Editing IPCC:AR6/WGII/Chapter-14 (section)

=== 14.7.2 The Solution Space ===

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==== 14.7.2.1 Incremental Adaptation, Barriers and Limits ====

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Adaptation actions to moderate the effects of climate impacts are well documented in North America and have buffered much of the past and currently observed climate impacts (e.g., [[#Lempert--2018|Lempert et al., 2018]] ; [[#Lemmen--2021|Lemmen et al., 2021]] ). While it is challenging to catalogue adaptation activities, as many are not published or are not necessarily undertaken with climate adaptation as the primary rationale ( [[IPCC:Wg2:Chapter:Chapter-1#1.3.2.2|Section 1.3.2.2]] ), most of the activities identified by sector in this chapter have been primarily incremental adaptation measures ( ''medium evidence, high agreement'' ). Many actions are extensions of existing practices for managing climate variability and there is broad agreement that worsening future conditions will exceed the capacity of many of these efforts ( [[#Kates--2012|Kates et al., 2012]] ; [[#Termeer--2017|Termeer et al., 2017]] ; [[#Fazey--2018|Fazey et al., 2018]] ; [[#Fedele--2019|Fedele et al., 2019]] ; [[#Shi--2021|Shi and Moser, 2021]] ).

Progress in adaptation planning and implementation between regions in North America is uneven (Table 14.6; see Box 14.7; [[#Bierbaum--2013|Bierbaum et al., 2013]] ; [[#Moser--2017|Moser et al., 2017]] ; Auditors General, 2018; [[#INECC%20and%20Semarnat--2018|INECC and Semarnat, 2018]] ; [[#Shi--2021|Shi and Moser, 2021]] ). At the local level (cities) in the USA, commitment of elected officials, financial resources and awareness of climate-change hazards and risks have been identified as driving the variation in climate adaptation ( [[#Shi--2015|Shi et al., 2015]] ). Adaptation programmes have come under budgetary and political pressures that limit continuity of efforts ( [[#Moss--2019|Moss et al., 2019]] ). Implementation of adaptation has also faced challenges due to institutional arrangements, constraints and gaps that prevent different levels of government, social organisations and academia to act in an integrated and timely way to consider biodiversity, agriculture and water systems (e.g., see Box 14.7; [[#Bourne--2016|Bourne et al., 2016]] ; [[#Nalau--2018|Nalau et al., 2018]] )

'''Table 14.6 |''' Adaptation trends and progress across sectors. Adaptation progress consists of assessment (A), planning (P), implementation of strategies (I) and evaluation of efficacy (E).

{| class="wikitable"
|-
! colspan="3"|
! colspan="4"| Adaptation progress

! colspan="2"| Limits

|-
! Sector

! Strategies

! Cases

! A

! P

! I

! E

! Soft

! Hard

|-
| Terrestrial ecosystems ( [[#14.5.1.1|Section 14.5.1.1]] )

| Broad use of tools such as scenario planning, structured decision making and adaptation planning frameworks

| Planning for climate refugia in the Sierra Nevada of California, USA ( [[#Morelli--2016|Morelli et al., 2016]] )

| H

| H

| L to M

| L

| Management agency internal policies which may prevent the flexibility required for implementation of adaptation strategies

| Some species may face local extirpation or even extinction if adaptive capacity is overwhelmed

|-
| Oceans ( [[#14.5.2|Section 14.5.2]] )

| Proactive and rapid management approaches to minimise impacts of increasingly frequent entanglements of protected species, caused by climate-driven changes in prey and fishery activities

| Dynamic closure areas to reduce loggerhead turtle bycatch in Hawaiian shallow-set longline fisheries ( [[#Howell--2015|Howell et al., 2015]] ; [[#Lewison--2015|Lewison et al., 2015]] ), blue whale ship-strike risk in near-real time ( [[#Hazen--2017|Hazen et al., 2017]] ; [[#Abrahms--2019a|Abrahms et al., 2019a]] ) and bycatch of multiple top predator species in a West Coast drift gillnet fishery ( [[#Hazen--2018|Hazen et al., 2018]] )

| H

| H

| M

| M

| Lack of coordination and planning at multiple scales as species redistribute across fishery areas, marine protected zones and international and jurisdictional boundaries

| Marine species mortality events

|-
| Freshwater resources ( [[#14.5.3|Section 14.5.3]] )

| Forecasting and warning of harmful algal blooms (HABs) that affect water quality

| Reduced human exposure to the increased risk of toxins from HABs in the Great Lakes

| M

| L to M

| L to M

| L to M

| Financial resources required to enhance water treatment facilities to deal with HABs, technological innovation to improve treatment and removal of HABs, closure of recreational water use

| Severe human health effects, mortality of aquatic species

|-
| Water availability ( [[#14.5.3|Section 14.5.3]] )

| Water allocation policies reassessed to enhance equity, sustainability and flexibility in times of shortage through sharing agreements, improved groundwater regulation and voluntary water transfers

| US Colorado River interstate shortage sharing agreement

| H

| H

| M

| L to M

| Complex legal and administrative challenges, heightening lengthy disputes and costly interstate legal battles

| Depletion of finite groundwater resources and reduced flow in hydrologically connected rivers

|-
| Food and fibre ( [[#14.5.4|Section 14.5.4]] )

| Improved climate resilience through increasing income and harvest/crop portfolio diversification

| Fishing communities in the US-SW and US-NE through nature-based aquaculture solutions ( [[#Messier--2019|Messier et al., 2019]] ; [[#Rogers--2019|Rogers et al., 2019]] ; [[#Young--2019|Young et al., 2019]] ; [[#Fisher--2021|Fisher et al., 2021]] )

| H

| H

| M to H

| M

| Lack of high-resolution and locally tailored climate-change information

| Collapse of fisheries and loss of crops due to excessive warming and extreme events

|-
| Cities and infrastructure ( [[#14.5.5|Section 14.5.5]] )

| Consideration of the value of green infrastructure and natural assets to meet a range of adaptation needs related to flooding, extreme urban heat, SLR and drought

| Municipal Natural Assets Initiative to assist Canadian municipalities to integrate natural assets in financial planning and asset management programmes and consider projected climate changes ( [[#Municipal%20Natural%20Assets%20Initiative--2018|Municipal Natural Assets Initiative, 2018]] )

| H

| H

| M

| L to M

| Organisations’ willingness to take on solutions that are emergent and less tested;

capacity for municipalities to undertake the development and assessment of this new infrastructure

| Rate and magnitude of climate changes exceeding capacity of natural/green infrastructure to cope

|-
| Health and communities (Sections 14.5.5, 14.5.6)

| Access to green spaces, cooler infrastructure and cooling stations

| The heatwave plan for Montreal which includes visits to vulnerable populations, cooling shelters, monitoring of heat-related illness and extended hours for public pools ( [[#Lesnikowski--2017|Lesnikowski et al., 2017]] )

| H

| H

| L to M

| L to M

| Lack of effective warning and response systems, ability to reach at-risk populations, building designs, enhanced pollution controls, urban planning strategies, and affordable, resilient health infrastructure

| Extreme increase in heat-related mortality and morbidity

|-
| Tourism and recreation ( [[#14.5.7|Section 14.5.7]] )

| Diversification of winter-focused recreation and tourism opportunities

| Investments in climate-resilient infrastructure within Canadian National Parks which have increased visitation rates during the shoulder seasons ( [[#Fisichelli--2015|Fisichelli et al., 2015]] ; [[#Lemieux--2017|Lemieux et al., 2017]] ; [[#Wilkins--2018|Wilkins et al., 2018]] )

| H

| H

| M

| L

| Social inequalities generated by the tourism development process not considered, such as increased property taxes leading to the marginalisation of local residents in favour of wealthy tourists

| Lack of precipitation that falls as snow particularly in lower-elevation areas

|-
| Commerce and transportation ( [[#14.5.8|Section 14.5.8]] )

| Improved engineering and technological solutions, in addition to innovative policy, planning, management and maintenance approaches, to enhance climate resilience for transportation and related commerce

| For roads, changing pavement mixes to be more tolerant to heat or frost heaving, expanding drainage capacity, reducing flood risks, enhancing travel advisories and alerts, elevating or relocating new infrastructure where feasible and changing infrastructure design requirements ( [[#Natural%20Resources%20Conservation%20Service--2008|Natural Resources Conservation Service, 2008]] ; [[#EPA--2017|EPA, 2017]] ; [[#Pendakur--2017|Pendakur, 2017]] )

| H

| H

| M

| L

| Lack of financial resources to build climate-resilient infrastructure, particularly in marginalised communities

| Extreme events which may cause significant and irreversible impacts on the transportation sector with major implications for supply chains and global trade

|}

Note:

L: low, M: moderate, H: high

Adaptive capacity in the face of climate risks and impacts has not been equal across North American communities ( [[#Sarkodie--2019|Sarkodie and Strezov, 2019]] ). Lack of representation, health inequities and economic constraints adversely affect the capacity to respond to change and further exacerbate marginalisation. For example, within many water basins in Canada and the USA, planning processes are often hampered by conflicting interests, asymmetrical information and differential power ( [[#ICLEI%20Canada--2016|ICLEI Canada, 2016]] ; [[#Nordgren--2016|Nordgren et al., 2016]] ; [[#Woodruff--2016|Woodruff and Stults, 2016]] ).

The absence of evidence about the current effectiveness of proposed adaptation actions to guide future actions and investments presents a serious risk to North America, especially at higher GWLs (medium confidence). Evaluating the limits to adaptation and the effectiveness of adaptation actions is hindered by a lack of monitoring and evaluation (Auditors General, 2018; [[#Dilling--2019|Dilling et al., 2019]] ; [[#Berrang-Ford--2021|Berrang-Ford et al., 2021]] ). Incremental, passive adaptations are often characterised by ''soft'' limits due to differing access to resources and by perceptions and tolerance of risk ( [[#Moser--2010|Moser, 2010]] ; [[#Dow--2013|Dow et al., 2013]] ). At current warming levels, social–ecological systems have been reaching limits to adaptation in regions with high exposure and high sensitivity ( ''medium confidence'' ). However, the implications for adaptation are unclear as soft adaptation limits are mutable and change with evolving knowledge, values, interests and perspectives involved in decision making ( [[#Adger--2009|Adger et al., 2009]] ; [[#Moser--2017|Moser et al., 2017]] ). ''Hard'' limits have been identified for some natural systems, such as species extinctions (Sections 14.5.2.1, 14.5.1.3; Table 14.2).

Adaptation actions in one place or sector can have adverse side effects elsewhere ( ''medium confidence'' ). For example, increased use of groundwater for irrigation in response to aridification can reduce baseflows into rivers with adverse impacts on stream ecology and water availability for communities far downstream ( [[#14.5.3|Section 14.5.3]] ). Additionally, across multiple sectors in North America, adaptation actions have tended to be sector specific rather than integrating across systems ( [[#Gao--2017|Gao and Bryan, 2017]] ; [[#Fulton--2019|Fulton et al., 2019]] ), despite the increasing awareness of cascading impacts and interdependencies ( [[#Zimmerman--2010|Zimmerman and Faris, 2010]] ; [[#C40%20Cities%20and%20AECOM--2017|C40 Cities and AECOM, 2017]] ) and risks from possible ecological and social thresholds that have been identified under higher GWL ( [[#14.6.3|Section 14.6.3]] ). For example, the water, energy and food nexus in North America has highlighted that food, water and energy security depend on transportation infrastructure ( [[#14.5.8.1.2|Section 14.5.8.1.2]] ; [[#Romero-Lankao--2018|Romero-Lankao et al., 2018]] ).

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==== 14.7.2.2 Adaptation Through Participatory and Robust Decision Making, Indicators and Sustained Assessments ====

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In response to some of the challenges presented in [[#14.7.2.1|Section 14.7.2.1]] , substantial progress has been made in the North American context on the development of climate services, indicators, sustained assessments, and participatory and stakeholder-driven robust decision making ( ''medium confidence'' ) ( [[#Fazey--2018|Fazey et al., 2018]] ; [[#Fedele--2019|Fedele et al., 2019]] ; [[#Moss--2019|Moss et al., 2019]] ; [[#Boon--2021|Boon et al., 2021]] ; [[#Werners--2021|Werners et al., 2021]] ).

Decision making related to adaptation policies, plans and projects has become more formalised, emphasising participatory governance and co-production of knowledge. Canada has improved capacity with its Canadian Expert Panel on Climate Change Adaptation and Resilience Results and the recent National Adaptation Plan ( [[#14.7.1|Section 14.7.1.5]] ), with the development of a series of indicators to measure progress on adaptation ( [[#EPCCAR--2018|EPCCAR, 2018]] ; [[#Government%20of%20Canada--2021a|Government of Canada, 2021a]] ). In the USA, indicators have been developed to communicate climate risks and guide adaptation efforts from federal ( [[#Kenney--2020|Kenney et al., 2020]] ) to more regional initiatives ( [[#Kenney--2021|Kenney and Gerst, 2021]] ). These climate indicators have been used to support user-driven assessments and to articulate adaptation goals ( [[#Moss--2019|Moss et al., 2019]] ; [[#Kenney--2020|Kenney et al., 2020]] ); however, these frameworks have not sufficiently incorporated monitoring and evaluation into adaptation plans ( [[#Lempert--2018|Lempert et al., 2018]] ; [[#Kenney--2020|Kenney et al., 2020]] ). Tools and services to facilitate risk assessment and action planning have been made available through federal government climate service efforts, and guidance for their use has been developed ( [[#Vano--2018|Vano et al., 2018]] ); however, these products have been characterised as insufficiently developed to allow all adaptation practitioners to use these services ( [[#Meerow--2017|Meerow and Mitchell, 2017]] ).

Throughout North America, co-development (or co-production) of adaptation efforts among stakeholders who share common climate vulnerabilities or risk levels (e.g., individuals, groups, communities, businesses or institutions) has been a core attribute of adaptation planning ( [[#Mees--2016|Mees et al., 2016]] ) and ranges across many sectors (e.g., Sections 14.5.2.2, 14.5.3.3, 14.5.4.3). Participatory efforts and robust decision making have also been observed; some integrated watershed planning processes have high degrees of sustained stakeholder involvement ( [[#14.5.3.3|Section 14.5.3.3]] ; FAQ 14.4; [[#Harris-Lovett--2015|Harris-Lovett et al., 2015]] ; [[#Cantú--2016|Cantú, 2016]] ).

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==== 14.7.2.3 Transformational Adaptation and Climate Resilience ====

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Climate change and its projected impacts pose a substantial risk to North America as a region as well as to sectors, communities and individuals ( [[#14.6.2|Section 14.6.2]] ). Incorporating different values and knowledge systems, consideration of equity and justice as core objectives and addressing underlying vulnerabilities are principles that can guide transformational adaptation and resilience ( ''medium confidence'' ).

Approaches that advance adaptation within the existing contexts (finances, institutions and processes) have been increasingly promoted by governments to mainstream climate risk into all considerations ( [[#Rosenzweig--2014|Rosenzweig and Solecki, 2014]] ; [[#Van%20der%20Brugge--2015|Van der Brugge and Roosjen, 2015]] ; [[#Boon--2021|Boon et al., 2021]] ; [[#Shi--2021|Shi and Moser, 2021]] ). Policies and programmes that build upon existing approaches that have inherent climate resilience including Indigenous knowledge-based land and resource management ( [[#14.5.4|Section 14.5.4]] ), co-management of agriculture and freshwater resources ( [[#14.5.3|Section 14.5.3]] ), NbS (see Box 14.7), links between health and equity, and ecosystem-based management (Sections 14.5.2–14.5.4) have advanced sustainable and equitable climate resilience. Implementing the recommendations in the ASCE committee’s report on adaptation to a changing climate (2018a) and Canada’s Infrastructure and Buildings Working Group report has been identified as an opportunity to improve social equity by ensuring the resilience of infrastructure and the services it provides, through adoption of standards and good asset management practices (Amec Foster Wheeler Environment and Infrastructure, 2017; [[#ASCE--2018a|ASCE, 2018a]] ).

Long-term policy signals to incentivise ongoing, scalable adaptation action that is coordinated with mitigation efforts will increase actions and prevent potential maladaptive investment (Moser, 2018; Shi and Moser 2021). Using SDG goals and the NDCs as a framework for inclusive and coordinated partnership and vertical integration across subnational, national and regional planning can promote climate resilient development (CRD) ( [[IPCC:Wg2:Chapter:Chapter-18#18.1.3|Section 18.1.3]] ). Coordination of policies and responses have been identified as supporting longer-term, transformational adaptation and minimising risk ( [[#Termeer--2017|Termeer et al., 2017]] ; [[#Fazey--2018|Fazey et al., 2018]] ). New approaches for enabling and incentivising transformative adaptation in North America are rapidly emerging (Colloff et al. 2017; Fedel et al. 2019; Werners et al. 2021). Evaluation of the feasibility of evolving adaptation strategies is only in the early stages, but recent work has provided the foundation for assessing these considerations (Table 14.7; Chapter 16).

Differing values, perspectives, interests and needs of relevant actors ( [[#Dittrich--2016|Dittrich et al., 2016]] ) through participatory processes, such as co-production of knowledge ( [[#Meadow--2015|Meadow et al., 2015]] ; [[#Wall--2017|Wall et al., 2017]] ), have been incorporated through the Resilience Dialogues 21 [[#footnote-004|17]] and the development of guidance on climate scenarios ( [[#Chaumont--2014|Chaumont, 2014]] ). Framing of adaptation goals strongly determines beneficiaries of resultant policies and underscores the importance of a plurality of perspectives in adaptation governance ( [[#Cochran--2013|Cochran et al., 2013]] ; [[#Plummer--2013|Plummer, 2013]] ; [[#Allison--2015|Allison and Bassett, 2015]] ; [[#Raymond-Yakoubian--2018|Raymond-Yakoubian and Daniel, 2018]] ). Sustained engagement through iterative knowledge development, learning and negotiation has been identified as core for addressing climate risks ( [[#Kates--2012|Kates et al., 2012]] ; [[#Seijger--2014|Seijger et al., 2014]] ). Interdisciplinary and inclusive adaptation programmes that embrace and plan for conflict and resolution, and address inequalities, have been part of broadening the opportunities for engagement ( [[#Cantú--2016|Cantú, 2016]] ; [[#Termeer--2017|Termeer et al., 2017]] ; [[#Parlee--2018|Parlee and Wiber, 2018]] ; [[#Sterner--2019|Sterner et al., 2019]] ; [[#Haasnoot--2020|Haasnoot et al., 2020]] ).

Equity and justice in climate adaptation have been identified as providing a foundation for resilience in natural, social and built systems ( [[#Cochran--2013|Cochran et al., 2013]] ; [[#Reckien--2017|Reckien et al., 2017]] ; [[#Schell--2020|Schell et al., 2020]] ). This approach recognises that social vulnerability undermines efforts to increase adaptive capacity and that adaptation may also entrench existing social inequities, such as marginalisation of communities of colour, gender discrimination, legacy effects of colonisation and gentrification of coastal communities ( [[#Schell--2020|Schell et al., 2020]] ; [[#Thomas--2020|Thomas, 2020]] ). Thus, identifying systemic racism and the effects of colonialism within and across institutions has also been identified as part of achieving more just and equitable adaptation (Shi and Moser 2021). Acknowledgement and incorporation of IK in adaptation planning and implementation also recognises Indigenous sovereignty issues and the importance of the equitable role of Indigenous self-determination in governance and planning (see Box 14.1; [[#14.4|Section 14.4]] ; [[#Raymond-Yakoubian--2018|Raymond-Yakoubian and Daniel, 2018]] ).

Strategies have been emerging to facilitate progress by including specific guidance on tools for financing and funding climate-change adaptation infrastructure ( [[#Berry--2015|Berry and Danielson, 2015]] ; [[#Chen--2016|Chen et al., 2016]] ; [[#Zerbe--2019|Zerbe, 2019]] ). This includes facilitating transitions between incremental and transformational efforts to facilitate CRD (Figure 14.12; Chapter 18).

The extent to which resilient infrastructure contributes to social justice and equity has also been taken into consideration ( [[#Climate-Safe%20Infrastructure%20Working%20Group--2018|Climate-Safe Infrastructure Working Group, 2018]] ; [[#Doorn--2019|Doorn, 2019]] ). Proactive actions focused on small towns and rural areas—including the interdependencies between cities and surrounding areas—increases the potential that small and medium cities can build adaptive capacity at a pace that is commensurate with present and future risks ( [[#Moss--2019|Moss et al., 2019]] ; [[#Vodden--2021|Vodden and Cunsolo, 2021]] ). This coordination also creates greater opportunity for translation of knowledge into practice and assessing knowledge in the context that it is to be applied to improve decision making across scales ( [[#Enquist--2017|Enquist et al., 2017]] ; [[#Moss--2019|Moss et al., 2019]] ).

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'''Box 14.7 | Nature-based Solutions to Support Adaptation to Climate Change'''
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Nature-based Solutions (NbS) are ‘actions to protect, sustainably manage, and restore natural or modified ecosystems, that address societal challenges effectively and adaptively, simultaneously providing human well-being and biodiversity benefits’ ( [[#IUCN--2016|IUCN, 2016]] ). Such NbS in the context of climate change, or nature-based adaptation see (Box 1.3), can jointly address multiple social–ecological issues related to climate-change hazards, impacts, adaptation and mitigation (Figure Box 14.7.1; Cross-Chapter Box NATURAL in Chapter 2). Successful nature-based adaptation draws from existing adaptation approaches ( [[#Borsje--2011|Borsje et al., 2011]] ; [[#Temmerman--2013|Temmerman et al., 2013]] ; [[#Law--2018|Law et al., 2018]] ; [[#Reguero--2018|Reguero et al., 2018]] ; [[#Buotte--2019|Buotte et al., 2019]] ) and is applied across ecological and human systems ( ''high confidence'' ) (Table Box 14.7.1; Figure Box 14.7.1).

[[File:fb6015b826b52fdb95ad5281266e49b5 IPCC_AR6_WGII_Figure_14_Box_14_7_1.png]]

'''Figure Box 14.7.1 |''' '''Climate hazard protection services provided by Nature-based Solutions'''

Through a capacity to evolve to keep pace with climate change, these approaches can impart self-sustaining and cost-efficient long-term protection in addition to serving as biodiverse, carbon sinks ( [[#Scyphers--2011|Scyphers et al., 2011]] ; [[#Cheong--2013|Cheong et al., 2013]] ; [[#Temmerman--2013|Temmerman et al., 2013]] ; [[#Rodriguez--2014|Rodriguez et al., 2014]] ; [[#Herr--2016|Herr and Landis, 2016]] ; [[#Sasmito--2016|Sasmito et al., 2016]] ; [[#Reguero--2018|Reguero et al., 2018]] ). Nature-based adaptation is generally less expensive and strengthens over time, as compared with built infrastructure which ''erodes'' with time ( ''medium confidence'' ) ( [[#Narayan--2016|Narayan et al., 2016]] ; [[#Smith--2017|Smith et al., 2017]] ; [[#Sutton-Grier--2018|Sutton-Grier et al., 2018]] ). Analysis of the impacts of Hurricane Sandy determined that communities located behind wetlands experienced 20% less damage ( [[#Narayan--2016|Narayan et al., 2016]] ). Coral reefs are providing 544 million USD yr −1 ( [[#Beck--2018a|Beck et al., 2018a]] ) and mangroves 22 billion USD yr −1 in property protection for coastal communities in the USA and Mexico ( [[#Beck--2018b|Beck et al., 2018b]] ). By 2030, flooding from changes in storms, SLR (based on RCP8.5) and increases in built infrastructure in the US Gulf Coast may result in net economic losses of up to 176 billion USD, of which 50 billion USD could be avoided through implementation of nature-based measures including wetland and oyster reef restoration and other green infrastructure (see Box 14.4; [[#14.5.2|Section 14.5.2]] ; [[#EPA--2015b|EPA, 2015b]] ; [[#Reguero--2018|Reguero et al., 2018]] ).

Innovative approaches in Canada ( [[#Borsje--2011|Borsje et al., 2011]] ; [[#Spalding--2014|Spalding et al., 2014]] ; [[#Soto-Navarro--2020|Soto-Navarro et al., 2020]] ) and the USA ( [[#Law--2018|Law et al., 2018]] ; [[#Buotte--2019|Buotte et al., 2019]] ; [[#Soto-Navarro--2020|Soto-Navarro et al., 2020]] ) have led to social and environmental co-benefits and could address both future climate risk and long-standing social injustices ( [[#Hobbie--2020|Hobbie and Grimm, 2020]] ; [[#Schell--2020|Schell et al., 2020]] ; [[#Cousins--2021|Cousins, 2021]] ). Effective nature-based adaptation requires a well-coordinated suite of adaptation efforts (e.g., assessment, planning, funding, implementation and evaluation) that is co-produced among stakeholders and across sectors ( ''high confidence'' ) ( [[#Millar--2015|Millar and Stephenson, 2015]] ; [[#Kabisch--2016|Kabisch et al., 2016]] ; [[#Dilling--2019|Dilling et al., 2019]] ; [[#Morecroft--2019|Morecroft et al., 2019]] ; [[#Lavorel--2020|Lavorel et al., 2020]] ). Evaluating the efficacy of nature-based adaptation may become more tractable with more uniform guidelines for implementation ( [[#Scarano--2017|Scarano, 2017]] ; [[#Malhi--2020|Malhi et al., 2020]] ; [[#Seddon--2020|Seddon et al., 2020]] ), and coordination in scaling-up local-level nature-based adaptation measures is likely to facilitate long-term success ( [[#Gao--2017|Gao and Bryan, 2017]] ).

'''Table Box 14.7.1 |''' Nature-based adaptation in North America

{| class="wikitable"
|-
! Sector

! NbS actions

! Benefits

! References

|-
| rowspan="2"| Coasts

| Conservation and restoration of barrier habitats, salt marshes, mangroves, coral and oyster reefs, sand dunes and river deltas; combined natural and built infrastructure (e.g., oyster reef in front of breakwall)

| Wave attenuation; erosion and flood reduction from storm events exacerbated by SLR; novel, created habitats, connectivity; recreation, quality of life

| [[#Borsje--2011|Borsje et al. (2011)]] ; [[#Scyphers--2011|Scyphers et al. (2011)]] ; [[#Cheong--2013|Cheong et al. (2013)]] ; Pinsky et al. (2013a); [[#Temmerman--2013|Temmerman et al. (2013)]] ; [[#Ferrario--2014|Ferrario et al. (2014)]] ; [[#Möller--2014|Möller et al. (2014)]] ; [[#Rodriguez--2014|Rodriguez et al. (2014)]] ; [[#Spalding--2014|Spalding et al. (2014)]] ; [[#Yates--2014|Yates et al. (2014)]] ; [[#EPA--2015b|EPA (2015b)]] ; Grenier et al. (2015); [[#Brandon--2016|Brandon et al. (2016)]] ; [[#Herr--2016|Herr and Landis (2016)]] ; [[#Narayan--2016|Narayan et al. (2016)]] ; [[#Sasmito--2016|Sasmito et al. (2016)]] ; [[#Ward--2016|Ward et al. (2016)]] ; [[#Aerts--2018|Aerts et al. (2018)]] ; [[#Beck--2018a|Beck et al. (2018a)]] ; [[#Morris--2018b|Morris et al. (2018b)]] ; [[#Moudrak--2018|Moudrak et al. (2018)]] ; [[#Reguero--2018|Reguero et al. (2018)]] ; [[#Sutton-Grier--2018|Sutton-Grier et al. (2018)]]

|-
| Watershed approaches such as protecting and restoring forests and wetlands in coastal watersheds, adopting stream buffers in agricultural areas (see agriculture below)

| Creation of a less flashy/variable hydrology; reduction in sediment, nutrient, hazardous chemical input to coastal waters and reduction in eutrophication and other water quality impairments, notably in deep waters where fish seek refuge from rising sea surface temperatures

| [[#Deutsch--2015b|Deutsch et al. (2015b)]] ; [[#Boesch--2019|Boesch (2019)]] ; [[#CENR--2010|CENR (2010)]]

|-
| Aquaculture

| Controlled culture of fish, bivalves, corals and other marine species

| Enhancement and restoration of, and reduction in pressure on, wild species and ecosystems; restoration of threatened species such as coral reef species; storage of carbon

| Froehlich et al. (2017); [[#Reid--2019|Reid et al. (2019)]] ; [[#Theuerkauf--2019|Theuerkauf et al. (2019)]]

|-
| Agriculture

| Re-vegetation of stream buffer zones; planting of winter cover crops; wetland protection and restoration; agroforestry

| Self-sustaining and cost-efficient long-term protection from soil erosion; maintenance and enhancement of crop yields; enhancement of carbon sinks; enhancement of biodiversity; reduction in nutrient input to coasts

| [[#CENR--2010|CENR (2010)]] ; [[#Boesch--2019|Boesch (2019)]] ; [[#Seddon--2020|Seddon et al. (2020)]]

|-
| Urban areas

| Replacement of impervious surfaces with permeable pavement, green space, parks, wetlands and green infrastructure (e.g., stormwater ponds, bioswales, rain gardens, green roofs); community gardens and urban forests; restoration of natural habitats

| Reduction in urban heat island effects and air pollution; self-sustaining and cost-efficient long-term protection from flooding, erosion and SLR; enhancement of carbon sequestration biodiversity, habitat and connectivity; improvement in quality of life and human health benefits

| [[#Hobbie--2020|Hobbie and Grimm (2020)]] ; [[#Brown--2021|Brown et al. (2021)]]

|-
| rowspan="4"| Terrestrial

| Forest conservation based on productivity and vulnerability to drought and fire; longer harvest rotations

| Increase in carbon storage and biodiversity

| [[#Law--2018|Law et al. (2018)]] ; [[#Buotte--2020|Buotte et al. (2020)]] ; [[#Soto-Navarro--2020|Soto-Navarro et al. (2020)]] ; [[#Mori--2021|Mori et al. (2021)]]

|-
| Forest thinning; prescribed burning; cultural burning

| Reduction in wildfire risk and severity; increase in forest resilience to fire; reduction in forest drought stress; increase in carbon storage

| See Box 14.2 and citations therein.

|-
| Protection and restoration of natural forests

| Regulation of stream flow; reduction in soil erosion; protection and enhancement of biodiversity

| [[#Lawler--2020|Lawler et al. (2020)]] ; [[#Seddon--2020|Seddon et al. (2020)]]

|-
| Beaver ( ''Castor canadensis'' ) reintroduction

| Regulation of seasonal stream flow

| [[#McKelvey--2018|McKelvey and Buotte (2018)]] ; [[#Vose--2018|Vose et al. (2018)]]

|-
| Freshwater

| Forests to Faucets and other watershed restoration projects for stream and drinking water protection

| Improvement in water quality; reduction in drinking water treatment costs; increase in, and regulation of, streamflow

| [[#Gartner--2017|Gartner et al. (2017)]] ; [[#Claggett--2018|Claggett and Morgan (2018)]] ; [[#Price--2018|Price and Heberling (2018)]]

|}

Box 14.7

Box 14.7

<div id="FAQ" class="h2-container"></div>

<span id="faq-14.4-what-are-some-effective-strategies-for-adapting-to-climate-change-that-have-been-implemented-across-north-america-and-are-there-limits-to-our-ability-to-adapt-successfully-to-future-change"></span>