Climate Change: Defining Adaptation and Resilience, with Implications for Policy

Climate Change: Defining Adaptation and Resilience, with Implications for Policy

May 11, 2021
Climate Change: Defining Adaptation and Resilience, with
Implications for Policy
Congress has increased its attention to risks that climate
Definitions of Climate Change Adaptation
variability and change pose to communities, the economy,
Scientific and programmatic literature defines adaptation in
and other dimensions of society. Legislative provisions
various ways. Below are a few examples among the variety
related to climate change have referenced resilience or
of definitions. The IPCC defines adaptation as
adaptation. Federal, state, and local agencies, and other
stakeholders, often intend different meanings when they
[t]he process of adjustment to actual or expected
refer to resilience and climate change adaptation.
climate and its effects. In human systems,
adaptation seeks to moderate harm or exploit
This product presents selected definitions in use for
beneficial opportunities. In natural systems, human
resilience and climate change adaptation, and describes
intervention may facilitate adjustment to expected
trends and evolutions in use related to climate change. To
climate and its effects.… (Noble et al. 2014)
assist Congress as it considers proposals to enhance
adaptation and resilience, and exercises its appropriations
The U.S. Global Change Research Program (USGCRP), in
and oversight functions, this product seeks to clarify and
its Glossary, defines adaptation as “adjustment in natural or
identify some of the choices implied by differences among
human systems in response to a new or changing
definitions. Terms used and definitions provided in
environment that exploits beneficial opportunities or
legislation, regulation, and guidance may shape how
moderates negative effects.” The Fourth National Climate
executive agencies or the courts interpret congressional
Assessment, also associated with the USGCRP, says that
direction and its implementation. Congress may wish to
“[a]daptation refers to actions taken at the individual, local,
consider whether to clarify terms in legislation or to give
regional, and national levels to reduce risks from even
discretion to the executive branch. Statutory language may
today’s changed climate conditions and to prepare for
be broad, precise, or ambiguous.
impacts from additional changes projected for the future.”
Climate Change Adaptation and Resilience
The interagency U.S. Climate Resilience Toolkit takes a
Grammatically, adaptation is a process, action, or
narrower approach, defining adaptation as “the process of
sometimes the result of the action, whereas resilience is a
adjusting to new (climate) conditions in order to reduce
condition or capacity. In practice, the distinctions and
risks to valued assets.” The Government Accountability
relationship between the two terms are more complicated,
Office (GAO) has defined adaptation as “adjustments to
with numerous definitions used for each. A CRS review of
natural or human systems in response to actual or expected
definitions used by federal agencies and the
climate change.” The U.S. Department of Agriculture takes
Intergovernmental Panel on Climate Change (IPCC)
a slightly different approach: “Adaptation refers to the
indicates that there are notable differences between the two
process of finding ways to prepare for and flexibly respond
concepts of adaptation and resilience in the context of
to changes in climate.”
climate change. Additionally, there are differences among
entities in their definitions of a single term. The differences
The Federal Emergency Management Agency (FEMA) has
suggest potentially important nuances that may have policy
long used mitigation as “any sustained action to reduce or
and implementation consequences. Some agencies and
eliminate long-term risk to people and property from
stakeholders appear to use adaptation and resilience
natural hazards and their effects.” Although not described
interchangeably or to poorly distinguish their meanings.
as adaptation, many of FEMA’s mitigation efforts may
support adaptation to climate changes.
Over the past decade, CRS has observed a general shift
from a prevalence in federal use of the term climate change
Definitions and Uses of Resilience
adaptation to a rise in the term resilience in the context of
The IPCC, in a 2012 report on disaster risk management,
climate change. Resilience also has become more prevalent
defines resilience as “the ability of a system and its
as an objective of risk reduction more generally. The shift
component parts to anticipate, absorb, accommodate, or
in use of the terms in the context of climate change policy
recover from the effects of a potentially hazardous event in
may connote change in the concept or approach, a reduction
a timely and efficient manner…” The USGCRP Glossary
of priority for climate change adaptation, greater integration
defines resilience as “a capability to prepare for, respond to,
of climate change risk management into multi-hazard
and recover from significant multi-hazard threats with
management efforts, or political sensitivity to explicit
minimum damage to social well-being, the economy, and
references to “climate change.”
the environment.” The interagency U.S. Climate Resilience
Toolkit defines resilience as “[t]he capacity of a
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Climate Change: Defining Adaptation and Resilience, with Implications for Policy
community, business, or natural environment to prevent,
Additionally, resilience appears rarely to incorporate taking
withstand, respond to, and recover from a disruption.”
advantage of emerging opportunities in a changing climate.
Although adaptation is often associated with adjustments to
The Department of Defense (DOD) uses a general
avoid negative consequences, it is also often associated
definition of resilience when addressing climate change
with seeking opportunities and new benefits of change.
adaptation: the “ability to anticipate, prepare for, and adapt
to changing conditions and withstand, respond to, and
Implications for Congress
recover rapidly from disruptions” (DOD Directive
Generally, noting the distinctions between adaptation and
4715.21). Climate change adaptation and resilience
resilience, as in the IPCC’s definitions, can help clarify
measures are often implemented as part of DOD-wide
policy implications. Uses may continue to evolve over time.
resiliency efforts carried out by the Military Services. For
example, the Air Force approach to “installation resilience”
If Congress addresses climate change adaptation or
includes assessing and preparing for any event that could
resilience, it may clarify its intent by providing definitions,
disrupt the operations of its installations—be they manmade
or leave definitions to federal agencies, or to interpretation
accidents and attacks, or natural disasters.
by the courts if litigated. Some recent bills include
adaptation and resilience in their definitions sections.
Congress (in Section XXX of P.L. 115-254) directed
Executive agencies may promulgate definitions through
FEMA to define for its use the terms resilient and
formal means or use flexible guidance or communications.
resiliency. The agency has not completed this process.
Using the terms interchangeably may leave confusion and
create uncertainty for stakeholders as to scope and federal
Takeaways from the Variety of Definitions
intent, and may complicate Congress’s oversight and
Examination of the differences among definitions and uses
assessments of performance and effect of federal efforts.
points to elements that may be important for understanding
intentions or for decisionmaking. Some uses appear only to
If Congress addresses objectives and definitions regarding
address sudden-onset events, such as hurricanes or flash
adaptation or resilience, it would face several questions,
flooding; others would also encompass slow onset or
such as whether the term or terms used are to
chronic conditions, such as mean temperature increases,
seasonal changes (e.g., change in timing of snowmelt), or
 cover responses to sudden-onset risks or events and/or
shifting ranges of disease-bearing insects.
slow-onset risks, or both?
Climate change adaptation seems most often—but not
 apply to climate change-related risks, or to climate
always—associated with new conditions or forward-
hazards in the context of multiple hazards?
looking expectations. For both terms, when the objective is
forward-looking, adaptation may imply a longer time
 be explicit about anticipating and preparing for evolving
horizon than resilience.
future risks (i.e., use of climate change projections), or
indicate use of historical data or recent climate
Adaptation often implies altering a system to accommodate
conditions or risks?
persistent or long-term anticipated changes in the climate;
this may involve system alterations that may not be
 include making durable changes in anticipation of
necessary to enhance resilience to a static climate condition.
current or future conditions, or focus on recovery to
Resilience is sometimes (but not always) considered as
predisruption status?
withstanding a hazard with a return to predisturbance
conditions, or “bouncing back.” This can raise questions for
 allow for transformational change of the underlying
federal actions as to whether their objectives are to return a
system at risk as well as incremental change?
system to its predisaster form or function, or to transform
systems more profoundly in order to avoid risks while
 seek potentially beneficial opportunities, not just avoid
maintaining welfare or services in an evolving environment.
risks or adverse conditions?
Some in the climate change adaptation community see the
desired outcome as systems well adapted to future climate
 incorporate social aspects of adaptation and/or
conditions; this may go beyond some resilience concepts.
resilience, including capacity, equity, and other
For example, well adapted may entail removing
dimensions?
development from a high-hazard location and not merely
building hazard resilience. In other words, adaptation may
 suggest the level of acceptable risk implied in being well
favor removing structures rather than elevating them.
adapted or resilient? What is the outcome sought?
Until the 2010s, the climate change policy community used
Jane A. Leggett, Specialist in Energy and Environmental
adaptation most often as the potential process of addressing
Policy
impacts of climate change; it was less often conceived in a
context encompassing nonclimate hazards, such as
IF11827
earthquakes. In contrast, resilience is often raised within a
scope of multiple climate and nonclimate hazards, and is
often used to characterize the capacity of a system (e.g.,
community, subpopulation, business, or ecosystem).
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Climate Change: Defining Adaptation and Resilience, with Implications for Policy

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