health. These approaches assume that actors (individuals or groups/collectives) have agency and can influence and shape the world around 

them. There are two bodies of actor-oriented research: (1) rational choice approaches, 

and (2) relational approaches. These approaches seek to understand how vulnerability 

is produced through a broader set of interactions in which actors and exposed units are 

situated.

The rational choice approach focuses on constraints and opportunities only in the way 

they impact an actor’s decision-making processes. For example, Yohe and Tol (2002) 

included the following:

1. the range of available technological options,

2. the availability of resources and distribution,

3. the structure of institutions,

4. stocks of human and social capital,

5. access to risk-spreading mechanisms,

6. ability of decision-makers to deal with risk and information,

7. the public’s perception, and

8. the significance of exposure.

Table 1—Key conceptual frameworks in social vulnerability and adaptive capacity.

Framework Focus Goal Key concepts Pros Cons

Actor- Exposure units Outline constraints Rational choice Combines context- Overly specific.

oriented and courses of and opportunities for approach focuses orientation and Can miss

action. specific actors, their on decision-making. outcome-orientation. structural

decisions, and their Relational approach Applicable at multiple dynamics.

actions focuses on context spatial scales and with

(see Context-oriented). various exposure units.

Systems- Exposure and Outline functional Coupled human-natural Focuses on Too abstract. 

oriented resilience of relationships and systems involving relationships. Terms are

relationships dynamic response feedbacks and linkages. Concerned with ambiguously

that make up to change. Resilience: adapting transformative defined.

systems. while retaining function. change.

Resistance: averting 

change. Thresholds: 

transformative change. 

Outcome- Impacts of Demonstrate causal Hazards-based approach, Targeted and narrow Misses important

oriented objective relationship focuses on exposure units with discrete variables dynamics. Can be

threats on between hazard and impacts. Vulnerability Comparative. Easily reductionist,

discrete and loss. is a function of impact and applied. Uses existing decontextualized,

exposure exposure. data. and aprocessual.

units. 

Context- The spatial and Demonstrate the Political economy More accurately Lack of agency.

oriented temporal scales complexity of (institutions, policies, reflects reality. Lack of scaling 

that produce vulnerability and etc.). Moral economy Broader vision of up. Overly

constraints and adaptation. (values, perceptions, etc.). drivers of change. specific.

opportunities. 
8 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-328. 2015

Actors in this approach are treated as largely autonomous from society and broad 

social structures and, therefore, are seen as independent navigators of a landscape of 

options and barriers. Pelling (2010) argued that “too often th[is] literature reduces the 

individual to a rational economic actor” and misses the broader social forces and conditions that turn people into exposure units.

In relational approaches, vulnerabilities and adaptations are a result of relationships: 

(1) between exposed units (or the relationships that sustain these units) and stressors, 

and (2) between those units and relationships with social forces at local and non-local 

scales. Relational approaches see the world as a series of interactions among actors, 

institutions, and contexts, whereby the interactions between entities change their identity. 

Relational perspectives focus on how vulnerability, adaptive capacity, and adaptation 

co-evolve through the interactions among social and political institutions, communities, 

and economies. Accordingly, understanding the relationships and interactions among 

individuals, communities, institutions, and policies, as well as their relationships with 

climate-driven stressors such as drought or forest insects is key to understanding social 

vulnerability (Figure 3).

A relational approach also requires a focus on the informal and formal networks, 

institutions, and organizations that constitute social relationships through ethics and 

morals, social norms, formal policies, and cultural forces. Relational analyses examine 

the integration of actors, and the structure of relationships in both horizontal (i.e., local) 

and vertical (i.e., non-local) networks (Ingold and others 2010). In relational approaches 

to vulnerability and adaptation, interactions or relationships across scales are particularly important (Rodima-Taylor 2012). For example, in order to effectively evaluate a 

community’s vulnerability, one must consider the relationship between the community 

and public agencies such as the Forest Service and how they affect one another. The 

adaptive capacity of communities with antagonistic relations with public agencies will 

be very different from those with more agreeable relations. A relational approach would 

inquire into how these different relationships shape, enable, or constrain vulnerability 

and adaptive capacity.

Figure 3—Beaver slide, which is used for stacking 

hay, dot the landscape in the Big Hole, Montana. 

The slides are indicators of both the viability of 

ranching as a livelihood, as well as ranching’s 

place in the Big Hole community identity. Photo 

by USDA-NCRS.
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-328. 2015 9

Systems-Oriented Approaches to Social Vulnerability

Not all researchers are concerned specifically with exposure units. Instead, some research focuses on the vulnerability and adaptive capacity of systems. Much of this work 

draws on the social-ecological systems literature that attempts to conceptually couple 

human and natural systems (Gunderson and Holling 2002; Berkes 2007). Central to 

this framework are the notions of feedbacks, linkages, and resilience. Feedbacks refer 

to processes that reinforce or modify the behavior of a system—for example, the way 

forests respond to fire, or how a community changes behavior in response to a fire event. 

Systems approaches use the concept of linkages to refer to the connections or points 

of interactions between different elements of a system, such as the way management 

and forest communities are partially integrated, or the relationship between fish stocks 

and quotas for fishing in a marine system. Resilience refers to the ability of a system to 

undergo change while maintaining the capacity to retain, re-organize, or regain the same 

structure and function prior to disturbance. These concepts illustrate the dynamic and 

relational dimensions of adaptive capacity and vulnerability as they direct attention to 

the interactions among aspects of a system and how they change over time. The focus 

on linkages and feedbacks within social-ecological systems highlights how vulnerability 

can emerge from social or ecological processes and the interconnections between these 

two domains (Nelson and others 2007).

Conceptualizing the vulnerability of systems rather than exposure units changes how 

we think about exposure, sensitivity, and other aspects of vulnerability. According to 

a systems approach, exposure units can only be conceived in their relations and not as 

independent, discrete entities (note the overlap with the relational approach previously 

discussed). Systems perspectives point to the importance of attending to thresholds, which 

represent the boundaries around which a system remains in a particular state (Nelson 

and others 2007). For instance, when a relationship between units is exposed to a hazardous threat, there is, at some level, a threshold point beyond which that relationship 

is no longer functionally possible within novel conditions. For example, if a ski resort 

community no longer gets enough snow to maintain operations, a local economy built 

around winter recreation may not be possible. Thinking about vulnerability and adaptive capacity in this way is critical because climate change poses such transformative 

threats to various social-ecological systems around the globe.

The focus of a systems-oriented approach continues to center on exposed units with 

“units” contextualized within broader systems (or even with systems as exposure units). 

Problematically, much of this work also continues to conceptually divorce social systems 

from natural ones. For instance, climate change is often positioned as an external threat 

to the system rather than as a system-generated disturbance. This is an important point 

because what is included or excluded from the definition of the system can shape how 

we think of vulnerability and adaptive capacity. Moreover, a systems approach so far 

has also encountered significant difficulties in dealing with issues of social or political 

power and may overlook the fact that different individuals, communities, and organizations have unequal abilities to act and adapt to change (Davidson 2010; Thornton and 

Manasfi 2010).

Researchers have highlighted two possible adaptive responses: resistance or resilience. 

Resistance focuses on efforts to resist the local effects of climate change or delay the 

impacts (e.g., by maintaining or investing in existing system relationships, including current practices, livelihoods, and institutions). Resilience focuses on adapting in ways that 

preserve functionality through new system relationships that can better weather change 

(e.g., local livelihoods are possible but might shift to new sectors; water is available 

for irrigation but practices change; and timber is harvested but better adapted species 

are replanted). In the context of forest communities, resistance might entail replanting 

species that have historically been present due to their value for timber production, even 
10 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-328. 2015

though such species do not thrive under predicted future conditions such as drought. In 

contrast, if such a community accepted system transformation, they might pursue tree 

species with commercial value that are predicted to do well under future conditions. 

Another example of an adaptation that increases resilience by embracing transformation is to establish water conservation measures to meet the needs of water users under 

future precipitation scenarios.

Outcome-Oriented Versus Contextual Frameworks

As recognized in the most recent IPCC report (2014), another key difference in how 

vulnerability is conceptualized revolves around the focus on either outcomes or process. 

O’Brien and others (2007) argued that there is a distinction between an outcome approach, 

which is focused solely on actual losses, and a contextual approach, which is focused 

on the conditions, processes, and contextual dynamics that enable loss. Figure 4 depicts 

the differences between outcome and context-oriented approaches to vulnerability. In 

particular, outcome-oriented approaches are more linear and narrowly frame vulnerability 

as a function of climate impacts on exposed units, whereas contextual approaches focus 

on a multitude of social, political, economic, institutional, and biophysical conditions 

that, through their interactions, produce vulnerability.

Outcome Approaches to Social Vulnerability

Outcome approaches tend to follow along two lines: starting point and end point 

research (O’Brien and others 2007). Starting point assessments begin by identifying sensitivity (the susceptibility to potential impacts) to exposure (the magnitude of 

the impact) in relation to a community’s capacity to respond to stress. Accordingly, 

vulnerability is envisioned as a condition inherent in certain populations. While this is 

similar to the actor- and system-oriented approaches, in an outcome-oriented approach, 

the focus is on the populations themselves rather than the broader system in which 

they are situated. The assumption is that certain characteristics, such as poverty, lack 

Figure 4—Distinctions between outcome vulnerability and contextual vulnerability (from O’Brien and others 2007).
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-328. 2015 11

of education, or minority status, make certain groups inherently more vulnerable to the 

impacts of climate change (see Lynn and others 2011 for a detailed discussion of how 

demographic characteristics influence social vulnerability). The strength of this research 

is that it enables a rapid assessment of sensitivity, or the differential or uneven impacts 

of climate change on human communities. That said, sensitivity is seen largely as a fixed 

characteristic or set of attributes rather than as dynamic and emerging from a complex 

context that produces both vulnerability and adaptive capacity. In contrast, end point 

assessments focus on exposure. Future vulnerability is assessed in response to a specific 

event. Analysis begins with projections of future emissions trends, which are then used 

to understand biophysical impacts and the susceptibility of different regions, groups, 

or sectors to specific losses generated by those impacts. Both starting point and end 

point approaches see vulnerability as an outcome of a climate stressor on a vulnerable 

population rather than the broader contextual approaches that consider vulnerability to 

be a function of a broader array of processes.

Accordingly, vulnerability is seen largely as exposure to an objective threat, such as 

sea level rise, increased fire frequency, or reduced winter snowpack. Adaptive capacity, the ability to adapt to such threats, is viewed as the inverse of vulnerability. These 

studies quantify loss potential, sectoral impacts, and appropriateness of technological 

adaptations (O’Brien and others 2007). For example, research might examine the impact 

of temperature change on forage and livestock production in rangelands. A number of 

assumptions underlie this perspective. First, exposure/adaptive units are easily identifiable and experience discrete impacts. Secondly, since much of this research utilizes a 

dose-response methodology (see the Dose-Response section), the exposure/adaptive 

unit is taken as an independent variable and is divorced from contextual dynamics. For 

example, the response of individual households to forest fire is examined independent 

of fire ecology, local fuel reduction efforts, national fire policy, and agency capacity 

to manage fire. In adaptive capacity research, similar frameworks compare exposure/

adaptive units in order to understand why losses did not occur. Outcome research, both 

starting and end point approaches, have been criticized for not considering politics, context, and process because research in this arena sometimes avoids the vast complexities 

that produce and sustain vulnerabilities, adaptive capacity, and adaptations.

Contextual Approaches to Social Vulnerability

Contextual approaches envision vulnerability and adaptive capacity as highly 

contextualized within social, political, economic, and ecological contexts at multiple 

scales from local to global. In particular, a contextual approach examines institutional 

constraints, social and economic barriers, and underlying historical processes and the 

differential capacities and sensitivities these induce. Context-oriented research is more 

complex in its considerations than outcome-oriented approaches, examining the various 

ways that vulnerability and adaptation are constrained or enabled (largely reflecting the 

list by Yohe and Tol 2002).

As such, contextual approaches typically consider governance issues (Adger and 

others 2009). At the community level, adaptation measures must take into account 

the will of local citizens, nongovernmental organizations, and local governing bodies. 

Wall and Marzall (2006) and Zarhan and others (2008) highlighted the ways in which 

governance influences the relevance, credibility, and legitimacy of different actions to 

local communities that are seen as critical to formulating potential course(s) of action. 

A number of works have also highlighted the importance of top-down governance issues in shaping adaptive actions at the local scale (Eakin and Lemos 2006; Pahl-Wostl 

2009). In the case of national forests, both top-down federal policies and initiatives and 

local community- and Forest-level governance will need to be considered when thinking 

about social vulnerability.
12 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-328. 2015

Contextual approaches also consider the social, psychological, and cultural limits to 

adaptation (Crate and Nuttall 2009; Hulme 2009; Norgaard 2011). For example, climate 

change perceptions and beliefs influence the possibility for action. These kinds of perceptions are also implicated in how individuals, communities, and societies view risk and 

thus vulnerability (Shackley and Deanwood 2002; Tucker and others 2010). For example, 

people’s beliefs about climate change may influence whether or not they see projected 

changes to in-stream flow and native fisheries as problematic, and how they describe 

the vulnerability of local fishing outfitters to climate change. Interest in and motivation 

to adapt is influenced by values, interests, and political ideologies (Adger 2006; Roberts 

and Parks 2006). For example, when local changes are viewed as part of natural variability (a common view among climate skeptics), the need for adaptive actions may not 

be considered important as this perspective assumes that changing conditions, such as 

water shortages, are only temporary. In contrast, when local changes are viewed as part 

of a longer trend (i.e., climate change), adaptive actions may be viewed as a priority.

Contextual approaches also examine the way society and its members learn and the 

connections between that learning process and subsequent action (Pelling and others 

2008; Tschakert and Dietrich 2010; Krasny and others 2011). Experimentation, imitation, communication, and reflection are seen as critical elements in somewhat nebulous 

networks of learning and knowledge production that fill in the spaces between formal 

institutions (Berkhout and others 2006; Krasny and others 2011). Thus, the informal 

networks within forest communities and the capacity of such networks to learn from 

and respond to local changes, such as beetle outbreaks, floods, or fire, are an important 

component of adaptive capacity.

Lastly, contextual approaches explore the ways that local adaptive capacity and vulnerability are connected to global processes. As Adger and others (2009:150) pointed 

out, the “vulnerability of specific individuals and communities is not geographically 

bounded but rather is connected at different scales, so that the drivers of their exposure 

and sensitivity are inseparable from large-scale processes of sociocultural change and 

market integration.” In this way, issues of scale complicate vulnerability assessments as 

the processes driving change are often spatially or temporally removed from the site of 

concern (see Box 2). Leichenko and O’Brien (2002, 2008) and O’Brien and Leichenko 

(2003), for instance, demonstrate that multiple stressors, originating from complex and 

trans-local networks, can interact to create “double exposures,” deepening vulnerability. 

In their work, they demonstrate how climate change stressors (i.e., increasing drought 

with a shorter but more dramatic monsoon season) and global economic shifts (i.e., 

decreasing crop prices) combined to impact the vulnerability of a rural Indian farming 

community. In many ways, these observations are equally true regarding adaptive capacity. A beetle outbreak, combined with the closure of a mill due to increases in Canadian 

lumber imports and the price of wood products, could affect a forest community’s ability 

to respond to change.

Summary

We outlined some of the different ways that vulnerability is conceptualized, from 

systems- to actor-oriented, and outcome- to context-oriented perspectives. Critical 

differences concern the factors that may influence vulnerability and how these factors 

are understood and examined. These differences can be thought of as falling around 

different conceptual scales: the difference between systems and actor approaches is the 

focus on the individual agent (actor-oriented) versus the broader context of vulnerability (systems-oriented), whereas outcome and contextual approaches are distinguished 
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-328. 2015 13

by the scope of factors considered to shape or produce vulnerability. Outcome-based 

approaches tend to adopt a more narrow focus, largely mirroring the IPCC definition 

of vulnerability, while contextual approaches adopt a more holistic picture of how the 

socio-political and historical context shapes vulnerability. This conceptual complexity 

makes it difficult to sort out the influence of these different perspectives on how we 

understand and assess vulnerability and adaptive capacity. Still, the important insight 

to take away from this discussion is that different ways of thinking about and conceptualizing vulnerability highlight and prioritize different aspects of vulnerability and 

adaptive capacity. Emerging from the complexity, the next step is to understand how 

these ideas are applied in practice.

Box 2: Ethics and Vulnerability Assessments

Assessments of vulnerability raise important ethical questions concerning the conduct 

and implications of research. Understanding how communities are differentially affected by 

climate change is a principal driver of vulnerability assessments. These assessments raise 

questions about ethics and equity, as vulnerability is a product of access to resources, risk 

exposure, and the socio-political context that has created these conditions now and into 

the future (Eakins and Luers 2006; Ribot 2011). Once complete, vulnerability assessments 

stimulate broader questions for policy and practice. Why is a particular group vulnerable or 

at risk, and what are the possible steps that can be taken to address the condition of vulnerability? Is the research complete once the vulnerable populations are identified, or is there 

a responsibility to act on this knowledge? In some agency contexts, the policies or politics 

may prevent researchers from directly acting on vulnerability assessments. This does not, 

however, negate consideration of the ethical implications of the research. 

The very act of labeling a social group, community, or region as vulnerable should be 

viewed with caution. Such a label has the potential to construe these groups or individuals 

as passive victims, ignoring their potential agency (the ability of individuals or groups to 

make change). Agency is apparent in contextual research, which focuses on the broader 

socio-political forces shaping vulnerability. Seeing vulnerability only as a state of “powerlessness” (Hewitt 1997) can result from outcomes-oriented indicator research because there 

is little attention devoted to why a particular group is vulnerable and who is responsible 

for creating or addressing drivers of vulnerability. Acknowledging the creative and powerful actions of the vulnerable is particularly important if we want forest communities to be 

active participants in developing adaptation actions in the face of climate change. Further, 

when vulnerability assessments are used as a platform for allocating resources or designing 

policy, wrongly labeling a group as vulnerable not only denies their agency in addressing 

solutions, but finite resources could be allocated to areas with less need at the cost of those 

with greater needs for assistance. 

Importantly, what constitutes damage, negative effects, or adaptation varies across 

contexts and cultures. Vulnerability research is unavoidably grounded in human values 

attached to particular places, populations, and systems (Farely and Costanza 2002; Eakin 

and Luers 2006; O’Brien and others 2007). Support for adaptation and mitigation to address vulnerability contain (often hidden) value judgments about the relative importance of 

certain communities or social groups. Even rigorous scientific research using metrics and 

indicators involves simplification and aggregation of complex processes to enable analysis. 

Reconfiguring these metrics can produce vastly different results with significant implications 

for understanding who is vulnerable and what can or should be done (Nelson and others 

2010; see Case Example Two).
14 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-328. 2015

Assessments and Methodologies ___________________

Not surprisingly, social vulnerability is measured in a number of different ways, as 

different conceptual frameworks imply different data needs (Costa and Kropp 2013) (see 

Table 2). For example, contextual approaches are more likely to search for the broader 

social, political, and economic forces driving vulnerability and are more likely to adopt 

methods that illuminate these factors at a local scale. In contrast, outcome-oriented research is more likely to focus on indicators of vulnerability that measure and monitor the 

potential impacts of an event or disturbance on a population or sector of the community.

Table 2—Methods for research and assessment.

Research design

and/or 

methodology Elements Pros Cons

Dose-Response Vulnerability is assessed Targeted, simple, and Only applicable to past events,

(Outcome- through quantitatively cost efficient. highly reductionist, and

oriented) measured impacts. utilizes only quantitative data.

Indices and Past event data are used Good for targeting. High Founded on core assumptions

Indicators to create index, weighted external validity (presumed). that may be misleading.

(Outcome- through expert elicitation, Scalable and cost effective. Reductionist. Serious

oriented) and then used to assess Data are easily accessible. measurement issues. Typically

relative vulnerability or Can be represented only uses quantitative data.

adaptive capacity. spatially on a map.

Case Studies Empirically trace out drivers Highly detailed, complex, Time intensive, overly specific,

(actor- and and processes from “field.” and realistic understandings. complex, and costs can be

context-oriented) Empirically rich. high. Not always scalable.

Scenario-building Climate models used to Useful in quantitative and Highly specific and localized.

(Combination of assess future impacts or to qualitative research designs. Methods can be scaled up, but

outcome and plan for future adaptation. Can be used in participatory not necessarily findings.

context-oriented) Successive “what if” work. Helps decision-makers

scenarios are presented. and community members work

through problems.

Participatory Assessment through locally Locally meaningful, cost- Overly specific, may be clouded

(actor- and context- meaningful research. effective, and considers by local perceptions, not

oriented, could widest range of perspectives. scalable, and may experience

be systems- and resistance.

outcome-oriented)

Eakin and Luers (2006) identified twelve components of a vulnerability assessment 

along with associated questions (see Table 3). These questions (and their answers) can 

inform decisions about the scope of the study and the research questions. Questions such 

as What is the scope of the assessment? and Why do we care? help focus a vulnerability 

assessment. Questions such as What social and biophysical factors are driving change 

in the system? and Who loses, who gains? can be seen as possible research questions. 

When the assessment is connected to adaptation policy and planning, understanding 

why certain communities are vulnerable helps to develop appropriate management actions and responses.
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-328. 2015 15

Table 3—Core components of vulnerability assessment (Eakin and Luers 2006).

Assessment component Questions

Definition of the system What is the scope of the assessment?

Definition of the desired state(s) Why do we care? 

of the system What future is valued highly in this system? 

Whose values are important, and why?

Definition of the exposure units Who or what is potentially vulnerable?

Identification of attributes of What is dangerous or undesirable for the

concern and definition of damage unit(s) of analysis? 

What is dangerous for the system of study?

What is the relationship between harm and

the unit of study and harm and the human 

environment system?

Identification of proximate and What social and biophysical factors are

underlying drivers of the system driving change in the system?

Delineation of interactions What are the immediate threats, and how

among drivers are they evolving?

Delineation of interactions What are the greatest uncertainties about

between drivers and unit(s) the system’s change? 

of analysis What are the underlying causes of

differential susceptibility?

Evaluation of differential Who or what has the least capacity to

capacities and sensitivities respond, and why? 

What explains differential capacities to

cope and adapt? 

Why and how do systems change?

Identification of thresholds How can a shift in the state of the system

of change be observed? 

What indicators will signal that a threshold 

has been passed? 

How does the identified threshold relate to 

the desired state of the system or welfare 

of the unit(s) of exposure?

Model relationship between How does the system respond to stress?

stressors, attributes, and 

outcomes

Characterization and evaluation of What range of changes can be expected? 

plausible outcomes of change What outcomes are least tolerable? 

Who loses, and who gains?

Characterization of adaptation What actions can be taken now to 

actions increase future flexibility? 

What capacities are needed to enable 

desired response to change? 

What policies are needed to support these 

capacities?
16 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-328. 2015

Because no two communities, landscapes, or local economies are the same, vulnerability assessments are likely to be most effective when tailored to a specific context, 

such as climate change on a particular national forest. Hinkel (2011) identified the following motivations for assessing vulnerability:

1. Identify mitigation targets

2. Identify particularly vulnerable people, regions, or sectors

3. Raise awareness of climate change

4. Allocate adaptation funds to particular vulnerable regions, sectors, or groups of 

people

5. Monitor the performance of adaptation policy

6. Conduct scientific research

This diversity of motivations combined with the diversity of definitions previously 

discussed and the diversity of communities for which a social vulnerability assessment 

might be conducted mean that methods are unlikely to boil down to a single recipe 

(Eakins and Luers 2006). For example, a participatory approach engaging different actors in developing a community-scale vulnerability assessment is more likely to raise 

awareness about climate change (at that local scale) than an expert-led process to develop 

indicators and metrics of vulnerability. These indicators and metrics are, however, useful to identify vulnerable populations, regions, or sectors, highlighting where policy or 

future research should target adaptive strategies or efforts.

The following discussion outlines the primary methods used in vulnerability research 

and assessment. Here, we highlight the strengths and weaknesses of these approaches 

and have included three case studies to illustrate how these approaches have been applied in practice.

Dose-Response

The primary methodology of large-scale, outcome-oriented, climate change vulnerability analyses involves some kind of dose-response model of experimentation (O’Brien 

and others 2007). In a dose-response approach, vulnerabilities are measured through 

the impact a particular hazard inflicts on a given population or economic sector. The 

dose is the magnitude of the hazard—the size of a flood or duration of a drought, for 

example. Dose-response research focuses on understanding which regions, communities, 

or economic sectors are exposed to a particular climate-related hazard and the extent to 

which they are exposed. For example, this work might explore the impact of wildfire 

distribution and frequency on home values. Geographic Information System (GIS) 

analyses can be utilized to examine the spatial impact of different “doses” or amounts 

of a hazard experienced. This produces spatial information indicating who is exposed 

to a particular hazard. Dose-response research can reveal which groups or communities are more likely to be exposed to a particular hazard, such as sea level rise, fire, or 

drought, but it does not measure sensitivity to those hazards and is thus an imperfect 

measure of social vulnerability.
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-328. 2015 17

Indices and Indicators

Much of the research on climate change vulnerability has utilized some kind of 

indicator methodology. As previously discussed, indicators are most often associated 

with an outcome-oriented approach and are typically based on an assumption that 

vulnerability is something inherent in certain social groups (e.g., the poor). In this 

vein, the determinants and drivers of vulnerability and adaptation, such as income and 

education level, are derived from broader literature and case studies of hazard impacts 

and outcomes (Ligon and Schechter 2003; Brooks and others 2005; Birkmann 2006; 

Jones and Andrey 2007; Johnson and others 2009). Researchers rely on expert elicitation to weigh particular indicators, such as income, gender, or education, and then use 

the established index to rank or rate households, communities, or larger units, such as 

countries, according to their relative vulnerability or adaptive capacity. This research 

is scalable and cost-effective because it relies solely on existing data sources, such as 

census data. It has also been highly valued as a targeting tool. For example, an index 

derived from expert elicitation and existing data on hazards could enable communities 

to be assessed, ranked, and targeted for vulnerability reduction and adaptive capacity building. Indicator data can also be represented spatially on a map, which enables 

decision-makers to consider vulnerability “hot spots” as they consider different approaches to climate change adaptation.

While indicator studies are quite popular, there are a number of concerns about their 

utility. For instance, these studies may not necessarily measure what they intend to measure, as they can oversimplify complex relationships between variables and the associated 

metrics are often determined by data availability rather than the underlying validity of 

the available parameters. Additionally, participating experts may not have a complete 

understanding of the phenomena and indicators that predict vulnerability in one context 

may not translate to other contexts as hypothesized relationships between variables may 

not exist in the real world. For example, the assumption that vulnerability is positively 

correlated with poverty might be an ineffective measure of wildfire vulnerability in forest communities with a large number of wealthy amenity homeowners. Some indicator 

research considers only economic losses or mortality and neglects other kinds of loss 

such as community character or cultural values that may also be meaningful to local 

groups (see Crate and Nuttall 2009). Indicator work is also often excessively focused 

on constraints and characteristics that are lacking rather than factors that contribute to 

the ability of groups to take action and respond constructively.

Despite these short-comings, there are good reasons to continue indicator studies at 

some levels. Nelson and others (2010) distinguished between general vulnerability and 

specific vulnerability, pointing out that indicator research is helpful in understanding 

vulnerability more generally. The fundamental purpose of such work is to highlight 

deficiencies in adaptive capacity so that initiatives can be appropriately targeted to support capacity building where necessary. Adger (2006) argued that targeting resources 

to specific groups or regions should be the primary purpose of indicator studies, while 

Hinkel (2011) suggested that indicators are only useful for identifying vulnerable entities when systems can be narrowly defined by a few variables or as starting points to 

future, more detailed inquiry.
18 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-328. 2015

Case Example One: The vulnerability of Australian rural communities to climate 

variability and change (Nelson and others 2010)

This study combined traditional hazards impact mapping and modeling with a composite 

indicator of adaptive capacity to develop a nuanced picture of regional social vulnerability 

in Australia. The research aimed to move beyond simple metrics of vulnerability to generate 

information that could be used to identify and enhance transformative measures of adaptive 

capacity. In a three-tiered approach, historical, social, and biophysical data were combined 

to develop an integrated vulnerability metric. Exposure was measured through a coefficient 

of variation for three factors: historic rainfall, simulated pasture growth, and historical farm 

income data over a 10-year period (1996/1997 to 2005/2006.) These factors were modeled 

out to 2030 to project impact of climatic changes in rainfall, pasture, and income. The second 

step involved developing an adaptive capacity index, which was constructed using the rural 

livelihoods analysis. This analysis framed adaptive capacity as an emergent property of diverse 

forms of human, social, natural, physical, and financial capital central to rural livelihoods and 

the flexibility to substitute among capitals in response to stressors. The results of both stages 

were then spatially presented using GIS to determine the integrated vulnerability measure 

determined as areas with high or moderate exposure and low to moderate adaptive capacity.

The integrated metric of vulnerability showed a vastly different spatial distribution of 

vulnerability as compared with vulnerability viewed simply as an impact of hazards. The 

integrated metric revealed that areas with high climatic variability were not necessarily those 

with highly variable farm incomes. This finding demonstrates capacities of different people 

and groups to manage for variability but also highlights the challenges associated with using 

simple indices of vulnerability. The way the metric is defined and calculated influences the 

results; this can have important implications for policy and program delivery if the metric 

is calibrated incorrectly or neglects critical contextual factors shaping vulnerability. 

Case Studies

Case study approaches attempt to uncover underlying drivers and processes leading 

to vulnerability or generating adaptive capacity, typically at the community or household 

level of analysis. Included in this context-oriented research design is a mix of data collection methodologies with a strong reliance on qualitative methods such as interviews, 

focus groups, participant observation, and archival analysis (see Adger and Kelly 1999; 

Adger and others 2002; Eriksen and others 2005). In case study research, the dynamics and causal factors generating vulnerability are traced out in ways that more closely 

reflect the actualities of real, on-the-ground processes. As Smit and Wandel (2006:285) 

stated, the central goal of this approach is “to document the ways in which the system 

or community experiences changing conditions and the processes of decision-making in 

this system (or that influence the system) that may accommodate adaptations or provide 

means of improving adaptive capacity.” The case study approach fits with a contextual 

approach, whether through an actor-orientation or systems-orientation.

Case study research builds an understanding of the dynamics and causal factors shaping vulnerability that matches the complexity found in actual communities. Case study 

research can also effectively trace out the ways that local places are connected to larger 

scales; though, it is less capable of describing larger-scale dynamics in detail. Obtaining these rich insights requires significant time and effort to conduct in-depth qualitative research. Further, case study research cannot typically be generalized to broader 

populations and thus is not intended to be “scaled-up” to larger regions. Cutter (2003) 

critiqued case studies for being overly specific and suggested that findings may not be 

applicable to other contexts. That said, a case study approach can provide important 

information for developing locally targeted adaptive strategies or programs used at the 

site of the research (i.e., for particular communities or national forests).
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-328. 2015 19

Scenario Processes

Scenarios have become a popular communication tool in climate change research 

(McCarthy and others 2001). Scenarios use storylines developed from current patterns 

of economic, social, ecological, and cultural change to convey different plausible futures 

(Raskin 2005; Tompkins and others 2008; Wilkinson and Eidinow 2008; Gidley and 

others 2009; Hallegatte and others 2011; Ozkaynak and Rodriguez-Labajos 2010). By 

describing a range of plausible futures, scenarios can inform decisions about climate 

change adaptation in the context of uncertainty regarding exactly how local landscapes 

will change in response to warming trends (Parson 2008). Scenarios can be either a 

product (where the scenarios themselves are the research output) or a process (where 

the goal is to generate new knowledge and insight through the scenario process, which 

is used to stimulate discussion and reflection on different possible futures) (Wilkinson 

and Eidinow 2008). When employed in social vulnerability assessment, scenarios serve 

as a tool to understand how vulnerability differs across different plausible futures, how 

human communities respond and deal with uncertainties, and what kids of capacities are 

required to respond under different scenarios. Thus, the scenarios are not the product of 

the research in and of themselves; they are simply a tool to help understand vulnerability.

Process-based scenarios are gaining in popularity as they focus on developing practical 

knowledge to aid decision-making through dialogue about plausible futures (Figure 5). 

These process-based scenarios (scenarios used in a decision-making or research process) are local in scale (O’Neil and others 2008) and use climate change projections 

to describe how local landscapes might change in response to warming trends. Studies 

typically utilize three to four qualitative storylines in accessible lay language to depict 

the range of possible changes.

Product-based scenarios can, like the indicator research previously described, be used 

in large-scale assessments to target and prioritize vulnerability reduction and adaptation 

efforts. While product-based scenarios are useful at the national to global scale, processbased scenarios work best at the community and household scale. The challenge at a 

more local scale is the considerable amount of work required to generate scenarios that 

contain enough detail to be useful for understanding social vulnerability at the level of 

communities and households.

Figure 5—Two researchers engage a group of local stakeholders 

in a scenario building process for southwest Colorado. Photograph 

by the Mountain Studies Institute.
20 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-328. 2015

Case Example Two: Vulnerability of water supply from the 

Oregon Cascades to a changing climate (Farley and others 2011)

This study sought to understand how changes in the timing and quantity of streamflow 

into the McKenzie River Basin would shape vulnerability of water users. In particular, the 

authors were interested in whether existing management institutions were able to take spatial and temporal aspects of stream flow into account when responding to predicted climate 

changes. This study applied a “scenario as process” approach, combining historical data 

and modeled predictions of changes in stream flows to develop a scenario of future change 

that was presented to 18 interviewees from 4 key water sectors: fish habitat (U.S. Fish and 

Wildlife Service); flood control (U.S. Army Corps of Engineers); municipal water authority 

(Eugene Water and Electric Board); and recreational fishing (a guided fishing operation). 

Once the scenarios were developed, participants were asked to discuss the implications of 

these conditions for their area of concern, how they would respond to these conditions, the 

institutions in place to help respond to climate change, and the availability and access to 

relevant information related to climate change impacts on stream flows. 

This study revealed high variability in the implications of changing stream flows across 

sectors. For example, municipal water users have a heightened sensitivity to projected alterations to streamflow as the projected decrease in timing of peak flows coincides with the peak 

demand, whereas for fishing guides, impacts of decreased summer flows may be offset by 

changes in spring flow. These vulnerabilities were mediated by both the spatial and temporal 

dimensions of stream flow and the varied institutional context of the actors. The authors 

were also able to see how decisions made by one sector would have implications for actors 

in other areas. Specifically, while U.S. Army Corps of Engineers has the physical capacity 

to offset some of the implications of decreased summer flows for other uses, its mandate 

to manage for flood control restricts its capacity to maintain summer flows for other uses. 

As the mandates are dictated by Congress, changes to these requirements are difficult. This 

shows how institutional constraints or decisions made by those who manage stream flows 

shape the vulnerability of those sectors that are highly sensitive to temporal variation in 

flows. By asking actors how they would respond and what would constrain their adaptation 

actions, the authors were also able to identify how the different institutional contexts across 

sectors either impede or enable adaptation. 

Participatory Approaches

Through stakeholder consultation and public engagement processes, participatory 

approaches seek local definitions of the hazards, risks, and uncertainties that pose threats 

and how they might manifest in locally meaningful ways (see Tompkins and others 2008). 

A participatory approach in a community might involve local stakeholders in developing 

a list of local vulnerabilities and context-appropriate means to measure these vulnerabilities. Participatory assessments often utilize both case study research and indicator 

assessments. Because local stakeholder involvement builds a rich understanding of local 

context, participatory approaches allow for the recognition of multiple, complex, and 

overlapping sources and determinants of vulnerability and adaptive capacity. Moreover, 

this kind of assessment creates the kind of “buy-in” that is necessary to move research 

results into management actions and policy change to reduce vulnerability and build 

adaptive capacity.

However, like case study approaches, results are highly contextualized and case specific and thus may not be more broadly generalizable. This poses a problem for scaling 

up and applying findings to other contexts.
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-328. 2015 21

Case Example Three: Assessing social vulnerability: a study of 

the mountain pine bark beetle outbreak in British Columbia, Canada 

(Parkins and MacKendrick 2007)

Using a participatory and multi-disciplinary approach, Parkins and MacKendrick (2007) 

conducted a social vulnerability assessment in response to a major outbreak of mountain 

pine beetle (MPB). The study was grounded in climate science and forest sociology and 

used focus groups to incorporate community perspectives into the research from an early 

stage. Of particular note, this study developed a framework to combine bio-physical risk 

factors (exposure) with community assessments of risk. Understanding how a community 

perceives risk can provide critical insights into its capacity and willingness to act: those with 

a high perception of risk are more likely to adopt voluntary adaptations and more willing to 

accept policies and programs targeted at minimizing risk.

At the outset, the researchers asked focus group participants to discuss:

1. Current and future social and economic impacts from MPB

2. Factors contributing to the community’s adaptive capacity

3. Past hardships in the community that could influence present or future adaptive 

capacity

4. Community awareness of MPB

5. Organisational responsibility for dealing with social and economic impacts from 

MPB

Participants were selected to represent a range of economic, public agencies, forestry, 

health, social services, and other organizations. The findings of the focus groups were then 

used to develop a vulnerability framework containing four dimensions: physical, social, 

political, and economic. The second phase of the research gathered data from household 

surveys to measure the indicators of vulnerability and determined aggregate vulnerability 

scores under each dimension. Beyond the focus groups, the framework was configured to 

match available data, thus allowing flexibility within the metric. 

The holistic approach adopted in this study created a framework to capture multi-dimensional 

nature of risks and vulnerabilities. Breaking down measures of vulnerability into political, 

economic, and physical exposure creates a more nuanced picture of what aspect of the system 

or community is vulnerable and, through doing so, identifies avenues for targeted interventions tailored to the context. For example, in the town of 100 Mile House, it was deduced 

that high levels of physical risk in some communities were tempered by other factors such 

as availability of alternative resources and high levels of trust in political actors. In combination, these factors increased the community’s capacity to manage impacts and outcomes of 

MPB. These types of community-level assessments can provide a contextual understanding 

of exposure and response capacity that are obscured in regional- or national-scale analysis. 

Moreover, these studies are well suited to identify areas of strengths and weaknesses to target 

action. According to Parkins and MacKendrick, this then enables vulnerability assessments 

to become a tool to support action and build adaptive capacity.

Conclusion ______________________________________

Social vulnerability assessments not only fulfill the requirements of the Forest Service 

Climate Change Performance Scorecard, they also help national forests understand the 

ways in which climate change impacts on national forest lands affect nearby communities and their relationships with forest resources. Rather than thinking about single 

and immediate hazards and impacts (e.g., smoke from a wildfire happening right now), 

vulnerability assessments enable forests to consider multiple biophysical stressors (e.g., 

drought and fire) over longer time scales (e.g., 10 to 30 years) that affect different 

groups of people differently (e.g., unemployed mill workers versus wealthy retirees) 
22 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-328. 2015

and how these stressors interact with other social processes (e.g., economic downturns 

or changes in water rights). Vulnerability research also illuminates the different capacities that individuals and communities have to adapt and how those capacities might be 

strengthened. Vulnerability research helps understand the “multiple and interacting social 

and environmental stressors” that create climate change impacts (McLaughlin and Dietz 

2008:99). Improved knowledge of social vulnerability will help national forests engage 

local communities in climate change adaptation planning that benefits both ecosystems 

and human communities.

While this report is not intended to serve as a how-to guide to conducting vulnerability assessments, it should provide a sense of the conceptual and methodological 

landscape that informs such assessments and the ways in which different definitions of 

vulnerability lead to different methodological choices (each with their own strengths 

and weaknesses). Conceptual frameworks matter because they drive the way in which 

vulnerability, adaptive capacity, and adaptation are understood, which has implications 

for the conduct of research, its outputs, and the policy and management recommendations. This document should help researchers, policy-makers, and practitioners new to 

the field of vulnerability and adaptive capacity to understand the diversity of different 

methods and how they are connected to different conceptual framings. In deciding how 

to move forward, national forests and other public land management agencies will need 

to consider their data needs, budget and capacity, and adaptation plans. Research that 

draws on existing data as indicators of social vulnerability might serve as an initial study 

in the context of budget restrictions. However, where national forests want to integrate 

local community needs into adaptation planning, more detailed assessments utilizing 

case study or participatory methods might be necessary.

References ______________________________________

Adger, W.N. 2006. Vulnerability. Global Environmental Change 16:268-281.

Adger, W.N. and K. Vincent. 2005. Uncertainty in adaptive capacity. Geoscience 337:399-410.

Adger, W.N. and P.M. Kelly. 1999. Social vulnerability to climate change and the architecture of entitlements. Mitigation and Adaptation Strategies for Global Change 4:253-266.

Adger, W.N., Kelly, P.M., Winkels, A., Huy, L.Q. and C. Locke. 2002. Migration, remittances, livelihood 

trajectories and social resilience. Ambio 31:358-366.

Adger, W.N., Dessai, S., Goulden, M., Hulme, M., Lorenzoni, I., Nelson, D.R., Naess, L.O., Wolf, J. and 

A. Wreford. 2009. Are there social limits to adaptation to climate change? Climatic Change 93:335-354.

Berkes, F. 2007. Understanding uncertainty and reducing vulnerability: Lessons from resilience thinking. 

Natural Hazards 41:283-295.

Berkhout, F., Hertin, J. and D.M. Gann. 2006. Learning to adapt: Organizational adaptation to climate 

change impacts. Climatic Change 78:135-156.

Birkmann, J. 2006. Indicators and criteria for measuring vulnerability: Theoretical bases and requirements. 

In: Measuring Vulnerability to Natural Hazards. New York, United Nations Press.

Brooks, N., Adger, W.N. and P.M. Kelly. 2005. The determinants of vulnerability and adaptive capacity 

at the national level and the implications for adaptation. Global Environmental Change 15(2):151-163.

Costa, L. and J.P. Kropp. 2013. Linking components of vulnerability in theoretic frameworks and case 

studies. Sustainability Science 8(1):1-9.

Crate, S. and M. Nuttall. 2009. Anthropology and Climate Change: From Encounters to Actions. Walnut 

Creek, CA, Left Coast Press.

Cutter, S. 2003. The vulnerability of science and the science of vulnerability. Annual Association of American Geographers 93(1):1-12.

Davidson, D. 2010. The applicability of the concept of resilience to social systems: Some sources of optimism and nagging doubts. Society and Natural Resources 23(12):1135-1149.

Eakin, H. and A. Luers. 2006. Assessing the vulnerability of social-environmental systems. Annual Review 

of Environment and Resources 31:365-394.

Eakin, H. and M.C. Lemos. 2006. Adaptation and the state: Latin America and the challenge of capacitybuilding under globalization. Global Environmental Change 16:7-18.

Eriksen, S., Brown, K. and P.M. Kelly. 2005. The dynamics of vulnerability: Locating coping strategies in 

Kenya and Tanzania. Geographical Journal 171:287-305.
USDA Forest Service Gen. Tech. Rep. RMRS-GTR-328. 2015 23

Farely, J. and R. Costanza. 2002. Envisioning shared goals for humanity: A detailed, shared vision of a 

sustainable and desirable USA in 2010. Ecological Economics 43(2-3):245-259.

Farley, K., Tague, C. and G.E. Grant. 2011. Vulnerability of water supply from the Oregon Cascades to 

changing climate: Linking science to users and policy. Global Environmental Change 21:110-122.

Fischer, A.P., Paveglio, T., Carroll, M., Murphy, D. and H. Brenkert-Smith. 2013. Assessing social vulner-

ability to climate change in communities near public forests and grasslands: A framework for resource 

managers and planners. Journal of Forestry 111(5):352-369.

Gibson, C.C., Ostrom, E. and T.K. Ahn. 2000. The concept of scale and the human dimensions of global 

change: A survey. Ecological Economics 32(2):217-239.

Gidley, J., Fien, J., Smith, J-A., Thomsen, D. and T. Smith. 2009. Participatory future methods: Towards 

adaptability and resilience in climate-vulnerable communities. Environmental Policy and Governance

19:427-440.

Grothmann, T. and A. Patt. 2005. Adaptive capacity and human cognition: The process of individual ad-

aptation to climate change. Global Environmental Change 15:199-213.

Gunderson, L. and C.S. Holling. 2002. Resilience and adaptive cycles. In: Panarchy: Understanding 

Transformations in Human and Natural Systems. Washington, DC, Island Press.

Hallegatte, S. 2009. Strategies to adapt to an uncertain climate change. Global Environmental Change

19(2):240-247.

Hallegatte, S., and others. 2011. Building world narratives for climate change impact, adaptation and 

vulnerability analyses. Nature Climate Change 1:151-155.

Hewitt, K. 1997. Regions of Risk: A Geographical Introduction to Disasters. Essex, U.K., Longman.

Hinkel, J. 2011.Indicators of vulnerability and adaptive capacity: Towards a clarification of the sciencepolicy interface. Global Environmental Change 21:198-208.

Hulme, M. 2009. Why We Disagree About Climate Change: Understanding Controversy, Inaction, and 

Opportunity. Cambridge, MA, Cambridge University Press.

Ingold, K., Balsiger, J. and C. Hirschi. 2010. Climate change in mountain regions: How local communities 

adapt to extreme events. Local Environment 15(7):651-661.

IPCC. 2013. Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the 

Fifth Assessment Report of the Intergovernmental Panel on Climate Change. Stocker, T.F., and others 

(eds.). Cambridge University Press: Cambridge, United Kingdom and New York.

Johnson, D.P., Wilson, J.S. and G.C. Luber. 2009. Socioeconomic indicators of heat-related health-risk 

supplemented with remotely sensed data. International Journal of Health Geographics 8:57-70.

Jones, B. and J. Andrey. 2007. Vulnerability index construction: Methodological choices and their influences 

on identifying vulnerable neighborhoods. International Journal of Emergency Management 4(2):269-295.

Krasny, M.E., Lundholm, C. and R. Plummer. 2011. Resilience in Social-Ecological Systems: The Role of 

Learning and Education. New York, Routledge.

Leichenko, R. and K. O’Brien. 2002. The dynamics of rural vulnerability to global change: The case of 

Southern Africa. Mitigation and Adaptation Strategies for Global Change 7:1-18.

Leichenko, R. and K. O’Brien. 2008. Environmental Change and Globalization: Double Exposures. Oxford, 

Oxford University Press.

Lemos, M.C., Agrawal, A., Eakin, H., Nelson, D.R., Engle, N.L. and O. Johns. 2013. Building adaptive 

capacity to climate change in less developed countries. In: Asrar, G.R. and J.W. Hurrell, Eds. Climate 

Science for Serving Society: Research, Modeling, and Prediction Priorities. Dordrecht, The Netherlands, 

Springer.

Ligon, E. and L. Schechter. 2003. Measuring vulnerability. Economic Journal 113:C95-C102.

Lynn, K., MacKendrick, K. and E. Donoghue. 2011. Social vulnerability and climate change: Synthesis 

of literature. Gen. Tech. Rep. PNW-GTR-838. Portland, OR: U.S. Department of Agriculture, Forest 

Service, Pacific Northwest Research Station. 70 p.

McCarthy, J., Canziani, O.F., Leary, N.A., Dokken, D.J. and K.S. White, Eds. 2001. Climate change 2001: 

Impacts, adaptation, vulnerability. Contribution of Working Group II to the Third Assessment Report of 

the Intergovernmental Panel on Climate Change. Cambridge, Cambridge University Press.

McLaughlin, P. and T. Dietz. 2008. Structure, agency and environment: Toward an integrated perspective 

on vulnerability. Global Environmental Change 18:99-111.

Nelson, D., Adger, W.N. and K. Brown. 2007. Adaptation to environmental change: Contributions of a 

resilience framework. Annual Review Environment and Resources 32:395-419.

Nelson, R., Kokic, P., Crimp, S., Martin, P., Meinke, H., Howden, S.M., deVoil, P., McKeon, G. and U. 

Nidumolu. 2010. The vulnerability of Australian rural communities to climate variability and change. 

Environmental Science and Policy 13(1):18-27.

Norgaard, K.M. 2011. Living in Denial: Climate Change, Emotions, and Everyday Life. Cambridge, MA, 

MIT Press.

O’Brien, K. and G. Hochachka. 2010. Integral adaptation to climate change. Integral Theory and Practice

5(1):89-102.
24 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-328. 2015

O’Brien, K.L. and R.M. Leichenko. 2003. Winners and losers in the context of global change. Annals of 

the Association of American Geographers 93:89-103.

O’Brien, K., Eriksen, S., Lynn, P.N. and A. Schjolden. 2007. Why different interpretations of vulnerability 

matter in climate change discourses. Climate Policy 7(1):73-88.

O’Neil, B., Pulver, S., VanDeveer, S. and Y. Garb. 2008. Where next with global environmental scenarios. 

Environmental Research Letters 3:1-4.

Ozkaynak, B. and B. Rodriguez-Labajos. 2010. Multi-scale interaction in local scenario-building: A methodological framework. Futures 42:995-1006.

Pahl-Wostl, C. 2009. A conceptual framework for analyzing adaptive capacity and multi-level learning 

processes in resource governance regimes. Global Environmental Change 19(3):354-365.

Parkins, J. and N. MacKendrick. 2007. Assessing community vulnerability: A study of the mountain beetle 

outbreak in British Columbia, Canada. Global Environmental Change 17(3-4): 460-471.

Parson, E.A. 2008. Useful global-change scenarios: Current issues and challenges. Environmental Research 

Letters 3:1-5.

Pelling, M. 2010. Adaptation to Climate Change: From Resilience to Transformation. New York, Routledge.

Pelling, M., High, C., Dearing, J., and D. Smith. 2008. Shadow spaces for social learning: A relational 

understanding of adaptive capacity to climate change within organizations. Environment and Planning 

A 40(4):867-884.

Raskin, P.D. 2005. Global scenarios: Background review for the millennium ecosystem assessment. Ecosystems 8:133-142.

Ribot, J. 2011. Vulnerability before adaptation: Toward transformative climate action. Global Environmental 

Change 21(4):1160-1162.

Roberts, J.T. and B. Parks. 2006. A Climate of Injustice: Global Inequality, North-South Politics, and 

Climate Policy. Cambridge, MA, MIT Press.

Rodima-Taylor, D. 2012. Social innovation and climate adaptation: Local collective action in diversifying 

Tanzania. Applied Geography 33:128-134.

Shackley, S. and R. Deanwood. 2002. Stakeholder perceptions of climate change impacts at the regional 

scale: Implications for the effectiveness of regional and local responses. Environmental Planning and 

Management 45(3):381-402.

Smit, B. and J. Wandel. 2006. Adaptation, adaptive capacity and vulnerability. Global Environmental 

Change 16:282-292.

Smit, B., Burton, I., Klein, R.J.T. and J. Wandel. 2000. An anatomy of adaptation to climate change and 

variability. Climatic Change 45:223-251.

Thornton, T.F. and N. Manasfi. 2010. Adaptation–genuine and spurious: Demystifying adaptation processes 

in relation to climate change. Environment and Society 1:132-155.

Tompkins, E.L., Few, R., and K. Brown. 2008. Scenario-based stakeholder engagement: Incorporating 

stakeholders preferences into coastal planning for climate change. Journal of Environmental Management 88:1580-1592.

Tschakert, P. and K.A. Dietrich. 2010. Anticipatory learning for climate change adaptation and resilience. 

Ecology and Society 15(2):11.

Tucker, C., Eakin, H., and E.D. Castellanos. 2010. Perceptions of risk and adaptation: Coffee producers, 

market shocks, and extreme weather in Central America and Mexico. Global Environmental Change

20:23-32.

Vincent, K. 2007. Uncertainty in adaptive capacity and the importance of scale. Global Environmental 

Change 17:2-24.

Wall, E. and K. Marzall. 2006. Adaptive capacity for climate change in Canadian rural communities. Local 

Environment 11(4):373-397.

Wilbanks, T. and R.W. Kates. 1999. Global change in local places: How scale matters. Climatic Change

43:601-628.

Wilkinson, A. and E. Eidinow. 2008. Evolving practices in environmental scenarios: A new scenario typology. Environmental Research Letters 3(4):1-11.

Wisner, B., Blaikie, P., Cannon, T. and I. Davis. 2004. At Risk: Natural Hazards, People’s Vulnerability, 

and Disasters. New York, Routledge.

Yohe, G. and R.S.J. Tol. 2002. Indicators for social and economic coping capacity: Moving toward a working definition of adaptive capacity. Global Environmental Change 12:25-40.

Young, K.R. and J.K. Lipton. 2006. Adaptive governance and climate change in the tropical highlands of 

Western South America. Climatic Change 78:63-102.

Zahran, S., Brody, S.D., Vedlitz, A., Grover, H. and C. Miller. 2008. Vulnerability and capacity: Explaining local commitment to climate-change policy. Environment and Planning C: Government and Policy

26(3):544-562.

To learn more about RMRS publications or search our online titles:

www.fs.fed.us/rm/publications

www.treesearch.fs.fed.us

Federal Recycling Program Printed on Recycled Paper

USDA is an equal opportunity provider and employer. To file a complaint of discrimination, write: USDA, Office of the Assistant Secretary for Civil Rights, Office 

of Adjudication, 1400 Independence Ave., SW, Washington, DC 20250-9410 or 

call (866) 632-9992 (Toll-free Customer Service), (800) 877-8339 (Local or Federal 

relay), (866) 377-8642 (Relay voice users).