--- - chapter_identifier: near-term-adaptation-needs-and-increased-resiliency confidence: '

There is high confidence that the amount of adaptation activity, in particular implementation activity, is increasing. There is less agreement and evidence regarding the consequences of this activity.

' evidence: "

There exists extensive documentation in the gray literature of specific adaptation planning and implementation activities underway by local, state, regional, and federal agencies and jurisdictions. The literature also contains reports that attempt to provide an overview of these activities, such as the recent set of case studies in Vogel et. al. (2017).{{< tbib '14' '3c3cc09b-c2d7-4c52-bf8f-c064efa78e93' >}} Websites, such as those of the Georgetown Climate Center (http://www.georgetownclimate.org), provide summaries and examples of adaptation activities in the United States. The sectoral and regional chapters in this National Climate Assessment also provide numerous examples of adaptation planning and implementation activities. The literature also offers work that aims to provide surveys of large numbers of adaptation activity, such as Moser et. al. (2018){{< tbib '121' 'b47b4130-ce3f-4e3e-914d-443a5652abbb' >}} and Stults and Woodruff (2016).{{< tbib '164' '44dd3160-74d0-4173-8ca4-b503fcd93615' >}}

" href: https://data.globalchange.gov/report/nca4/chapter/near-term-adaptation-needs-and-increased-resiliency/finding/key-message-28-1.yaml identifier: key-message-28-1 ordinal: 1 process: '

The scope for this chapter was determined by the Fourth National Climate Assessment (NCA4) Federal Steering Committee, which is made up of representatives from the U.S. Global Change Research Program member agencies. The scope was also informed by research needs identified in the Third National Climate Assessment (NCA3). Authors for this NCA4 chapter were selected to represent a range of public- and private-sector perspectives and experiences relevant to adaptation planning and implementation.

This chapter was developed through technical discussions of relevant evidence and expert deliberation by chapter authors during teleconferences, e-mail exchanges, and a day-long in-person meeting. These discussions were informed by a comprehensive literature review of the evidence base for the current state of adaptation in the United States. The author team obtained input from outside experts in several important areas to supplement its expertise.

' report_identifier: nca4 statement: '

Adaptation planning and implementation activities are occurring across the United States in the public, private, and nonprofit sectors. Since the Third National Climate Assessment, implementation has increased but is not yet commonplace. (High Confidence)

' uncertainties: "

While the amount of adaptation-related activity is clearly increasing, the lack of clear standards and the diverse lexicon used in different sectors make it difficult to systematically compare different adaptation activities at the level of outcomes across sectors and regions of the country. In addition, publicly available adaptation plans may never actually result in implementation. It is thus difficult to provide a quantitative assessment of the increase in adaptation activity other than just counting plans and initiatives. Given the reliance on small-sample surveys, judgments about the distribution of adaptation actions across categories have potentially large errors that are difficult to estimate. In addition, it is difficult to assess the contribution of these activities to concrete outcomes such as risk reduction or current and future improvements to well-being, security, and environmental protection.{{< tbib '130' 'dbb9cf98-a2e1-4392-b1f9-38d00259ecdf' >}} There also exists little gap analysis that compares any given set of adaptation activities with what might be appropriate according to some normative standard or what might be reasonably achieved. Thus, while adaptation activities are clearly increasing in the United States, scant evidence exists for judging their consequences.

" uri: /report/nca4/chapter/near-term-adaptation-needs-and-increased-resiliency/finding/key-message-28-1 url: ~ - chapter_identifier: near-term-adaptation-needs-and-increased-resiliency confidence: "

There is high confidence that most organizations’ planning is currently based on extensions from the record of local climate conditions.{{< tbib '169' '60233f20-d45f-4086-ada7-00dbd47712c3' >}}

" evidence: "

The assumption that the historical record of events and variability will be the same in the future is called the stationarity assumption{{< tbib '27' 'c52f2539-9c5e-4ead-b8b7-f1884c5d662e' >}} and has guided planning for climate and weather events in most places for most of recorded history. The evidence is strong that the stationarity assumption is no longer valid for all impacts and variability in all locations, because climate change is altering both the events and their variability.{{< tbib '3' '666daffe-2c3b-4e2d-9157-16b989860618' >}}^,{{}}^,{{}}^,{{}} Regional chapters in this assessment establish the climate variables for which, and the extent to which, non-stationarity has been confirmed around the United States. These chapters also provide extensive documentation of cases in which failure to adapt to current and future climate conditions can cause significant adverse impacts.

" href: https://data.globalchange.gov/report/nca4/chapter/near-term-adaptation-needs-and-increased-resiliency/finding/key-message-28-2.yaml identifier: key-message-28-2 ordinal: 2 process: '

' report_identifier: nca4 statement: '

Successful adaptation has been hindered by the assumption that climate conditions are and will be similar to those in the past. Incorporating information on current and future climate conditions into design guidelines, standards, policies, and practices would reduce risk and adverse impacts. (High Confidence)

' uncertainties: "

While significant uncertainties can exist in estimating the extent to which current variability differs from historic observations in any particular location, there is robust evidence that such differences do occur in many locations (see Ch. 18: Northeast; Ch. 19: Southeast; Ch. 20: U.S. Caribbean; Ch. 21: Midwest; Ch. 22: N. Great Plains; Ch. 23: S. Great Plains; Ch. 24: Northwest; Ch. 25: Southwest; Ch. 26: Alaska; and Ch. 27: Hawaiʻi & Pacific Islands).{{< tbib '5' '29960c69-6168-4fb0-9af0-d50bdd91acd3' >}}^,{{}}^,{{}}^,{{}} However, the development and use of analytic tools, decision-making processes, and application mechanisms built on the assumption of non-stationarity lag significantly behind the growing realization that stationarity is no longer a sound basis for long-range planning.{{< tbib '167' '19a4d709-1ec6-4e02-ba94-0d4abb4b3820' >}} Nonetheless, new techniques are being applied.{{< tbib '10' '14abc4e6-e419-4686-880f-cd2f3e28e11c' >}}^,{{}}^,{{}} For example, scenario planning can provide alternative actions that can be carried out if different impacts occur.{{< tbib '70' 'dcd195b2-6aab-4ff5-8554-db5607fd11c5' >}}^,{{}}

" uri: /report/nca4/chapter/near-term-adaptation-needs-and-increased-resiliency/finding/key-message-28-2 url: ~ - chapter_identifier: near-term-adaptation-needs-and-increased-resiliency confidence: "

Significant agreement and strong evidence provide high confidence that adaptation is a form of iterative risk management and that this is an appropriate framework for understanding, addressing, and communicating climate-related risks.{{< tbib '33' '7f8b90be-c5d1-43b5-8b7f-a485ef08c7ec' >}}

" evidence: "

Evidence from a large body of literature and observations of experience support the judgment that iterative risk management is a useful framework (e.g., National Research Council 2009, America's Climate Choices 2010, Kunreuther et al. 2012{{< tbib '142' '7ab8b14a-38c7-4128-b0e3-fe1ab65edac0' >}}^,{{}}^,{{}}). The literature also suggests its conceptual similarity with other methods that use different names.

" href: https://data.globalchange.gov/report/nca4/chapter/near-term-adaptation-needs-and-increased-resiliency/finding/key-message-28-3.yaml identifier: key-message-28-3 ordinal: 3 process: '

' report_identifier: nca4 statement: '

Adaptation entails a continuing risk management process; it does not have an end point. With this approach, individuals and organizations of all types assess risks and vulnerabilities from climate and other drivers of change (such as economic, environmental, and societal), take actions to reduce those risks, and learn over time. (High Confidence)

' uncertainties: '

The literature and practice of climate change are undergoing a process of maturation and convergence. The process began with many organizations and sectors developing their own approaches and terminology in response to climate risks, meaning that a wide variety of approaches still exist in the field. We believe that the field will progress and converge on the most effective approaches, including iterative risk management. But this convergence is still in process, and the outcome remains uncertain.

' uri: /report/nca4/chapter/near-term-adaptation-needs-and-increased-resiliency/finding/key-message-28-3 url: ~ - chapter_identifier: near-term-adaptation-needs-and-increased-resiliency confidence: '

There is suggestive evidence that provides medium confidence that many proactive adaptation actions offer significant benefits that exceed their costs. However, because of a small sample size and insufficient evaluation, it is in general hard to know the extent to which this is true in any particular case. There is strong agreement that evaluating adaptation involves consideration of a wide range of measures of social well-being.

' evidence: "

Both limited field applications and literature reviews highlight adaptation co-benefits, including those associated with equity considerations.{{< tbib '83' '971185c1-a31f-4c15-8454-57f273b4ed33' >}} Near-term benefits are assessed from observations of adaptation results, as well as from comparisons to similar situations without such responses; longer-term benefits are generally assessed from projections.

" href: https://data.globalchange.gov/report/nca4/chapter/near-term-adaptation-needs-and-increased-resiliency/finding/key-message-28-4.yaml identifier: key-message-28-4 ordinal: 4 process: '

' report_identifier: nca4 statement: '

Proactive adaptation initiatives—including changes to policies, business operations, capital investments, and other steps—yield benefits in excess of their costs in the near term, as well as over the long term (medium confidence). Evaluating adaptation strategies involves consideration of equity, justice, cultural heritage, the environment, health, and national security (high confidence).

' uncertainties: '

Benefits are based on understanding the relevant systems so that one can compare similar cases and construct counterfactuals. Such understanding is excellent for many engineered systems (for example, how a storm drain performs under various rainfall scenarios) but is less robust for many biological systems. Benefit–cost ratios can have large uncertainties associated with estimates of costs, the projection of benefits, and the economic valuation of benefits. In addition, because expected differences in benefit–cost ratios are sufficiently large and the number of current examples is sufficiently low, there are large uncertainties in applying results from one case to another.

' uri: /report/nca4/chapter/near-term-adaptation-needs-and-increased-resiliency/finding/key-message-28-4 url: ~ - chapter_identifier: near-term-adaptation-needs-and-increased-resiliency confidence: '

There is significant agreement that provides high confidence, in at least some cases, that both 1) mainstreaming climate information into existing risk management and 2) creating enabling environments and institutions to improve adaptation capacity, implementation, and evaluation reduce risk, produce co-benefits across communities and sectors, and help secure economic investments into the future.

' evidence: "

There is significant agreement, but only case study evidence, that effective adaptation can be realized by mainstreaming.{{< tbib '100' '40cd1072-ac17-4dfa-ba98-a554bf1a0458' >}}^,{{}}^,{{}} Significant evidence exists regarding the scale of longer-term adaptation required in some climate futures based on modeling studies. Significant agreement, but less direct evidence, exists on the scale of organizational and other changes needed to implement these adaptation actions.

" href: https://data.globalchange.gov/report/nca4/chapter/near-term-adaptation-needs-and-increased-resiliency/finding/key-message-28-5.yaml identifier: key-message-28-5 ordinal: 5 process: '

' report_identifier: nca4 statement: '

Integrating climate considerations into existing organizational and sectoral policies and practices provides adaptation benefits. Further reduction of the risks from climate change can be achieved by new approaches that create conditions for altering regulatory and policy environments, cultural and community resources, economic and financial systems, technology applications, and ecosystems. (High Confidence)

' uncertainties: '

It is not well understood how community acceptance of needed adaptations develops. This presents both a barrier to the implementation of adaptation measures and an opportunity for additional research into ways to close this gap in understanding. Additionally, a need exists to clarify the co-benefits of addressing multiple threats and opportunities. Effective adaptation also depends on networks of collaboration among researchers and practitioners and the long-term support of monitoring networks. The sustainability of both types of networks is a major uncertainty. Their effectiveness is both an uncertainty and major research need.

' uri: /report/nca4/chapter/near-term-adaptation-needs-and-increased-resiliency/finding/key-message-28-5 url: ~