Editing IPCC:AR6/WGII/Chapter-16 (section)

=== 16.3.2 Adaptation-Related Responses by Human Systems ===

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The literature that seeks to assess adaptation progress is growing at the global ( [[#Berrang-Ford--2021a|Berrang-Ford et al., 2021a]] ), regional ( [[#Bowen--2015|Bowen and Ebi, 2015]] ; [[#England--2018|England et al., 2018]] ; [[#Robinson--2018a|Robinson, 2018a]] ; [[#Wirehn--2018|Wirehn, 2018]] ; [[#Olazabal--2019|Olazabal et al., 2019]] ; [[#Thomas--2019a|Thomas et al., 2019a]] ; [[#Biesbroek--2020|Biesbroek et al., 2020]] ; [[#Canosa--2020|Canosa et al., 2020]] ; [[#Robinson--2020b|Robinson, 2020b]] ), national ( [[#Hegger--2017|Hegger et al., 2017]] ; [[#Lesnikowski--2019a|Lesnikowski et al., 2019a]] ; [[#Lesnikowski--2019b|Lesnikowski et al., 2019b]] ) and municipal ( [[#Araos--2016|Araos et al., 2016]] ; [[#Reckien--2018|Reckien et al., 2018]] ; [[#Reckien--2019|Reckien et al., 2019]] ; [[#Lesnikowski--2020|Lesnikowski et al., 2020]] ; [[#Singh--2021|Singh et al., 2021]] ) levels, using National Communications ( [[#Gagnon-Lebrun--2007|Gagnon-Lebrun and Agrawala, 2007]] ; [[#Lesnikowski--2015|Lesnikowski et al., 2015]] ; [[#Muchuru--2017|Muchuru and Nhamo, 2017]] ), local climate change action plans ( [[#Regmi--2016b|Regmi et al., 2016b]] ; [[#Regmi--2016a|Regmi et al., 2016a]] ; [[#Reckien--2018|Reckien et al., 2018]] ; [[#Reckien--2019|Reckien et al., 2019]] ), adaptation project proposals, and reported adaptations in the peer-reviewed literature. There remains persistent publication bias in the evidence base on adaptation given the difficulty of integrating diverse knowledge sources (see [[#16.3.3|Section 16.3.3]] ). To better assess how adaptation is occurring in human systems, we draw on this literature base and characterise evidence of adaptation across regions and sectors in terms of five key questions (Table 16.4, [[#Ford--2013|Ford et al., 2013]] ; [[#Biagini--2014|Biagini et al., 2014]] ; [[#Ford--2015a|Ford et al., 2015a]] ; [[#Bednar--2018|Bednar and Henstra, 2018]] ; [[#Reckien--2018|Reckien et al., 2018]] ; [[#Tompkins--2018|Tompkins et al., 2018]] ): What types of hazards are motivating adaptation-related responses? Who is responding? What types of responses are being documented? What evidence is available on adaptation effectiveness, adequacy and risk reduction? To characterise evidence that adaptation responses indicate transformation, we use a typology based on four dimensions of climate adaptation: scope, depth, speed, and consideration of limits to adaptation ( [[#16.4|Section 16.4]] , [[#Termeer--2017|Termeer et al., 2017]] ; [[#Berrang-Ford--2021a|Berrang-Ford et al., 2021a]] ).

'''Table 16.4 |''' Key constraints associated with limits to adaptation for regions

{| class="wikitable"
|-
! Region

! Key constraints associated with limits to adaptation

|-
| Africa

| Financial constraints inhibit implementation of a variety of adaptation strategies including ecosystem-based adaptation ( [[IPCC:Wg2:Chapter:Chapter-9#9.11.4|Section 9.11.4.2]] ) and adoption of drought-tolerant crops by farmers ( [[IPCC:Wg2:Chapter:Chapter-9#9.12.3|Section 9.12.3]] ).

Information constraints (including limited climate science information), governance constraints (such as communication disconnects between national, district and community levels) and human capacity constraints (limited capacities to analyse threats and impacts) are identified as negatively affecting the implementation of adaptation policies ( [[IPCC:Wg2:Chapter:Chapter-9#9.1|Section 9.1]] 3.1).

Social/cultural constraints (social status, caste and gender) also affect adaptation in contexts with deep-rooted traditions ( [[IPCC:Wg2:Chapter:Chapter-9#9.12|Section 9.12.4]] ).

|-
| Asia

| Governance, human capacity, financial and informational constraints commonly present barriers to urban adaptation ( [[IPCC:Wg2:Chapter:Chapter-10#10.4.6.5|Section 10.4.6.5]] ).

Economic, governance, financial and informational constraints are related to both soft and hard limits to adaptation against a range of hazards in South Asia (Box 10.7), while in West Asia, physical constraints to heatwaves and drought have been associated with limits to adaptation (Box 10.7).

|-
| Australasia

| A range of constraints, including governance, information and awareness, social/cultural, human capacity and financial, have been identified as impeding adaptation action in the region ( [[IPCC:Wg2:Chapter:Chapter-11#11.7.2|Section 11.7.2]] , Box 11.1).

Evidence of limits to adaptation are primarily for ecosystems (Sections 11.7.2, 11.6), although individuals and communities are also approaching soft limits owing to social constraints ( [[IPCC:Wg2:Chapter:Chapter-11#11.7.2|Section 11.7.2]] ).

|-
| Central and South America

| Financial, governance, knowledge, biophysical and social/cultural constraints identified as most significant for adaptation ( [[IPCC:Wg2:Chapter:Chapter-12#12.5|Section 12.5]] , Table 12.3).

Soft limits are largely related to governance constraints, while evidence of hard limits is related to biophysical constraints, such as glacier shrinking leading to loss of livelihoods and cultural values ( [[IPCC:Wg2:Chapter:Chapter-12#12.5.3.4|Section 12.5.3.4]] ).

|-
| Europe

| Key constraints are identified as technical, biophysical, economic and social ( [[IPCC:Wg2:Chapter:Chapter-13#13.6.2.4|Section 13.6.2.4]] ).

For cities, settlements and key infrastructure, technical socioeconomic and environmental and regulatory constraints may lead to limits at a range of spatial scales (Figure 13.12).

Biophysical constraints may lead to limits to the ability of water saving and water efficiency measures to prevent water insecurity under high warming scenarios ( [[IPCC:Wg2:Chapter:Chapter-13#13.2.2.2|Section 13.2.2.2]] ).

|-
| North America

| Social/cultural, governance, financial, knowledge and biophysical constraints are identified as most significant for adaptation and leading to both soft and hard limits (Sections 14.5.2.1, 14.6, 14.6.2.1, Table 14.8).

|-
| Small islands

| Financial, governance, information/awareness, technological, cultural and human capacity constraints are identified as affecting adaptation and leading to soft limits (Sections 15.5.3, 15.5.4, 15.6.1, 15.6.3, 15.6.4).

Differences between constraints and soft limits in the small island context is marginal, with policymakers in the Caribbean and Indian Oceans seeing these as synonymous ( [[IPCC:Wg2:Chapter:Chapter-15#15.6.1|Section 15.6.1]] ).

|}

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[[File:f3c8985143059df6085c28fbf653c24f IPCC_AR6_WGII_Figure_16_003.png]]

'''Figure 16.3 |''' '''Salience of different types of hazards in the scientific literature on adaptation-related responses (''' '''i.''' '''e., responses that people undertake to reduce risk from climate change and associated hazards).''' Updated from a systematic review of 1682 scientific publications (2013–2019) reporting on adaptation-related responses in human systems ( [[#Berrang-Ford--2021a|Berrang-Ford et al., 2021a]] ). Numbers in table reflect the number of publications reporting. Darker colours denote more extensive reporting on a hazard as a motivating factor for the response. Publications are counted in all relevant regions or sectors.

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==== 16.3.2.1 What Hazards Are Motivating Adaptation-Related Responses? ====

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Drought and precipitation variability are the most prevalent hazards in the adaptation literature, particularly in the context of food and livelihood security. Adaptation frequently occurs in response to specific rapid or slow-onset physical events that can have adverse impacts on people. In some cases, people adapt in anticipation of climate change in general or to take advantage of new opportunities created by hazards (e.g., increased navigability due to melting sea ice). There is evidence that prior experience with hazards increases adaptation response ( [[#Barreca--2015|Barreca et al., 2015]] ). Following drought and precipitation variability, the next specific hazards that are most frequently documented in the global adaptation literature are heat and flooding. Heat, while less salient, appears to be a driver of adaptation across all regions and sectors (Stone Jr et al., 2014; [[#Hintz--2018|Hintz et al., 2018]] ; [[#Nunfam--2018|Nunfam et al., 2018]] ). Drought, extreme precipitation, and inland flooding are commonly reported in the context of water and sanitation ( [[#Bauer--2015|Bauer and Steurer, 2015]] ; [[#Lindsay--2018|Lindsay, 2018]] ; [[#Kirchhoff--2019|Kirchhoff and Watson, 2019]] ; [[#Hunter--2020|Hunter et al., 2020]] ; [[#Simpson--2020|Simpson et al., 2020]] ). Flooding is frequently reported as a key hazard for adaptation in cities, followed by drought, precipitation variability, heat, and SLR ( [[#Broto--2013|Broto and Bulkeley, 2013]] ; [[#Araos--2016|Araos et al., 2016]] ; [[#Georgeson--2016|Georgeson et al., 2016]] ; [[#Mees--2017|Mees, 2017]] ; [[#Reckien--2018|Reckien et al., 2018]] ; [[#Hunter--2020|Hunter et al., 2020]] ).

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==== 16.3.2.2 Who Is Responding? ====

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'''''Individuals and households play a central role in adaptation globally.''''' The most frequently reported actors engaged in adaptation-related responses in the scientific literature are individuals and households, particularly in the Global South (Figure 16.4). Regionally, household- and individual-level adaptation is documented most extensively in Africa and Asia, and to a lesser but still substantial extent in North America (Figure 16.4).

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[[File:3e95194749b90cfce1349af0f92eced4 IPCC_AR6_WGII_Figure_16_004.png]]

'''Figure 16.4 |''' '''Who is responding, by geographic region and sector? Cell contents indicate the number of publications reporting engagement of each actor in adaptation-related responses.''' Darker colours denote a high number of publications. Based on a systematic review of 1682 scientific publications (2013–2019) reporting on adaptation-related responses in human systems ( [[#Berrang-Ford--2021a|Berrang-Ford et al., 2021a]] ). SIS, Small Island States; Terr, terrestrial and freshwater ecosystems.

'''''National and local governments are also frequently engaged in reported adaptation across most regions.''''' In Africa and Asia, reported adaptations have been primarily associated with individuals, households, national governments, non-governmental organisations (NGOs), and international institutions, with more limited reporting of involvement from sub-national governments or the private sector ( [[#Ford--2015a|Ford et al., 2015a]] ; [[#Ford--2015|Ford and King, 2015]] ; [[#Hunter--2020|Hunter et al., 2020]] ). Engagement by sub-national governments in adaptation is more frequently documented in Europe and North America ( [[#Craft--2013|Craft and Howlett, 2013]] ; [[#Craft--2013|Craft et al., 2013]] ; [[#Bauer--2014|Bauer and Steurer, 2014]] ; [[#Lesnikowski--2015|Lesnikowski et al., 2015]] ; [[#Shi--2015|Shi et al., 2015]] ; [[#Austin--2016|Austin et al., 2016]] ). Reporting of private sector engagement is generally low. Civil society participation in adaptations is reported across all regions. Consistent with this, local governments are also widely reported in documented adaptation responses, particularly where municipal jurisdiction is high, including cities, infrastructure, water and sanitation.

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==== 16.3.2.3 What Types of Responses Are Documented? ====

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'''''Behavioural change is the most common form of adaptation.''''' The scientific literature presents extensive evidence of behavioural adaptation—change in the strategies, practices and actions that people, particularly individuals and households, undertake to reduce risk (Figure 16.5). This includes, for example, household measures to protect homes from flooding, protect crops from drought, relocation out of hazard zones, and shifting livelihood strategies ( [[#Porter--2014|Porter et al., 2014]] ). This is followed by adaptation via technological innovation and infrastructural development, nature-based adaptation (enhancing, protecting or promoting ecosystem services) and institutional adaptation (enhancing multi-level governance or institutional capabilities). Behavioural adaptation is most frequently documented in Asia, Africa and Small Island States, and in the agriculture, health and development sectors. In the agricultural sector, households are adopting or changing to crops and livestock that are more adapted to drought, heat, moisture, pests and salinity ( [[#Arku--2013|Arku, 2013]] ; [[#Kattumuri--2017|Kattumuri et al., 2017]] ; [[#Wheeler--2019|Wheeler and Marning, 2019]] ). Studies in Africa and Asia have documented shifts in farming and animal husbandry practice ( [[#Arku--2013|Arku, 2013]] ; [[#Garcia%20de%20Jalon--2016|Garcia de Jalon et al., 2016]] ; [[#Gautier--2016|Gautier et al., 2016]] ; [[#Chengappa--2017|Chengappa et al., 2017]] ; [[#Epule--2017|Epule et al., 2017]] ; [[#Kattumuri--2017|Kattumuri et al., 2017]] ; [[#Abu--2018|Abu and Reed, 2018]] ; [[#Asadu--2018|Asadu et al., 2018]] ; [[#Haeffner--2018|Haeffner et al., 2018]] ; [[#Shaffril--2018|Shaffril et al., 2018]] ; [[#Wiederkehr--2018|Wiederkehr et al., 2018]] ; [[#Zinia--2018|Zinia and McShane, 2018]] ; [[#Currenti--2019|Currenti et al., 2019]] ; [[#Fischer--2019a|Fischer, 2019a]] ; [[#Fischer--2019b|Fischer, 2019b]] ; [[#Schofield--2019|Schofield and Gubbels, 2019]] ; [[#Sereenonchai--2019|Sereenonchai and Arunrat, 2019]] ; [[#Wheeler--2019|Wheeler and Marning, 2019]] ; [[#Mayanja--2020|Mayanja et al., 2020]] ). In Small Island Nations, studies have documented household flood protections measures such as raising elevation of homes and yards, creating flood barriers, improving drainage, moving belongings and, in some cases, relocating ( [[#Middelbeek--2014|Middelbeek et al., 2014]] ; [[#Currenti--2019|Currenti et al., 2019]] ; [[#Klock--2019|Klock and Nunn, 2019]] ).

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[[File:e27d2f40735a605dec7a2baab71aebce IPCC_AR6_WGII_Figure_16_005.png]]

'''Figure 16.5 |''' '''Type of adaptation responses by global region.''' Percentages reflect the number of articles mentioning each type of adaptation over the total number of articles for that region. Radar values do not total 100% per region since publications frequently report multiple types of adaptation; for example, construction of drainage systems (infrastructural), changing food storage practices by households (behavioural), and planting of tree cover in flood-prone areas (nature-based) in response to flood risk to agricultural crops. Data updated and adapted from [[#Berrang-Ford--2021a|Berrang-Ford et al. (2021a)]] , based on 1682 scientific publications reporting on adaptation-related responses in human systems.

'''''The mix of adaptation response types differs across regions and sectors.''''' Technological and infrastructural responses are widely reported in Europe, and globally in the context of cities and water and sanitation ( [[#Mees--2017|Mees, 2017]] ; [[#Hintz--2018|Hintz et al., 2018]] ). Responses to flood risk in Europe include the use of flood- and climate-resistant building materials, large-scale flood management, and water storage and irrigation systems ( [[#van%20Hooff--2015|van Hooff et al., 2015]] ; [[#Mees--2017|Mees, 2017]] ). Technological and infrastructural responses are also documented to some extent in agriculture, including, for example, breeding more climate-resilient crops, precision farming and other high-tech solutions such as genetic modification ( [[#Makhado--2014|Makhado et al., 2014]] ; [[#Fisher--2015|Fisher et al., 2015]] ; [[#Costantini--2020|Costantini et al., 2020]] ; [[#Fraga--2021|Fraga et al., 2021]] ; [[#Grusson--2021|Grusson et al., 2021]] ; [[#Naulleau--2021|Naulleau et al., 2021]] ). While less common, institutional responses are more prominent in North America and Australasia as compared with other regions, and include zoning regulations, new building codes, new insurance schemes, and coordination mechanisms ( [[#Craft--2013|Craft and Howlett, 2013]] ; [[#Craft--2013|Craft et al., 2013]] ; [[#Parry--2014|Parry, 2014]] ; [[#Ford--2015b|Ford et al., 2015b]] ; [[#Beiler--2016|Beiler et al., 2016]] ; [[#Lesnikowski--2016|Lesnikowski et al., 2016]] ; [[#Labbe--2017|Labbe et al., 2017]] ; [[#Sterle--2017|Sterle and Singletary, 2017]] ; [[#Hu--2018|Hu et al., 2018]] ; [[#Conevska--2019|Conevska et al., 2019]] ). Institutional adaptations are more frequently reported in cites than other sectors. Institutional adaptation may be particularly subject to reporting bias, however, with many institutional responses likely to be reported in the grey literature (see Chapter 17). Nature-based solutions are less frequently reported, except in Africa, where they are relatively well documented, and in the content of terrestrial systems where reports included species regeneration projects, wind breaks, erosion control, reforestation and riparian zone management ( [[#Munji--2014|Munji et al., 2014]] ; [[#Partey--2017|Partey et al., 2017]] ; [[#Muthee--2018|Muthee et al., 2018]] ).

'''''Some but not all adaptation-related responses are engaging vulnerable populations in planning or implementation''''' ( ''high confidence'' ) ( [[#Araos--2021|Araos et al., 2021]] ). Consideration of vulnerable populations is most frequently focused on low-income populations and women through the inclusion of informal or formal institutions or representatives in adaptation planning, or through targeted adaptations to reduce risk in these populations ( ''high confidence'' ). Consideration of vulnerable groups in adaptation responses is more frequently reported in the Global South ( ''medium confidence'' ). Engagement in adaptation planning of vulnerable elderly, migrants, and ethnic minorities remains low across all global regions ( ''medium confidence'' ). There is negligible literature on consideration of disabled peoples in planning and implementation of adaptation-related responses ( ''medium confidence'' ).

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==== 16.3.2.4 Adaptation Effectiveness, Adequacy and Risk Reduction ====

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Despite a lack of systematic methods for assessing general adaptation effectiveness, there is some evidence of risk reduction for particular places and hazards, especially flood and heat vulnerability. There is some evidence of a reduction in global vulnerability, particularly for flood risk ( [[#Jongman--2015|Jongman et al., 2015]] ; [[#Tanoue--2016|Tanoue et al., 2016]] ; [[#Miao--2019|Miao, 2019]] ) and extreme heat ( [[#Bobb--2014|Bobb et al., 2014]] ; [[#Boeckmann--2014|Boeckmann and Rohn, 2014]] ; [[#Gasparrini--2015|Gasparrini et al., 2015]] ; [[#Arbuthnott--2016|Arbuthnott et al., 2016]] ; [[#Chung--2017|Chung et al., 2017]] ; [[#Sheridan--2018|Sheridan and Allen, 2018]] ; [[#Folkerts--2020|Folkerts et al., 2020]] ). Investment in flood protection, including building design and monitoring and forecasting, have reduced flood-related mortality over time and are cost-effective (Bouwer and Jonkman 2018; Ward et al. 2017). Declining heat sensitivity, primarily reported in developed nations, has also been observed, and has been linked to air conditioning, reduced social vulnerability and improved population health ( [[#Boeckmann--2014|Boeckmann and Rohn, 2014]] ; [[#Chung--2017|Chung et al., 2017]] ; [[#Kinney--2018|Kinney, 2018]] ; [[#Sheridan--2018|Sheridan and Allen, 2018]] ). [[#Formetta--2019|Formetta and Feyen (2019)]] demonstrate declining global all-cause mortality and economic loss due to extreme weather events over the past four decades, with the greatest reductions in low-income countries, and with reductions correlated with wealth. Studies that correlate changes in mortality or economic losses with wealth indicators, to infer changes in vulnerability or exposure, lack direct empirical measures of vulnerability or exposure and are limited in their ability to assess how indirect effects of extreme events (e.g., morbidity, relocation, social disruption) may have changed or how changes may redistribute risk across populations.

There remain persistent difficulties in defining and measuring adaptation effectiveness and adequacy for many climate risks. No studies have systematically assessed the adequacy and effectiveness of adaptation at a global scale, across nations or sectors, or for different levels of warming. There has, however, been progress in operationalising assessment of adaptation feasibility (Cross-Chapter Box FEASIB in Chapter 18). Effectiveness of adaptation-related responses reflects whether a particular response actually reduces climate risk, typically through reductions in vulnerability and exposure (Figure 1.7 in [[IPCC:Wg2:Chapter:Chapter-1#1.4|Section 1.4]] ). Some adaptation-related responses may increase risk or create new risks (maladaptation) or have no or negligible impact on risk. Adequacy of adaptation-related responses refers to the extent to which responses are collectively sufficient to reduce the risks or impacts of climate change (Figure 1.7 in [[IPCC:Wg2:Chapter:Chapter-1#1.4|Section 1.4]] ). A set of adaptation-related responses may, for example, result in reduced climate risk (effectiveness), but these reductions may be insufficient to offset the level of risk and avoid loss and damages. Feasibility reflects the degree to which climate responses are possible or desirable, and integrates consideration of potential effectiveness. A feasibility assessment drawing on these methods is presented in Cross-Chapter Box FEASIB in Chapter 18.

Global adaptation is predominantly slow, siloed and incremental with little evidence of transformative adaptation ( ''high confidence'' ). In the absence of a general method to assess the adequacy of adaptation actions, we assessed evidence for transformational adaptation documented in peer-reviewed publications identified by a global stock-taking initiative ( [[#Berrang-Ford--2021b|Berrang-Ford et al., 2021b]] ) and in other AR6 chapters (2–15) (see Supplemental Material, SM16.1 for details). ‘Transformational adaptation’ refers to the degree to which adaptations have been implemented widely (scope), reflect major shifts (depth), occur rapidly (speed) and challenge limits to adaptation (limits, [[#Pelling--2015|Pelling et al., 2015]] ; [[#Few--2017|Few et al., 2017]] ; [[#Termeer--2017|Termeer et al., 2017]] , Table 16.1).

Based on the literature, the overall transformative nature of adaptation across most global regions and sectors is low ( ''high confidence)'' (Figure 16.6). Documented adaptations tend to involve minor modifications to usual practices taken to address extreme weather conditions ( ''high confidence'' ). For example, changing crop variety or timing of crop planting to address floods or droughts, new types of irrigation, pursuing supplementary livelihoods, and home elevations are widely reported but typically do not reflect radical or novel shifts in practice or values and are therefore considered low depth ( ''high confidence'' ) (see SM16.1 for more examples). Adaptations documented in the literature are also frequently focused on a single sector or small geographic area ( ''high confidence'' ). Actions taken by individuals or households are generally small in scope ( [[#Hintz--2018|Hintz et al., 2018]] ; [[#Hlahla--2018|Hlahla and Hill, 2018]] ) unless they are widely adopted (e.g., by farmers across a region) or address numerous aspects of life. National policies are more likely to be broad in scope ( [[#Puthucherril--2014|Puthucherril et al., 2014]] ), although they frequently focus on a single sector and are therefore still limited. The speed of adaptation is rarely noted explicitly, but the average speed documented in the literature is slow ( ''medium confidence'' ) (Cross-Chapter Box FEASIB in Chapter 18). Adaptation efforts frequently encounter either soft or hard limits (see [[#16.4|Section 16.4]] ), but there is ''limited evidence'' to suggest these limits are being challenged or overcome ( ''medium confidence'' ).

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[[File:4de6feb70ecd06157c4fd3613f5c1b54 IPCC_AR6_WGII_Figure_16_006.png]]

'''Figure 16.6 |''' '''Evidence of transformative adaptation by sector and region.''' Evidence of transformational adaptation does not imply effectiveness, equity or adequacy. Evidence of transformative adaptation is assessed based on the scope, speed, depth and ability to challenge limits of responses reported in the scientific literature (see Supplementary Material for methods). Studies relevant to multiple regions or sectors are included in assessment for each relevant sector/region.

Few documented responses are simultaneously widespread, rapid and novel ( ''high confidence'' ). Some examples exist, such as village relocations or creation of new multi-stakeholder resource governance systems ( [[#Schwan--2018|Schwan and Yu, 2018]] ; [[#McMichael--2020|McMichael and Katonivualiku, 2020]] ), but these are rare. In general, adaptations that are broad in scope tend to be slow ( ''medium confidence'' ), suggesting that achieving high transformation in all four categories (depth, scope, speed and limits) may be particularly challenging or even involve trade-offs.

'''Table 16.1 |''' Evidence of transformational adaptation assessed across four components (depth, scope, speed and limits). Transformational adaptation does not imply adequacy or effectiveness of adaptation (low transformation may be sufficient for some climate risks, and high transformation may be insufficient to offset others). Nevertheless, these components provide a systematic framework for tracking adaptation progress and assessing the state of adaptation-related responses. The ‘high’ categories across each component reflect more transformative scenarios. Methods are described in SM16.1.

{| class="wikitable"
|-
!
! colspan="3"| Transformative potential of adaptation

|-
| Dimensions

| '''Low'''

| '''Medium'''

| '''High'''

|-
| '''Overall'''

| ''Adaptation is largely sporadic and consists of small adjustments to Business-As-Usual. Coordination and mainstreaming are limited and fragmented.''

| ''Adaptation is expanding and increasingly coordinated, including wider implementation and multi-level coordination.''

| ''Adaptation is widespread and implemented at or very near its full potential across multiple dimensions.''

|-
| '''Depth'''

| Adaptations are largely expansions of existing practices, with minimal change in underlying values, assumptions or norms.

| Adaptations reflect a shift away from existing practices, norms or structures to some extent.

| Adaptations reflect entirely new practices involving deep structural reform, complete change in mindset, major shifts in perceptions or values, and changing institutional or behavioural norms.

|-
| '''Scope'''

| Adaptations are largely localised and fragmented, with ''limited evidence'' of coordination or mainstreaming across sectors, jurisdictions or levels of governance.

| Adaptations affect wider geographic areas, multiple areas and sectors, or are mainstreamed and coordinated across multiple dimensions.

| Adaptations are widespread and substantial, including most possible sectors, levels of governance, and actors.

|-
| '''Speed'''

| Adaptations are implemented slowly.

| Adaptations are implemented moderately quickly.

| Change is considered rapid for a given context.

|-
| '''Limits'''

| Adaptations may approach but do not exceed or substantively challenge soft limits.

| Adaptations may overcome some soft limits but do not challenge or approach hard limits.

| Adaptations exceed many soft limits and approach or challenge hard limits.

|}

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==== 16.3.2.5 Observed Maladaptation and Co-benefits ====

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'''There is increasing reporting of maladaptation globally (Table 16.2, [[IPCC:Wg2:Chapter:Chapter-17#17.5.1|Section 17.5.1]] ) (''' '''''high confidence''''' ''').''' Maladaptation has been particularly reported in the context of agricultural, forestry and fisheries practices, migration in the Global South, and some infrastructure-based interventions. Urban heat adaptations have been linked to maladaptation that increase health risks and/or energy consumption. Heat poses significant risks to the evolutionary tolerance levels of humans, animals and crops ( [[#Asseng--2021|Asseng et al., 2021]] ), and current adaptation interventions for reducing urban heat like cool or evaporation roofs and street trees may be insufficient to reduce heat-related vulnerabilities in some urban areas at higher levels of warming ( [[#Krayenhoff--2018|Krayenhoff et al., 2018]] ) (see also [[#16.4|Section 16.4]] on adaptation limits). There is evidence that autonomous adaptation by individuals and households can shift risk to others, with net increases in vulnerability. Intensification of pasture use as a coping response to climate-induced drought has been observed to increase risks to livestock reproduction and human life expectancy due to overgrazing, suggesting responses to pastoral vulnerability can cross tolerance limits for animals, humans and food available for foraging ( [[#Suvdantsetseg--2017|Suvdantsetseg et al., 2017]] ).

Evidence on ''realised'' co-benefits of implemented adaptation responses with other priorities in the SDGs is emerging among the areas of poverty reduction, food security, health and well-being, terrestrial and freshwater ecosystem services, sustainable cities and communities, energy security, work and economic growth, and mitigation (Table 16.2) ( ''high confidence'' ). Evidence on co-benefits of adaptation for mitigation is particularly strong, and is observed in various agricultural, forestry and land use management practices like agroforestry, climate-smart agriculture and afforestation ( [[#Kremen--2012|Kremen and Miles, 2012]] ; [[#Christen--2013|Christen and Dalgaard, 2013]] ; [[#Mbow--2014|Mbow et al., 2014]] ; [[#Locatelli--2015|Locatelli et al., 2015]] ; [[#Suckall--2015|Suckall et al., 2015]] ; [[#Wichelns--2016|Wichelns, 2016]] ; [[#Kongsager--2018|Kongsager, 2018]] ; [[#Debray--2019|Debray et al., 2019]] ; [[#Loboguerrero--2019|Loboguerrero et al., 2019]] ; [[#Morecroft--2019|Morecroft et al., 2019]] ; [[#Chausson--2020|Chausson et al., 2020]] ) as well as in the urban built environment ( [[#Perrotti--2020|Perrotti and Stremke, 2020]] ; [[#Sharifi--2020|Sharifi, 2020]] ). Evidence on co-benefits of implemented responses for other SDG priority areas is less developed, however, in the areas of education, gender inequality and reduced inequalities, clean water and sanitation, industry, innovation and infrastructure, consumption and production, marine and coastal ecosystem protection, and peace, justice, and strong institutions. This indicates a gap between some assumed likely co-benefits of adaptation and empirical evidence on the realisation of these co-benefits within the context of implemented adaptation responses ( [[#Berga--2016|Berga, 2016]] ; [[#Froehlich--2018|Froehlich et al., 2018]] ; [[#Gattuso--2018|Gattuso et al., 2018]] ; [[#Morris--2018|Morris et al., 2018]] ; [[#Chausson--2020|Chausson et al., 2020]] ; [[#Karlsson--2020|Karlsson et al., 2020]] ; [[#Krauss--2020|Krauss and Osland, 2020]] ).

'''Table 16.2 |''' Observed examples of maladaptation and co-benefits from adaptation-related responses in human systems.

{| class="wikitable"
|-
! Implemented adaptations

! Observed maladaptation

! References

|-
| colspan="3"| Agricultural and forestry practices

|-
| Intensified cultivation of marginal lands: clearing of virgin forests for farmland; frequent weeding; poorly managed irrigation schemes; dependence on rainfed agriculture

| Increased competition for resources such as water and nutrients; reduced soil fertility; invasive species; degraded environment; increased greenhouse gas emissions; reduced crops diversity and reduced harvest, thus increasing food insecurity in rural areas; accelerated illegal logging practices; increased vulnerability of herders, translated into poor health and working conditions (Mongolia)

| Bele et al. (2014); D’haen et al. (2014); [[#Chapman--2016|Chapman et al. (2016)]] ; [[#Ifeanyi-obi--2017|Ifeanyi-obi et al. (2017)]] ; [[#Suvdantsetseg--2017|Suvdantsetseg et al. (2017)]] ; [[#Villamayor-Tomas--2017|Villamayor-Tomas and Garcia-Lopez (2017)]] ; Afriyie et al. (2018); [[#Ticehurst--2018|Ticehurst and Curtis (2018)]] ; [[#Tran--2018|Tran et al. (2018)]] ; [[#Neset--2019|Neset et al. (2019)]] ; [[#Work--2019|Work et al. (2019)]] ; Yamba et al. (2019); [[#Singh--2020|Singh and Basu (2020)]]

|-
| Agroforestry systems

| Higher water demand where trees were combined with crops and livestock; native trees replaced with non-indigenous trees; reduced resilience of certain plants (e.g., cocoa); degraded soil and water quality and accelerated environmental degradation in Africa and Asia (Pakistan, Nepal, India, China, Philippines)

| [[#Nordhagen--2013|Nordhagen and Pascual (2013)]] ; D’haen et al. (2014); [[#Hoang--2014|Hoang et al. (2014)]] ; [[#Ruiz-Mallen--2015|Ruiz-Mallen et al. (2015)]] ; [[#Kibet--2016|Kibet et al. (2016)]] ; Chengappa et al. (2017); [[#Haji--2017|Haji and Legesse (2017)]] ; [[#Abdulai--2018|Abdulai et al. (2018)]] ; [[#Antwi-Agyei--2018|Antwi-Agyei et al. (2018)]] ; [[#Mersha--2018|Mersha and van Laerhoven (2018)]] ; [[#Ullah--2018|Ullah et al. (2018)]] ; [[#Krishnamurthy--2019|Krishnamurthy et al. (2019)]]

|-
| Agricultural transitions: commercialisation of common property; market integration and sedentarisation of pastoralists; adoption and expansion of commercial crops

| Soil degradation and high dependency on external inputs in South and Central America (El Salvador, Guatemala, Honduras, Nicaragua and Peru); dependency on foreign corporation seed systems; land enclosures; adaptation that forced local farmers in Costa Rica to switch crops to commercially viable products (e.g., from rice to sugar cane) impoverished the land by removing nutrients and affecting food security for smallholder farmers

| [[#Nordhagen--2013|Nordhagen and Pascual (2013)]] ; D’haen et al. (2014); [[#Warner--2015|Warner et al. (2015)]] ; [[#Kibet--2016|Kibet et al. (2016)]] ; ( [[#Warner--2016|Warner and Kuzdas, 2016]] ); [[#Haji--2017|Haji and Legesse (2017)]] ; [[#Antwi-Agyei--2018|Antwi-Agyei et al. (2018)]] ; [[#Mersha--2018|Mersha and van Laerhoven (2018)]] ; [[#Krishnamurthy--2019|Krishnamurthy et al. (2019)]] ; [[#Neset--2019|Neset et al. (2019)]]

|-
| Proper, improper and increased use of agrochemicals, pesticides and fertilizers

| Fertilizer and agrochemicals negatively affected soil quality and accelerated environmental degradation in several parts of Africa (Ghana, Nigeria) and Asia (Pakistan, Nepal, India, China, Philippines). In Europe (Sweden and Finland), there are concerns about the risk of pests and weeds developing immunity to pesticides, and drainage systems and rain transferred chemicals to other fields, thereby affecting arable land. In South and Central America (El Salvador, Guatemala, Honduras, Nicaragua and Peru), agrochemicals led to soil degradation, and high dependency on external input was reported. Loss of soil nutrients, increased GHG emissions (Sweden, Finland); high nitrate and phosphate concentration (Great Britain)

| [[#Postigo--2014|Postigo (2014)]] ; [[#Rodriguez-Solorzano--2014|Rodriguez-Solorzano (2014)]] ; [[#Fezzi--2015|Fezzi et al. (2015)]] ; [[#Sujakhu--2016|Sujakhu et al. (2016)]] ; [[#Begum--2017|Begum and Mahanta (2017)]] ; [[#de%20Sousa--2018|de Sousa et al. (2018)]] ; [[#Tang--2018|Tang et al. (2018)]] ; Yamba et al. (2019)

|-
| Tree planting

| The lack of shaded trees increased vulnerability to landslides in areas where Robusta coffee was grown (Mexico); new tree species to cope with climate change increased sensitivity and displaced non-indigenous trees (India; Tanzania and Kenya); cocoa planted under shade trees had higher mortality rate and more stress (Ghana); eucalyptus trees planted to reduce soil erosion had high water demand (Pakistan); in certain urban areas, trees planted to provide shade damaged buildings during heavy storms

| [[#Benito-Garzon--2013|Benito-Garzon et al. (2013)]] ; [[#Hoang--2014|Hoang et al. (2014)]] ; [[#Ruiz%20Meza--2015|Ruiz Meza (2015)]] ; Chengappa et al. (2017); [[#Abdulai--2018|Abdulai et al. (2018)]] ; [[#Ullah--2018|Ullah et al. (2018)]]

|-
| colspan="3"| Fisheries and water management

|-
| Increased fishing activity

| Fishery depletion and exacerbated negative trends in the ecosystem that threatened fishermen’s subsistence

| [[#Goulden--2013|Goulden et al. (2013)]] ; Mazur et al. (2013); [[#Rodriguez-Solorzano--2014|Rodriguez-Solorzano (2014)]] ; [[#Pershing--2016|Pershing et al. (2016)]] ; Kanda et al. (2017); [[#Kihila--2018|Kihila (2018)]] ; [[#Pinsky--2018|Pinsky et al. (2018)]]

|-
| Shrimp farming

| A driver of deforestation of mangroves in Bangladesh; imposes external cost on paddy farmers; salinity levels are relatively higher in paddy plots closer to shrimp ponds; coral mining increased vulnerability to flooding (in small islands in the Philippines)

| [[#Johnson--2016|Johnson et al. (2016)]] ; [[#Jamero--2017|Jamero et al. (2017)]] ; [[#Paprocki--2018|Paprocki and Huq (2018)]] ; [[#Sovacool--2018|Sovacool (2018)]] ; [[#Morshed--2020|Morshed et al. (2020)]]

|-
| Water irrigation infrastructure for agriculture; water desalination in response to water shortages

| Increased land loss; redistributed risk among agrarian stakeholders; affected the rural poor (Cambodia; Costa Rica); uneven distribution of cost and benefits (USA–Mexico border); desalination plants to led disproportionately high cost for low-income water users

| [[#Barnett--2013|Barnett and O’Neill (2013)]] ; [[#Olmstead--2014|Olmstead (2014)]] ; [[#Warner--2016|Warner and Kuzdas (2016)]] ; [[#Work--2019|Work et al. (2019)]]

|-
| Storage of large quantities of water in the home

| Water rendered unsafe for drinking due contamination by faecal coliforms in Zimbabwe; drought-induced changes in water harvesting and storage increased breeding sites for mosquitoes (Australia); water storage facilities and tanks provided ideal breeding conditions for mosquitoes and flies, bringing both vectors and diseases closer to people (Ethiopia)

| [[#Boelee--2013|Boelee et al. (2013)]] ; [[#Trewin--2013|Trewin et al. (2013)]] ; Kanda et al. (2017)

|-
| Increased number of farm dams for water storage; groundwater extraction and interbasin water transfers

| Reduced river and ground water flow downstream; water grabs from shared surface or groundwater resources with poorly defined property rights shifted vulnerability to other groups and ecosystems (Cambodia; California): water extractions increased risks for the environment and food security, while transfers reduced hydropower generation and resulted in higher costs paid by electricity consumers and health impacts from air pollution caused by more electricity generation from natural gas (California); increase the concentration in the hands of the more powerful large farmers (Argentina)

| Mazur et al. (2013); Christian-Smith et al. (2015); ( [[#Hurlbert--2016|Hurlbert and Mussetta, 2016]] ); Work et al.)

|-
| colspan="3"| Built environment

|-
| Seawalls and infrastructural development along coastlines

| Coastal erosion, beach losses, changes in water current, and destruction of natural ecosystems in Asia, Australasia, Europe and North America; increased or shifted erosion from protected to unprotected areas in Fiji, Marshall Islands, Nuie, Kiribati and Norway; failed or sped up flood waters and worsened conditions for riparian habitat and downstream residents; harmed nearby reefs and impeded autonomous adaptation practise that could be effective (Bangladesh)

| [[#Macintosh--2013|Macintosh (2013)]] ; [[#Maldonado--2014|Maldonado et al. (2014)]] ; [[#Porio--2014|Porio (2014)]] ; [[#Betzold--2015|Betzold (2015)]] ; [[#Renaud--2015|Renaud et al. (2015)]] ; Gundersen et al. (2016); Sayers et al. (2018); [[#Craig--2019|Craig (2019)]] ; [[#Javeline--2019|Javeline and Kijewski-Correa (2019)]] ; [[#Loughran--2019|Loughran and Elliott (2019)]] ; [[#Rahman--2019|Rahman and Hickey (2019)]] ; [[#Piggott-McKellar--2020|Piggott-McKellar et al. (2020)]] ; Simon et al. (2020) [[#Dahl--2017|Dahl et al. (2017)]]

|-
| Smart or green luxury real estate development designed to reduce impacts from storm surges and erosion along coastal area; artificial islands

| Redistributed risk and vulnerability; displaced and diminished adaptive capacity of vulnerable groups, created new population of landless peasants; negatively affected neighbouring coastal areas and local ecology (Lagos, Miami, Hanoi, Jakarta, Manila; Maldives)

| Caprotti et al. (2015); [[#Magnan--2016|Magnan et al. (2016)]] ; [[#Atteridge--2018|Atteridge and Remling (2018)]] ; [[#Ajibade--2019|Ajibade (2019)]] ; Salim et al. (2019); [[#Thomas--2019|Thomas and Warner (2019)]]

|-
| Subsidised insurance premiums for properties located in flood-prone areas, levees, dykes

| Rebuilding in risky areas

| [[#Shearer--2014|Shearer et al. (2014)]] ; O’Hare et al. (2016); [[#Craig--2019|Craig (2019)]] ; [[#Loughran--2019|Loughran and Elliott (2019)]]

|-
| Autonomous flood strategies such as sandbags, digging channels and sand walls around homes

| Sandbags used to reduce coastal erosion released plastics into the sea and led to loss of recreational value of beaches; sand walls shifted the flood impacts across space and time and were more detrimental to poor informal urban settlers (Dakar); caused erosion and degraded coastal lands (South Africa)

| [[#Schaer--2015|Schaer (2015)]] ; [[#Wamsler--2015|Wamsler and Brink (2015)]] ; ( [[#Chapman--2016|Chapman et al., 2016]] ); [[#Magnan--2016|Magnan et al. (2016)]] ; [[#Mycoo--2018|Mycoo (2018)]] ; [[#Rahman--2019|Rahman and Hickey (2019)]]

|-
| Top-down technocratic adaptation with no consideration for ecosystem biodiversity, local adaptive capacity and gender issues

| Ignored the complexities of the landscapes and socio-ecological systems; constrained autonomous adaptation due to time and labour demands of public work; increased gender vulnerability; hamper women’s water rights (South Africa); altered local gender norms (Ethiopia); led to a mismatch that undermine local-level processes that are vital to local adaptive capacity (Rwanda)

| [[#Cartwright--2013|Cartwright et al. (2013)]] ; [[#Goulden--2013|Goulden et al. (2013)]] ; [[#Nordhagen--2013|Nordhagen and Pascual (2013)]] ; [[#Carr--2014|Carr and Thompson (2014)]] ; [[#Nyamadzawo--2015|Nyamadzawo et al. (2015)]] ; [[#Ruiz-Mallen--2015|Ruiz-Mallen et al. (2015)]] ; [[#Djoudi--2016|Djoudi et al. (2016)]] ; Gautier et al. (2016); Gundersen et al. (2016); [[#Barnett--2018|Barnett and McMichael (2018)]] ; [[#Kihila--2018|Kihila (2018)]] ; [[#Mersha--2018|Mersha and van Laerhoven (2018)]] ; [[#Clay--2019|Clay and King (2019)]] ; [[#Currenti--2019|Currenti et al. (2019)]] ; [[#Yang--2019|Yang et al. (2019)]]

|-
| colspan="3"| Migration and relocation

|-
| Out-migration or rural-to-urban migration in response to food insecurity and agricultural livelihood depreciation

| Migration mostly undertaken by poorer households weakened local subsistence production capacity; disrupted family structures; reduced labour available for agricultural work; increased burden of responsibilities on women; fostered loss of solidarity within communities; increased divorce rates; exacerbated conflicts among different groups; increased pressure on urban housing and social services; expanded slum settlements around riparian and coastal areas including flood plains and swamplands (Ethiopia, Namibia, Benin, Botswana, Nigeria, Ghana, Kenya, Niger, Mail, Tanzania, Zimbabwe, South Africa, Morocco, Nepal, Pakistan, Bangladesh China, India, Australia, Nicaragua); out-migration from small communities had devastating consequences on their fragile economies, thereby reducing community resilience in the long term (Australia)

| [[#Su--2017|Su et al. (2017)]] ; [[#Aziz--2015|Aziz and Sadok (2015)]] ; [[#Bhatta--2016|Bhatta and Aggarwal (2016)]] ; [[#Clay--2019|Clay and King (2019)]] ; Elagib et al. (2017); [[#Gao--2018|Gao and Mills (2018)]] ; Kattumuri et al. (2017); [[#Magnan--2016|Magnan et al. (2016)]] ; [[#Ofoegbu--2016|Ofoegbu et al. (2016)]] ; Rademacher-Schulz et al. (2014);Rademacher-Schulz et al. (2014);Wiederkehr et al. (2018); Yegbemey et al. (2017); [[#Yila--2013|Yila and Resurreccion (2013)]] ; Nizami et al. (2019); [[#Mersha--2016|Mersha and Van Laerhoven (2016)]] ; [[#Ojha--2014|Ojha et al. (2014)]] ; [[#Radel--2018|Radel et al. (2018)]] ; [[#Gioli--2014|Gioli et al. (2014)]] ; [[#Hooli--2016|Hooli (2016)]] ; [[#Koubi--2016|Koubi et al. (2016)]]

|-
| Certain autonomous, forced and planned relocation

Temporary resettlement (India)

| Expansion of informal settlements in cities (Solomon Islands); relocation to areas prone to landslide and soil erosion or insufficient housing (Fiji); disproportionate burden on vulnerable communities (China); temporary relocation created gender inequality associated with minimal privacy; poor access to private toilets; sexual harassment; reduced sleep; insufficient or food rationing; exploitation and abuse of children (India); inadequate funding and governance mechanism for community-based relocation caused loss of culture, economic decline and health concerns (Alaska); relocation of supply chain to reduce exposure to climate change resulted in adverse outcomes for communities along the supply chain

| [[#Monnereau--2013|Monnereau and Abraham (2013)]] ; [[#Maldonado--2014|Maldonado et al. (2014)]] ; [[#Pritchard--2014|Pritchard and Thielemans (2014)]] ; [[#Averchenkova--2016|Averchenkova et al. (2016)]] ; [[#Lei--2017|Lei et al. (2017)]] ; [[#Barnett--2018|Barnett and McMichael (2018)]] ; [[#Currenti--2019|Currenti et al. (2019)]]

|-
| colspan="3"| Agricultural practices

|-
| Integrated agricultural practices (e.g., climate-smart agriculture, urban and peri-urban agriculture and forestry; agro-ecology; silvopasture; soil desalinisation; drainage improvement; integrated soil–crop system management; no tillage farming; rainwater harvesting; check dams)

| Mitigation, especially carbon sequestration (but see [[#Sommer--2018|Sommer et al., 2018]] ); improved household equity regarding farming decisions, particularly inclusion of women; food security

| [[#Furman--2014|Furman et al. (2014)]] ; [[#Lwasa--2014|Lwasa et al. (2014)]] ; [[#Kibue--2015|Kibue et al. (2015)]] ; [[#Nyasimi--2017|Nyasimi et al. (2017)]] ; [[#Aryal--2018|Aryal et al. (2018)]] ; [[#Han--2018|Han et al. (2018)]] ; [[#Kakumanu--2018|Kakumanu et al. (2018)]] ; Sikka et al. (2018); [[#Debray--2019|Debray et al. (2019)]] ; [[#Kerr--2019|Kerr et al. (2019)]] ; ( [[#Teklewold--2019a|Teklewold et al., 2019a]] ); Teklewold et al. (2019b); [[#Wang--2020|Wang et al. (2020)]] [[#Sommer--2018|Sommer et al. (2018)]]

|-
| Improved irrigation systems

| Mitigation, especially avoided emissions; improved crop yields

| [[#Islam--2020|Islam et al. (2020)]]

|-
| Conservation agriculture (e.g., crop diversification; soil conservation; cover cropping)

| Mitigation, especially carbon sequestration; increased crop yields; food security; reduced heat and water stress; increased food security

| [[#Helling--2015|Helling et al. (2015)]] ; [[#Sapkota--2015|Sapkota et al. (2015)]] ; [[#Kimaro--2016|Kimaro et al. (2016)]] ; [[#Mainardi--2018|Mainardi (2018)]] ; Asmare et al. (2019); [[#Gonzalez-Sanchez--2019|Gonzalez-Sanchez et al. (2019)]]

|-
| Return to traditional farming practices

| Mitigation, especially carbon sequestration

| [[#Pienkowski--2019|Pienkowski and Zbaraszewski (2019)]]

|-
| Place-specific practices and innovations: animal cross-breeding; direct crop seeding; site-specific nutrient management; irrigation innovations; use of riparian buffer strips; use of green winter land; rice–rice system

| Mitigation, especially carbon sequestration; improved crop yields; food security

| [[#Sushant--2013|Sushant (2013)]] ; Balaji et al. (2015); [[#Helling--2015|Helling et al. (2015)]] ; [[#Jorgensen--2016|Jorgensen and Termansen (2016)]] ; [[#Sen--2017|Sen and Bond (2017)]] ; [[#Wilkes--2017|Wilkes et al. (2017)]] ; [[#Kakumanu--2018|Kakumanu et al. (2018)]] ; [[#Mainardi--2018|Mainardi (2018)]] ; Sikka et al. (2018) [[#Yadav--2020|Yadav et al. (2020)]]

|-
| colspan="3"| Land and water management

|-
| Agroforestry

| Mitigation, especially carbon sequestration; biodiversity and ecosystem conservation; improved food security; plant species diversification; diversification of household livelihoods; improved household incomes; improved access to forage material; energy access and reduced fuel wood gathering time and distance for women; soil and water conservation; aesthetic improvements in landscapes

| [[#Holler--2014|Holler (2014)]] ; Suckall et al. (2015); [[#Sharma--2016|Sharma et al. (2016)]] ; [[#Nyasimi--2017|Nyasimi et al. (2017)]] ; [[#Pandey--2017|Pandey et al. (2017)]] ; [[#Schembergue--2017|Schembergue et al. (2017)]] ; [[#Ticktin--2018|Ticktin et al. (2018)]] ; [[#Debray--2019|Debray et al. (2019)]] ; [[#Jezeer--2019|Jezeer et al. (2019)]] ; [[#Krishnamurthy--2019|Krishnamurthy et al. (2019)]] ; Nyantakyi-Frimpong et al. (2019); [[#Tschora--2020|Tschora and Cherubini (2020)]]

|-
| Afforestation and reforestation programs;

forest management practices (e.g., tree thinning)

| Mitigation, especially carbon sequestration; biodiversity and ecosystem conservation; new employment opportunities; diversification of household livelihoods; increased household incomes; improved access to fuel wood; harvesting opportunities from enclosures

| [[#Holler--2014|Holler (2014)]] ; [[#Etongo--2015|Etongo et al. (2015)]] ; [[#Diederichs--2016|Diederichs and Roberts (2016)]] ; [[#Acevedo-Osorio--2017|Acevedo-Osorio et al. (2017)]] ; [[#Nyasimi--2017|Nyasimi et al. (2017)]] ; [[#Krishnamurthy--2019|Krishnamurthy et al. (2019)]] ; [[#Rahman--2019|Rahman et al. (2019)]] [[#Wolde--2016|Wolde et al. (2016)]]

|-
| Ecosystem-based adaptations such as mangrove restoration and natural coastal defences

| Mitigation, especially carbon sequestration; habitat enhancement and protection for marine species; prevention of floor-related deaths, injuries and damage; improved nutrition and income generation for local communities, improved water quality

| [[#Fedele--2018|Fedele et al. (2018)]]

[[#Roberts--2012|Roberts et al. (2012)]] ; [[#Morris--2019|Morris et al. (2019)]] ; ( [[#Jones--2020|Jones et al., 2020]] )

|-
| Sustainable water management

| Mitigation, especially avoided emissions; reduced water demand; increased awareness about impacts of water consumption; decreased incidence of faecal–oral disease transmission; decreased use of drinking water for irrigation; reduced soil loss; increased groundwater retention; increased vegetation cover; increased food security and health and well-being; increased forage for livestock and amount of cultivated area; enhanced recreational areas

| [[#Spencer--2017|Spencer et al. (2017)]] ; Siraw et al. (2018); [[#Stanczuk-Galwiaczek--2018|Stanczuk-Galwiaczek et al. (2018)]]

|-
| Return to traditional land management practices (e.g., the Ngitili system)

| Mitigation, especially carbon sequestration; increased water availability for household and livestock use; increase in presence of edible and medicinal plants; regional economic growth; reduced land management conflicts; increased household income and access to education for children; improved access to wood fuel and reduced collection time for women; improved wildlife habitat

| Duguma et al. (2014)

|-
| REDD+ participation to maintain intact forest ecosystems

| Mitigation, especially carbon sequestration; improved air quality; water and soil conservation; slowed rate of vector-borne disease; improved mental well-being associated with cultural continuity; clean water; nutritional and spiritual value of forest-derived foods; protection from violence related to natural resource extraction

| [[#McElwee--2017|McElwee et al. (2017)]] ; [[#Spencer--2017|Spencer et al. (2017)]]

|-
| colspan="3"| Urban planning and design

|-
| Spatial planning—walkable neighbourhood design; strategic densification

| Mitigation, particularly avoided emissions; public health—increases in physical activity, reductions in air pollution and urban heat island effect

| Beiler et al. (2016); [[#Belanger--2016|Belanger et al. (2016)]]

|-
| Urban greening (e.g., tree planting; construction of stormwater retention areas; construction of green roofs and cool roofs; provision of rainwater barrels; pervious pavement materials)

| Mitigation, particularly avoided emissions; public health improvements—increases in physical activity, reductions in air and noise pollution, reduced urban heat island effect, improved mental health; urban flood risk management; water savings; energy savings

| [[#Samora-Arvela--2017|Samora-Arvela et al. (2017)]] ; [[#Vahmani--2017|Vahmani and Jones (2017)]] ; Newell et al. (2018); [[#Alves--2019|Alves et al. (2019)]] ; [[#De%20la%20Sota--2019|De la Sota et al. (2019)]]

|-
| Improved building efficiency standards

| Mitigation, particularly avoided emissions; improved air quality; reduced urban heat island; improved natural indoor lighting

| Barbosa et al. (2015); [[#Koski--2016|Koski and Siulagi (2016)]] ; [[#Balaban--2017|Balaban and Puppim de Oliveira (2017)]] ; Landauer et al. (2019)

|-
| Use of local building materials

| Mitigation, particularly avoided emissions

| [[#Lundgren-Kownacki--2018|Lundgren-Kownacki et al. (2018)]]

|}

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