Editing IPCC:AR6/WGII/Chapter-18 (section)

=== 18.3.1 System Transitions as a Foundation for Climate Resilient Development ===

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In the AR6, system transitions are defined as ‘ ''the process of changing (the system in focus) from one state or condition to another in a given period of time'' ’ ( [[#IPCC--2018a|IPCC, 2018a]] ; [[#IPCC--2019b|IPCC, 2019b]] ). In the climate change solution space, system transitions represent an important mechanism for linking and enabling mitigation, adaptation and sustainable development options and actions ( ''very high confidence'' ). SR1.5C identified the need for rapid and far-reaching transitions in four systems—energy, land and terrestrial ecosystems, urban and infrastructure, and industrial systems ( [[#IPCC--2018b|IPCC, 2018b]] ; [[#IPCC--2018a|IPCC, 2018a]] ) (Sections 1.5.1 and 18.1). The SRCCL expanded on this with a focus on terrestrial systems, while SROCC added additional evidence from ocean and cryosphere systems. This section assesses the four system transitions discussed in the SR1.5C assessment in the context of CRD, while also extending the assessment to consider societal transitions as a cross-cutting, fifth transition important for CRD. Literature to support this assessment is also drawn from AR6 regional and sectoral chapters, which is synthesised later in this chapter ( [[#18.5|Section 18.5]] ).

As discussed in Box 18.3 ( [[#Hölscher--2018|Hölscher et al., 2018]] ), system transitions are linked to system transformation, which is defined as ‘ ''a change in the fundamental attributes of a system including altered goals or values'' ’ (Figure 18.1) ( [[#IPCC--2018a|IPCC, 2018a]] ). In a systems context, transitions focus on ‘complex adaptive systems; social, institutional and technological change in societal sub-systems’, while transformations are ‘ ''large scale societal change processes … involving social-ecological interactions'' ’ ( [[#IPCC--2018a|IPCC, 2018a]] ) (Box 18.1). Although system transitions are often identified in the literature as being necessary processes for large-scale transformations ( [[#Roggema--2012|Roggema et al., 2012]] ; [[#Hölscher--2018|Hölscher et al., 2018]] ), thereby making them a core enabler of CRD, they are not necessarily transformative in themselves.

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==== 18.3.1.1 Energy Systems ====

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Recent observed changes in global energy systems include continued growth in energy demand, led by increased demand for electricity by industry and buildings ( ''very high confidence'' )(Dhakal et al., 2022) . Growth in energy demand has also been driven by increased demand for industrial products, materials, building energy services, floor space and all modes of transportation. This growth in demand, however, has been moderated by improvements in energy efficiency in industry, buildings and transportation sectors ( ''very high confidence'' ) (Dhakal et al., 2022). There is also a trend of moving away from coal towards cleaner fuels, owing to lower natural gas prices and lower cost renewable technologies, and structural changes away from more energy-intensive industry.

Features of sustainable development, such as enhanced energy access, energy security, reductions in air pollution and economic growth, continue to be the dominant influence on the evolution of energy systems and decision making regarding energy investments and portfolios ( ''very high confidence'' ) (Clarke et al., 2022) . To date, climate policy has been comparatively less influential in driving energy transitions globally. Yet there are examples at the local, regional and national level of policy incentivising rapid changes in energy systems ( ''very high confidence'' ) (Clarke et al., 2022) . Many sustainable development priorities have co-benefits in terms of climate mitigation, such as air pollution and conservation policies reducing short-lived climate forcers and sequestering carbon respectively, as well adaptation benefits, such as improved energy access and environmental quality enhancing adaptive capacity ( ''very high confidence'' ) (Clarke et al., 2022) ( [[#de%20Coninck--2018|de Coninck et al., 2018]] ). Alternatively, sustainable development projects can have negative climate implications with, for instance, hydroelectric projects shut down by droughts or floods resulting in greater use of bunker and fuel oil, as well as natural gas.

In addition to sustainable development priorities driving change in energy systems, observed energy system trends have implications for sustainable development (e.g., [[#IEA--2019|IEA et al., 2019]] ). Observed changes in energy system size, rate of growth, composition and operations impact energy access, equity, environmental quality and well-being, with both synergies and trade-offs, including recent improvements in global access to affordable, reliable and modern energy services. For instance, in some countries, such as the USA, there has been a significant shift away from coal as a fuel source for electricity generation in favour of natural gas. More recently, however, renewables have emerged as the dominant form of new electricity generation ( [[#Gielen--2019|Gielen et al., 2019]] ). Similarly, for energy access in developing countries, renewable energy or hybrid distributed generation systems are increasingly being prioritised because of challenges associated with access, costs and environmental impacts from traditional fossil fuel-based energy technologies ( [[#Mulugetta--2019|Mulugetta et al., 2019]] ).

Energy systems have been a historical driver of climate change, but are also adversely affected by climate change impacts, including short-term shocks and stressors from extreme weather as well as long-term shifts in climatic conditions ( ''very high confidence'' ). The potential for such factors is often incorporated into local system designs, operations and response strategies. There have been changes in observed weather and extreme event hazards for the energy system, but to date, many are not attributable solely to anthropogenic climate change (USGCRP, 2017; [[#IPCC--2021a|IPCC, 2021a]] ). Nevertheless, with observed extremes shifting outside of what has been observed historically, existing design criteria and operations may not be optimal for future climate conditions and contingencies (Chapters 2 to 16). Overall, there is limited historical evidence on the efficacy of adaptation responses in reducing vulnerability of energy systems ( ''high agreement'' , ''limited evidence'' ). However, sustainable development trends, such as improving incomes, reducing poverty, and improving health and education have reduced vulnerability (Chapter 16), and improvements in system resiliency to extreme weather events and more efficient water management have occurred that have synergies with adaptation and sustainable development in general.

Available literature indicates that greenhouse gas emissions reductions have been achieved in response to climate actions including financial incentives to promote renewable energy, carbon taxes and emissions trading, removal of fossil fuel subsidies, and promotion of energy efficiency standards ( ''very high confidence'' ) (Clarke et al., 2022). Such policies tend to lead to a lower carbon intensity of GDP, due to structural changes in the use of energy and the adoption of new energy technologies. However, other drivers of change are also present and thus ongoing energy transitions and their future evolution are a response to both climatic and non-climatic considerations, with broader sustainable development priorities being a significant driver of change {Clarke, 2022 #4316.}

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==== 18.3.1.2 Urban and Infrastructure Systems ====

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Urban areas and their associated infrastructure are critical targets for CRD processes. This is a function of urban areas being the dominant settlement pattern, with over 55% of the global population living in cities ( [[#World%20Bank--2021|World Bank, 2021]] ). As a consequence, urban areas are also the focal point for energy use, land use change and consumption of natural resources, thereby making them responsible for an estimated 70% of global CO 2 emissions ( [[#Johansson--2012|Johansson et al., 2012]] ; [[#Ribeiro--2019|Ribeiro et al., 2019]] ). The trend towards increasing urbanisation is anticipated to create both challenges and opportunities for sustainable development, as well as climate action ( [[#Güneralp--2017|Güneralp et al., 2017]] ; [[#Li--2019a|Li et al., 2019a]] ).

The built environment is increasingly exposed to climate stresses and more frequent co-occurrences of climate shocks than in the past. This has the potential to increase rates of building and infrastructure degradation and increase damage from extreme weather events. The existing adaptation gaps and everyday risks within many cities, particularly those of the Global South, combined with escalating risk from climate change, makes rapid progress in enhancing urban resilience a high priority for CRD ( [[#Pelling--2018|Pelling et al., 2018]] ; [[#Davidson--2019|Davidson et al., 2019]] ; [[#Lenzholzer--2020|Lenzholzer et al., 2020]] ). Strategic investments in disaster risk reduction, including climate-resilient green infrastructure, updated building codes and land use planning can provide significant long-term cost savings and social benefits. Moreover, evaluating the relative merits of ‘fail safe’ versus ‘safe to fail’ approaches to infrastructure planning can help to identify more design principles that are more robust to the uncertainties of climate change and urbanisation ( [[#Kim--2017a|Kim et al., 2017a]] ; [[#Kim--2019|Kim et al., 2019]] ).

Much of the literature on urban resilience and sustainability focuses on addressing discrete challenges for urban infrastructure subsystems. Climate change has the potential to enhance stress on lifeline infrastructure services such as the provision of electricity, water and wastewater, communications and transportation—subsystems which are often underdeveloped in many regions of the world ( [[#Arku--2021|Arku and Marais, 2021]] ; [[#Sitas--2021|Sitas et al., 2021]] ). For example, a warming and more variable climate can increase stress on electricity grids by reducing transmission efficiency, increasing cooling demand requirements, and by increasing exposure to climate shocks such as heatwaves, floods and storms ( [[#Bartos--2015|Bartos and Chester, 2015]] ; [[#Auffhammer--2017|Auffhammer et al., 2017]] ; [[#Perera--2020|Perera et al., 2020]] ). Accordingly, a significant focus on the energy transition is on achieving the dual goals of reducing the carbon footprint of energy while also increasing resilience of energy supply to current and future threats. For example, renewable energy generation and storage technologies that are modular and distributed and provide enhanced resilience to shocks and stresses from climate change (Venema and [[#Temmer--2017a|Temmer, 2017a]] ).

Similarly, building and maintaining urban water systems that are resilient to climate shocks requires significant changes in water demand, infrastructure and management. Enhancing redundancy in water supply and the flexibility to shift between surface and groundwater options aids adaptation. Decentralised water supply and sanitation options are now feasible and can provide greater resilience than most centralised systems ( [[#Parry--2017|Parry, 2017]] ), provided they have adequate supply ( [[#Leigh--2019|Leigh and Lee, 2019]] ; [[#Rabaey--2020|Rabaey et al., 2020]] ). Water conservation and green infrastructure options for stormwater management are proven approaches for reducing climate risks (Venema and [[#Temmer--2017b|Temmer, 2017b]] ), with adaptation and mitigation co-benefits. Water demand management and rainwater harvesting contribute to climate change mitigation and increase adaptive capacity by increasing resilience to climate change impacts such as drought and flooding ( [[#Paton--2014|Paton et al., 2014]] ; [[#Berry--2015|Berry et al., 2015]] ). In addition, they can contribute to restoring urban ecosystems that offer multiple ecosystem services to citizens ( [[#Berry--2015|Berry et al., 2015]] ) {Lwasa, 2022 #4317} . The context-appropriate development of green spaces, protecting ecosystem services and developing nature-based solutions, can increase the set of available urban adaptation options ( [[#IPCC--2018b|IPCC, 2018b]] ), while creating opportunities for more complex and dynamic approaches to urban water management ( [[#Franco-Torres--2020|Franco-Torres et al., 2020]] ). For example, the Netherlands’ ‘Room for the River’ policy focuses on not only achieving higher flood resilience, but also improving the quality of riverine areas for human and ecological well-being ( [[#Busscher--2019|Busscher et al., 2019]] ).

An overarching focus of urban sustainability is the reversal of long-standing trends of ecosystem fragmentation and degradation that have resulted in growing separation between human and natural systems within urban environments ( [[#IPBES--2019|IPBES, 2019]] ) (Lwasa et al., 2022). Urban ecosystems and the integration of nature-based solutions and green infrastructure into urban areas can yield benefits that facilitate achievement of the SDGs. There has been growing recognition of urban ecosystems as social, cultural and economic assets that can support economic development while also enhancing resilience to extreme weather events and improving air and water quality ( [[#Shaneyfelt--2017|Shaneyfelt et al., 2017]] ; [[#Matos--2019|Matos et al., 2019]] ). Investing in urban ecosystems and green infrastructure can provide lower-cost solutions to multiple urban development challenges when compared with traditional infrastructure systems ( [[#Terton--2017|Terton, 2017]] ). Relatedly, agriculture, while largely a rural system, is increasingly expanding within urban areas. Urban agriculture enables citizens to fulfil some of their food needs, improving urban resilience to food shortages, enhancing biodiversity and increasing coping capacity during disasters ( [[#Demuzere--2014|Demuzere et al., 2014]] ; [[#Clucas--2018|Clucas et al., 2018]] ) (Lwasa et al., 2022). Strengthening urban agroecosystems therefore increases resilience to supply shocks from climate change impacts and can contribute to community cohesion ( [[#Temmer--2017a|Temmer, 2017a]] ).

Overall, the discourse in the literature regarding the future of cities emphasises the importance of viewing cities as more than just their physical infrastructure that can be made more resilient through engineering solutions ( [[#Davidson--2019|Davidson et al., 2019]] ). Rather, urban areas are increasingly conceptualised as complex socio-ecological or socio-technical systems ( ''very high confidence'' ) ( [[#Patorniti--2017|Patorniti et al., 2017]] ; [[#Patorniti--2018|Patorniti et al., 2018]] ; [[#Visvizi--2018|Visvizi et al., 2018]] ; [[#Savaget--2019|Savaget et al., 2019]] ). Such frameworks integrate physical, cyber, social and ecological elements of cities in pursuit of resilience and sustainability transitions, and they recognise the role of governance and engagement processes as being central to system change ( [[#Temmer--2017b|Temmer, 2017b]] ). Nevertheless, some authors have cautioned that urban transitions will be associated with synergies as well as trade-offs with respect to sustainable development ( ''very high confidence'' ) ( [[#Maes--2019|Maes et al., 2019]] ; [[#Sharifi--2020|Sharifi, 2020]] ).

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==== 18.3.1.3 Land, Oceans and Ecosystems ====

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Land, oceans and terrestrial ecosystems are in transition globally, with anthropogenic factors including climate change being a major driving force ( ''very high confidence'' ) ( [[#IPBES--2019|IPBES, 2019]] ) (Box 6). Seventy-five percent of the land surface has been significantly altered, 66% of the ocean area is experiencing increasing cumulative impacts and over 85% of wetland areas have been lost ( [[#IPBES--2019|IPBES, 2019]] ). Since 1970, only four out of eighteen recognised ecosystem services assessed have improved in their functioning: agricultural production, fish harvest, bioenergy production and material harvests. The other 14 ecosystem services have declined ( [[#IPBES--2019|IPBES, 2019]] ), raising concerns about the capacity of ecosystems and their services to support sustainable and CRD.

Given the pressures on land, oceans and ecosystems, enhancing resilience to climate change and other pressures of human development is a core priority of transition in these systems. Yet there are a few recorded initiatives that provide evidence of successful improvement in ecosystem resilience ( ''high agreement'' , ''limited evidence'' ). Similarly, although there is significant evidence that a broad range of adaptation initiatives have been pursued across global regions and sectors, including a rapid expansion of nature- or ecosystem-based solutions ( [[#Mainali--2020|Mainali et al., 2020]] ), there is ''limited evidence'' of how these planned climate adaptation efforts have contributed to enhanced ecosystem resilience. Additional research is necessary to evaluate these efforts in terms of their performance and also to identify mechanisms for scaling them up in different contexts. As an example, Paik et al. ( [[#Paik--2020|Paik et al., 2020]] ) record the increased diffusion of salt tolerant rice varieties in the Mekong River Delta, which is at risk of sea level rise and an associated saline intrusion. This is a low-cost adaption to saline ingress, that increases food productivity and reduces the risk of outmigration for this vulnerable agricultural region.

Evidence of the interactions between ecosystems and resilience come from a range of sources including both regional and sectoral examples (Box 18.2; Tables 18.7–18.8. For example, regional examples suggest that the use of land to produce biofuels could increase the resilience of production systems and address mitigation needs (Box 2.2). Nevertheless, the potential of bioenergy with carbon capture and storage (BECCS) to induce maladaptation needs deeper analysis ( [[#Hoegh-Guldberg--2019|Hoegh-Guldberg et al., 2019]] ). Climate Smart Forestry (CSF) in Europe provides an example of the use of sustainable forest management to unlock the EU’s forest sector potential ( [[#Nabuurs--2017|Nabuurs et al., 2017]] ). This is in response to diverse climate impacts ranging from pressure on spruce stocks in Norway and the Baltics, on regional biodiversity in the Mediterranean region, and the opportunity to use afforestation and reforestation to store carbon in forests ( [[#Nabuurs--2019|Nabuurs et al., 2019]] ). CSF considers the full value chain from forest to wood products and energy and uses a wide range of measures to provide positive incentives to firmly integrate climate objectives into the forestry sector. CSF has three main objectives; (i) reducing and/or removing greenhouse gas emissions; (ii) adapting and building forest resilience to climate change; and (iii) sustainably increasing forest productivity and incomes ( [[#Verkerk--2020|Verkerk et al., 2020]] ).

Other solutions focus on specific subsectors. Mutually supportive climate and land policies have the potential to save resources, amplify social resilience, support ecological restoration, and foster engagement and collaboration between multiple stakeholders (IPCC, 2019 f, C.1). Land-based solutions can combat desertification in specific contexts: water harvesting and micro-irrigation, restoring degraded lands using drought-resilient ecologically appropriate plants, agroforestry and other agroecological and ecosystem-based adaptation practices (IPCC, 2019 f, B.4.1). Reducing dust, sandstorms and sand dune movement can lessen the negative effects of wind erosion and improve air quality and health. Depending on water availability and soil conditions, afforestation, tree planting and ecosystem restoration programmes using native and other climate-resilient tree species with low water needs, can reduce sand storms, avert wind erosion and contribute to carbon sinks, while improving micro-climates, soil nutrients and water retention (IPCC, 2019 f, B.4.2).

Coastal blue carbon ecosystems, such as mangroves, salt marshes and seagrasses, can help reduce the risks and impacts of climate change, with multiple co-benefits. Over 150 countries contain at least one of these coastal blue carbon ecosystems and over 70 contain all three. Successful implementation of measures of carbon storage in coastal ecosystems could assist several countries in achieving a balance between emissions and removal of greenhouse gases. Carbon storage in marine habitats can be up to 1,000 tC ha –1 , higher than most terrestrial ecosystems. Conservation of these habitats would also sustain a wide range of ecosystem services, assist with climate adaptation by improving critical habitats for biodiversity, enhance local fishery production and protect coastal communities from sea level rise (SLR) and storm events ( [[#IPCC--2019b|IPCC, 2019b]] ). Ecosystem-based adaptation is a cost-effective coastal protection tool that can have many co-benefits, including supporting livelihoods, contributing to carbon sequestration and the provision of a range of other valuable ecosystem services ( [[#IPCC--2019b|IPCC, 2019b]] ).

Diversification of food systems is another component of land, ocean and ecosystem transitions that are consistent with CRD. Balanced diets, featuring plant-based foods such as those based on coarse grains, legumes, fruits and vegetables, nuts and seeds, and animal-sourced food produced in a resilient, sustainable and low-greenhouse gas (GHG) emission manner, are major opportunities for adaptation and mitigation and improving human health. By 2050, dietary changes could free several million km 2 of land and provide a mitigation potential of 0.7–8.0 Gt CO 2 -eq yr -1 , relative to Business-As-Usual projections.

For coastal systems, many frameworks for climate resilience and adaptation have been developed since the AR5 ( [[#Hoegh-Guldberg--2014|Hoegh-Guldberg et al., 2014]] ; [[#Settele--2014|Settele et al., 2014]] ) with substantial variations in approach between and within countries and across development status. Few studies have assessed the success of implementing these frameworks owing to the time-lag between implementation, monitoring, evaluation and reporting ( [[#IPCC--2019g|IPCC, 2019g]] ). As an example, the Nature-Based Climate Solutions for Oceans initiative has the potential to restore, protect and manage coastal and marine ecosystems, adapt to climate change, improve coastal resilience, and enhance their ability to sequester and store carbon ( [[#Hoegh-Guldberg--2019|Hoegh-Guldberg et al., 2019]] ).

Polar regions will be profoundly different in the future. The degree and nature of that difference will depend strongly on the rate and magnitude of global climate change, which will influence adaptation responses regionally and worldwide. Future climate-induced changes in the polar oceans, sea ice, snow and permafrost will drive habitat and biome shifts, with associated changes in the ranges and abundance of ecologically important species ( [[#IPCC--2019g|IPCC, 2019g]] ). Innovative tools and practices in polar resource management and planning show strong potential in improving society’s capacity to respond to climate change. Networks of protected areas, participatory scenario analysis, decision support systems and community-based ecological monitoring that draws on local and Indigenous knowledge and self-assessments of community resilience contribute to strategic plans for sustaining biodiversity and limit risk to human livelihoods and well-being. Experimenting, assessing and continually refining practices while strengthening links with decision making has the potential to ready society for the expected and unexpected impacts of climate change ( [[#IPCC--2019g|IPCC, 2019g]] ).

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==== 18.3.1.4 Industrial Systems ====

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Industrial emissions have been growing faster since 2000 compared with emissions in any other sector, driven by increased extraction and production of basic materials ( [[#Crippa--2019|Crippa et al., 2019]] ; [[#IEA--2019|IEA, 2019]] ) ( ''very high confidence'' ). About one-third of the total emissions are contributed by the industry sector, if indirect emissions from energy use are considered ( [[#Crippa--2019|Crippa et al., 2019]] ). The COVID-19 pandemic has caused a significant decrease in demand for fuels, oil, coal, gas and nuclear energy ( [[#IEA--2020|IEA, 2020]] ). However, there is concern that the rebound in the crisis will reverse this trend ( [[#IEA--2020|IEA, 2020]] ). Accordingly, the literature suggests a combined set of measures is beneficial for facilitation a transition of industrial systems in support of CRD. This includes (i) dematerialisation and decarbonisation of industrial systems, (ii) establishment of supportive governance, policies and regulations, and (iii) implementation of enabling corporate strategies.

Decarbonisation and dematerialisation strategies have been proposed as key drivers for the transition of industrial systems (Fischedick et al., 2014; [[#Worrell--2016|Worrell et al., 2016]] ). The former involves limiting carbon emissions from industrial processes ( [[#IEA--2017|IEA, 2017]] ; [[#Hildingsson--2019|Hildingsson et al., 2019]] ), while the latter involves improving material efficiency, developing circular economies, raw material demand management, environmentally friendly product and process innovations, and environmentally friendly supply chain management ( [[#Worrell--2016|Worrell et al., 2016]] ; [[#Petrides--2018|Petrides et al., 2018]] ).

Recent modelling suggests that stocks of manufactured capital, including buildings, infrastructure, machinery and equipment, stabilise as countries develop and decouple from GDP ( ''high agreement'' , ''medium evidence'' ). For instance, [[#Bleischwitz--2018|Bleischwitz et al. (2018)]] confirmed the occurrence of a saturation effect for materials in four energy-intensive sectors (steel, cement, aluminum and copper) in five industrialised countries (Germany, Japan, the UK, the USA and China). High growth in the supply of materials may still drive global demand for new products in the coming years for developing countries that are still far from saturation levels. Therefore, accelerating industrial transitions to drive the decoupling of industrial emissions from economic growth and facilitate broader transformation in industrial systems can be one component of CRD.

Continued transitions in the industrial sector will be contingent on technological innovation. Although technologies exist to drive emissions in industrial sectors to very low or zero emissions, they require 5–15 years of innovation, commercialisation and intensive policies to ensure uptake ( [[#Åhman--2017|Åhman et al., 2017]] ) ( ''high agreement'' , ''medium evidence'' ). For instance, several options exist to reduce GHG emissions related to steel production process including increasing the share of the secondary route ( [[#Pauliuk--2013|Pauliuk et al., 2013]] ), hydrogen-based direct reduced iron ( [[#Vogl--2018|Vogl et al., 2018]] ), aqueous electrolysis rout ( [[#Cavaliere--2019|Cavaliere, 2019]] ) and plasma process ( [[#Quader--2016|Quader et al., 2016]] ).

Industrial transitions are also contingent upon consumer behaviour in terms of preferences for, and rates of, consumption of industrial products. Sustainable consumption can play an important role in sustainable production ( [[#Allwood--2013|Allwood et al., 2013]] ; [[#Allwood--2019|Allwood et al., 2019]] ). This suggests feedbacks between industrial production and consumption in driving industrial transitions. For example, sustainable consumption could be triggered and/or enabled through sustainable production processes that provide more sustainable options to consumers as well as public or private promotional campaigns that promote those options. Meanwhile, demand from consumers for more sustainable options could help to drive the expansion of markets and innovation among industrial producers to meet that demand. However, some have argued that such promotional campaigns that target consumers do little to incentivize sustainable development and climate action ( [[#Farrell--2015|Farrell, 2015]] ; [[#Grydehøj--2017|Grydehøj and Kelman, 2017]] ).

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==== 18.3.1.5 Societal Systems ====

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This chapter contributes a fifth system transition in addition to the four which have already been introduced by SR1.5: the societal systems transition. While society and people also feature in the other systems transitions, the purpose of defining a fifth transition is to explicitly highlight the challenges associated with changes in behaviour, attitudes, values and consciousness required to achieve CRD. One caveat of considering transitions in societal systems is the limit to which the nature of change is known: transitions accomplish reconfigurations towards a relatively known destination. Historical and current differences between and within nations translate to a multitude of equally valid but diverse priorities for development, for example the understanding of development towards progress as linear has been challenged as being a Western concept by scholars of colonialisation ( [[#Sultana--2019|Sultana et al., 2019]] ). Thus, societal transitions are understood as being intrinsically diverse for the purpose of achieving CRD.

The four systems transitions identified in SR1.5 already include a component of societal change—for example, attitude change is part of public acceptance that facilitates shifts in energy including changing electricity to renewables ( [[IPCC:Wg2:Chapter:Chapter-4|Chapter 4]] SR1.5, [[IPCC:Wg2:Chapter:Chapter-4#4.3.1|Section 4.3.1.1]] ) and developing nuclear power ( [[IPCC:Wg2:Chapter:Chapter-4#4.3.1|Section 4.3.1.3]] ), and behavioural change is a part of shifting irrigation practices to drive required land and ecosystems transitions ( [[IPCC:Wg2:Chapter:Chapter-4#4.3.2|Section 4.3.2.1]] ). Extracting societal transitions also allows for a detailed examination of other societal dimensions that facilitate systems transitions, for example justice issues relating to water and energy access and distribution, and land use. Societal transition, sometimes known as ‘societal transformation’, is an established concept in different literatures, as described below. Transformation and transition are terms often used as synonyms ( [[#Hölscher--2018|Hölscher et al., 2018]] ), although different schools of thought understand them as sub-components of each other, for example transition driving transformation, or transformation driving transition. For a more detailed discussion on the differences between transition and transformation represented in the literature, see Box 18.1.

Societal transitions for the purpose of this report are understood as the collection of shifts in attitudes, values, consciousness and behaviour required to move towards CRD. This builds on the SR1.5 ( [[#IPCC--2018a|IPCC, 2018a]] : 599) definition of societal (social) transformation: ‘A profound and often deliberate shift initiated by communities towards sustainability, facilitated by changes in individual and collective values and behaviours, and a fairer balance of political, cultural, and institutional power in society’. This includes accepting Indigenous knowledge and local knowledge (IKLK) as an equally valid form of knowledge as compared with Western, scientific knowledge (see Cross-Chapter Box INDIG) and recognition of the role of shifting gender norms to achieve climate resilience (see Cross-Chapter Box GENDER). Changes associated with societal transitions are not specific to defined systems (e.g., energy, industry, land/ecosystems or urban/infrastructure). Rather, these sectoral systems are embedded within broader societal systems, including for example political systems, economic systems, knowledge systems and cultural systems ( [[#Davelaar--2021|Davelaar, 2021]] ; [[#Turnhout--2021|Turnhout et al., 2021]] ; [[#Visseren-Hamakers--2021|Visseren-Hamakers et al., 2021]] ). Changes that happen in these broader social systems can therefore prompt changes in all systems embedded within them, meaning that societal transition is key to transforming across a range of sectors and topics ( [[#Leventon--2021|Leventon et al., 2021]] ). Furthermore, societal transition requires changes in individual behaviours, but also in the broader conditions that shape these behaviours. These broader conditions are largely related to questions of power, in enforcing dominant political economies and social-technological mindsets ( [[#Stoddard--2021|Stoddard et al., 2021]] ). This section also briefly describes the various trains of research on societal transitions and transformation.

Because of the multiple sectors, interests and scales that are involved in societal transitions, understanding and creating evidence on transitions requires shifting across system boundaries and finding ways to transcend disciplinary silos. Relevant research includes work within the topic of transformation and transitions ( [[#Hölscher--2018|Hölscher et al., 2018]] ). Transformations literature can be split into multiple sub-concepts and requires engagement with multiple schools of thought ( [[#Feola--2015|Feola, 2015]] ; [[#Feola--2021|Feola et al., 2021]] ). Much focus within transformations research is currently related to biodiversity conservation ( [[#Massarella--2021|Massarella et al., 2021]] ), and transitions work tends towards a focus in urban areas ( [[#Loorbach--2017|Loorbach et al., 2017]] ). Though there is also work in both that is more broadly labelled as sustainability transformations or transitions ( [[#Luederitz--2017|Luederitz et al., 2017]] ). Furthermore, there is likely to be much relevant literature that does not explicitly label itself as transformations or transitions ( [[#Feola--2021|Feola et al., 2021]] ). For example, we could look to political science theories on policy change ( [[#Leventon--2021|Leventon et al., 2021]] ) and historical perspectives on social change. Bridging these divides will require a deeper rethinking in the research community to undo power structures that marginalise diverse knowledge ( [[#Caniglia--2021|Caniglia et al., 2021]] ; [[#Lahsen--2021|Lahsen and Turnhout, 2021]] ).

There are a number of concepts proposed as pathways to creating societal transitions; usually centred around the idea of working with individuals and communities to change their mindsets as a way to change the way they manage their local environments or behave. Transformations work explores how values are pathways towards sustainability, for example by changing values, through making values explicit, through negotiation and by eliciting values ( [[#Horcea-Milcu--2019|Horcea-Milcu et al., 2019]] ). Human nature connections is a further concept that is identified as a way to shift values and behaviours across a range of disciplines ( [[#Ives--2017|Ives et al., 2017]] ). The role of learning and Indigenous knowledge is also explored ( [[#Lam--2020|Lam et al., 2020]] ). These three concepts have had particular salience in discussions around transformations for biodiversity conservation and restoration, related to the IPBES assessment on Values ( [[#Pascual--2017|Pascual et al., 2017]] ; [[#Peterson--2018|Peterson et al., 2018]] ). They largely focus on the need to engage with people’s values, connections and knowledge to better manage the social–ecological system they are in.

Focusing on bottom-up and community-led transformations, there is emphasis on the role of grassroots organisations in transformations. Community actions around specific locations or topics have parallels to the idea of transformative spaces. They are sites of innovative activity ( [[#Seyfang--2007|Seyfang and Smith, 2007]] ). Grassroots organisations can bridge the local and the political scales by politicising actors and creating new interactions between individuals and political processes ( [[#Novák--2021|Novák, 2021]] ). They are a collective approach to pushing for both individual and societal change ( [[#Sage--2021|Sage et al., 2021]] ).

Despite a current lack of empirical evidence, there are numerous frameworks emerging for exploring societal transitions across levels. There is focus on pathways for sustainability transitions, which tends to look at projected, normative scenarios for the future, and explore or back-cast the institutional and societal changes that are required to get there ( [[#Westley--2011|Westley et al., 2011]] ; [[#Sharpe--2016|Sharpe et al., 2016]] ). There is also work that looks at scaling up of smaller sustainability initiatives, through processes of scaling up, scaling out and scaling deep ( [[#Moore--2015|Moore et al., 2015]] ; [[#Lam--2020|Lam et al., 2020]] ). In particular, systems thinking provides an organising framework for bringing together multiple disciplines and perspectives, to understand problem framings, and normative and design aspects of social systems and behaviours ( [[#Foster-Fishman--2007|Foster-Fishman et al., 2007]] ). Within this, [[#Meadows--1999|Meadows (1999)]] framework of leverage points for systems transformation has been operationalised within the sustainability transformations debate ( [[#Abson--2017|Abson et al., 2017]] ). Here, system properties relating to system paradigms and design are leverage points where interventions can create greatest system change; shallower leverage points relate to materials and processes. This framework is increasingly being used across a range of sustainability problems as boundary objects for cross-disciplinary, critical research ( [[#Fischer--2019|Fischer and Riechers, 2019]] ; [[#Leventon--2021|Leventon et al., 2021]] ; [[#Riechers--2021|Riechers et al., 2021]] ).

Analyses of societal transitions have had limited engagement with adaptation questions. The focus of the sub-field of sustainability transitions on a few industrialised nations, mostly in North America and Europe, limited the field’s development to assumptions born from the experiences in those areas. More recent studies have sought to understand sustainability transitions in other countries, especially emerging economies ( [[#Wieczorek--2018|Wieczorek, 2018]] ; [[#Köhler--2019|Köhler et al., 2019]] ). In particular, China has received attention from scholars on sustainability transitions ( [[#Huang--2018|Huang et al., 2018]] ; [[#Lo--2019|Lo and Castán Broto, 2019]] ; [[#Castán%20Broto--2020|Castán Broto et al., 2020]] ; [[#Huang--2020|Huang and Sun, 2020]] ). As a result, some pressing issues related to societal transitions for adaptation have received limited attention compared with that paid to other system transitions. However, more recently, scholarship has begun examining transitions that have turned to nature and nature-based solutions. Adaptive transitions are an intermediary step towards sustainability transitions, whereby multiple actions at material and institutional levels are combined towards improving adaptation outcomes ( [[#Pant--2015|Pant et al., 2015]] ; [[#Scarano--2017|Scarano, 2017]] ).

<div id="box-18.5" class="h2-container box-container"></div>

'''Box 18.5 | The Role of Ecosystems in Climate Resilient Development'''
<div id="h2-26-siblings" class="h2-siblings"></div>

Ecosystems and their services closely relate to climate resilient development (CRD). Climate change has impacted ecosystems across a range of scales, and those impacts have been exacerbated by other ecological impacts associated with human activities. Ecosystem-based adaptation strategies have been developed and are crucial to CRD. However, knowledge and evidence still missing, and cultural services—in contrast to provision and regulation services as main benefits and supporting services as co-benefits—are less well addressed in the literature.

'''Ecosystems Play a Key Role in CRD'''
A key element of CRD is ensuring that actions taken to mitigate climate change do not compromise adaptation, biodiversity and human needs. Maintaining ecosystem health, linked to planetary health, is an integral part of the goals of CRD. The 2005 Millennium Ecosystem Assessment (MEA) defined ecosystem services as ‘ ''the benefits people obtain from ecosystems'' ’, and categorised the services in to provisioning, regulating, supporting and cultural services ( [[#Millennium%20Ecosystem%20Assessment--2005|Millennium Ecosystem Assessment, 2005]] ; [[#IPBES--2019|IPBES, 2019]] ). The 2019 Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) broadened the definition to ‘ ''the contributions, both positive and negative, of living nature to the quality of life for people'' ’, and developed a classification of 18 categories ( [[#IPBES--2019|IPBES, 2019]] ).

Table Box 18.5.1 demonstrates how ecosystem services connect to sustainable development goals (SDGs) and CRD. MEA’s provisioning service generally connects to the IPBES’ material services, mostly contributing to the SDG cluster associated with nature’s contribution to people (NCP) ( [[#Millennium%20Ecosystem%20Assessment--2005|Millennium Ecosystem Assessment, 2005]] ; [[#IPBES--2019|IPBES, 2019]] ) and to ‘ '''D''' evelopment’ in CRD. MEA’s regulating and supporting services connect to IPBES’ non-material services, contributing to SDG clusters of Nature and Driver of change in nature and NCP and to ‘ '''R''' esilience’ in CRD. MEA’s cultural services connect to IPBES’ non-material services, contributing to SDG clusters of good quality of lift (GQL) and to '''E''' nabling conditions for CRD.

'''Table Box 18.5.1 |''' Ecosystem services (based on the Millennium Ecosystem Assessment [MEA] and the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services [IPBES] classifications) and their connections to sustainable development goals (SDGs) and climate resilient development (CRD) ( [[#Millennium%20Ecosystem%20Assessment--2005|Millennium Ecosystem Assessment, 2005]] ; [[#IPBES--2019|IPBES, 2019]] ).

{| class="wikitable"
|-
! colspan="2"| '''Ecosystem services'''

! rowspan="2"| '''SDGs'''

! rowspan="2"| '''CRD'''

|-
! '''MEA'''

! '''IPBES'''

|-
| '''P''' rovisioning services

| 11 Energy

12 Food and feed

13 Materials and assistance

14 Medicinal, biochemical and genetic resources

| 1 No poverty

2 Zero hunger

3 Good health and well-being

11 Sustainable cities communities

7 Affordable clean energy

8 Decent work and economic growth

9 Industry, innovation and infrastructure

12 Responsible consumption and production

| '''D''' evelopment

|-
| '''R''' egulating services

| 3 Regulation of air quality

4 Regulation of climate

5 Regulation of ocean acidification

6 Regulation of freshwater quantity, location and timing

7 Regulation of freshwater and coastal water quality

9 Regulation of hazards and extreme events

10 Regulation of organisms detrimental to humans

| 6 Clean water and sanitation

13 Climate action

| rowspan="2"| '''C''' limate adaptation and mitigation

|-
| '''S''' upporting services

| 1 Habitat creation and maintenance

2 Pollination and dispersal of seeds

8 Formation, protection and decontamination of soils and sediments

18 Maintenance of options

| 14 Life below water

15 Life on land

|-
| '''C''' ultural services

| 15 Learning and inspiration

16 Physical and psychological experiences

17 Supporting identities

| 4 Quality education

5 Gender equality

10 Reduce inequality

16 Peace, justice and strong institutions

17 Partnerships for the goals

| '''E''' nabling conditions

|}

'''Climate Change Impacts on Ecosystems and their Services'''
Climate change connects to ecosystem services through two links: climate change and its influence on ecosystems as well as its influence on services ( [[IPCC:Wg2:Chapter:Chapter-2#2.2|Section 2.2]] ). The key climatic drivers are changes in temperature, precipitation and extreme events, which are unprecedented over millennia and highly variable by regions (Sections 2.3, 3.2; Cross-Chapter Box EXTREMES in Chapter 2). These climatic drivers influence physical and chemical conditions of the environment and worsen the impacts of non-climate anthropogenic drivers including eutrophication, hypoxia and sedimentation ( [[IPCC:Wg2:Chapter:Chapter-3#3.4|Section 3.4]] ). Such changes have led to changes in terrestrial, freshwater, oceanic and coastal ecosystems at all different levels, from species shifts and extinctions, to biome migration, and to ecosystem structure and processes changes (Sections 2.4, 2.5, 3.4, Cross-Chapter Box MOVING PLATE in Chapter 5). Changes in ecosystems leads to changes in ecosystem services including food and limber prevision, air and water quality regulation, biodiversity and habitat conservation, and cultural and mental support (Sections 2.4, 3.5). Table Box 18.5.2 presents examples of climate change’s impact on ecosystems and their services from other chapters in the WGII report. The degradation of ecosystem services is felt disproportionately by people who are already vulnerable because of historical and systemic injustices, including women and children in low-income households, Indigenous or other minority groups, small-scale producers and fishing communities, and low-income countries (Sections 3.5, 4.3, 5.13).

<div id="_idContainer026" class="Box_Header-continued"></div>

Box 18.5

'''Table Box 18.5.2 |''' Examples of key risks to ecosystems from climate change and their connections to ecosystem services (ES) in the WGII report and cross-chapter papers (CCPs). (See Table 1 for the description of the categories of ES)

{| class="wikitable"
|-
! rowspan="2"| '''Climate factors'''

! rowspan="2"| '''Key risk'''

! colspan="4"| '''ES'''

|-
! '''P'''

! '''R'''

! '''S'''

! '''C'''

|-
| colspan="6"| '''''Terrestrial and freshwater ecosystems''''' '''(Chapters 2, 4, 5; CCP 1; CCP 7; CCP 3; CCP 5)'''

|-
| rowspan="5"| * Increase in average and extreme temperatures
* Changes in precipitation amount and timing
* Increase in aridity
* Increase in frequency and severity of drought
* Increased atmospheric CO 2

| Species extinction and range shifts

| '''X'''

|
| '''X'''

| '''X'''

|-
| Ecosystem structure and process change

| '''X'''

| '''X'''

|
|-
| Ecosystem carbon loss

| '''X'''

| '''X'''

|
|-
| Wildfire

|
| '''X'''

| '''X'''

|
|-
| Water cycle and scarcity

| '''X'''

| '''X'''

|
|-
| colspan="6"| '''''Ocean and coastal''''' '''(Chapter 3; CCP 1; CCP 6)'''

|-
| rowspan="5"| * Ocean warming
* Marine heatwaves
* Ocean acidification
* Loss of oxygen
* Sea level rise
* Increased atmospheric CO 2
* Extreme events

| Species extinction and range shifts

| '''X'''

|
| '''X'''

| '''X'''

|-
| Ecosystem structure and process change

| '''X'''

| '''X'''

|
|-
| Habitat loss

| '''X'''

|
| '''X'''

|
|-
| Ocean carbon sink less effective

|
| '''X'''

|
|-
| Erosion and land loss

| '''X'''

| '''X'''

|
|-
| colspan="6"| '''''Food, fibre and other ecosystem products''''' '''(Chapter 5)'''

|-
| rowspan="4"| * Global warming
* Water stress
* Extreme events
* Ocean acidification
* Salt intrusion

| Species distribution

| '''X'''

|
|-
| Timing of key biological events change

| '''X'''

|
|-
| Corp productivity and quality decrease

| '''X'''

|
|-
| Diseases and insect

| '''X'''

|
|}

'''Adaptation Practices and Enabling Conditions for CRD'''
Ecosystem protection and restoration, ecosystem-based adaptation (EBA), and nature-based solutions (NBS) can lower climate risk to people and achieve multiple benefits including food and material provision, climate mitigation and social benefits (Sections 2.6, 3.6, 4.6, 5.13, 6.3, 8.6). Table Box 18.5.3 presents some examples of ecosystem adaptation practices reported in WGII sectoral and regional chapters and CCPs, as well as their co-benefits, potential for maladaptation and enabling conditions. Many of the strategies focus on integrated systems (managing for multiple objectives and trade-offs) as well as the fair use of resources. However, there is ''limited evidence'' of the extent to which adaptation is taking place and virtually no evaluation of the effectiveness of adaptation in the scientific literature (Sections 2.6, 3.5). Enabling conditions for the successful implementation ecosystem-based practice include regional and community-based based approaches, multi-stakeholder and multi-level governance approaches, Integration of local knowledge and Indigenous knowledge, finance and social equity (Sections 2.6, 3.6).

'''Table Box 18.5.3 |''' Examples of adaptation practices and their connections to ecosystem services (ES) and climate resilient development pathways (CRDP) in the WGII sectoral and regional chapters and cross-chapter papers (CCPs). (See Table 1 for the description of the categories of ES and CRDP)

{| class="wikitable"
|-
! rowspan="2"| '''Adaptation practices (a''' '''nd –''' '''''exa''''' '''''mples''''' ''')'''

! rowspan="2"| '''Main benefit (and &amp; co-benefit; – trade off; + enabling co''' '''ndition''' '''s; X barrier and potential maladaptation)'''

! colspan="4"| '''ES'''

|-
! '''P'''

! '''R'''

! '''S'''

! '''C'''

|-
| Agroforestry (Table 2.7; Table 5 ES; [[IPCC:Wg2:Chapter:Chapter-5#5.10.4|Section 5.10.4]] ; [[IPCC:Wg2:Chapter:Chapter-5#5.12.5.2|Section 5.12.5.2]] ; Box 5.10; Table 16.2)

* ''Climate Adaptation and Maladaptation in Cocoa and Coffee Production'' (Box 5.7)

| Food provision

# '''&amp;''' Fuel (wood) provision, carbon sequestration, biodiversity and ecosystem conservation, diversification and improved economic incomes, water and soil conservation, and aesthetics

# '''+''' Secure tenure arrangements, supporting Indigenous knowledge, inclusive networks and socio-cultural values, access to information and management skill

# '''X''' Higher water demand; disruption of hydrology; loss of native biodiversity; reduced resilience of certain plants; degraded soil and water quality; improper and increased use of agrochemicals, pesticides and fertilizers

| '''***'''

| '''**'''

|
| '''**'''

|-
| Forest maintenance and restoration (Box 2.2; Table 16.2; Table Cross-Chapter Box NATURAL.1 in Chapter 2)

* ''Protected Area Planning in Thailand'' ( [[IPCC:Wg2:Chapter:Chapter-2#2.6.5.3|Section 2.6.5.3]] )
* ''Conserving Joshua trees in'' the ''Joshua National Park'' ( [[IPCC:Wg2:Chapter:Chapter-2#2.6.5.6|Section 2.6.5.6]] )
* ''Addressing Vulnerability of Peat Swamp Forests in Southeast Asia'' ( [[IPCC:Wg2:Chapter:Chapter-2#2.6.5.10|Section 2.6.5.10]] )
* ''Reduce Emissions from Deforestation and Forest Degradation (REDD+)'' ( [[IPCC:Wg2:Chapter:Chapter-5#5.6.3|Section 5.6.3.3]] ; Table 16.2)

| Ecosystem conservation

# '''&amp;''' Food provision, fuel provision, job creation, carbon sequestration, biodiversity conservation, air quality regulation, water and soil conservation, vector-borne disease control, improved mental health, cultural benefits, natural resources relative conflict prevention

# '''+''' Cooperation of Indigenous peoples and other local communities

# '''X''' Planting large-scale non-native monocultures leads to loss of biodiversity and poor climate change resilience, increased vulnerability to landslide, increased sensitivity of new tree species, reduced resilience of certain plants, high water demand, trees planted damaged buildings during heavy storms, lack of carbon rights in national legislations

| '''**'''

| '''**'''

| '''***'''

| '''**'''

|-
| Traditional practices/Indigenous knowledge and local knowledge (IKLK) (Table 2.7; [[IPCC:Wg2:Chapter:Chapter-5#5.6.3|Section 5.6.3]] ; [[IPCC:Wg2:Chapter:Chapter-5#5.1|Section 5.1]] 4.2.2; Table 16.2)

* ''Crop and Livestock Farmers on Observed Changes in Climate in the'' Sahel (Box 5.6)
* ''Karuk Tribe in Northern California'' ( [[IPCC:Wg2:Chapter:Chapter-5#5.6.3.2|Section 5.6.3.2]] )

| Food and material provision

# '''&amp;''' Carbon sequestration

# '''+''' Partnerships between key stakeholders such as researchers, forest managers and local actors, Indigenous and local knowledge

| '''***'''

| '''**'''

|
|-
| Restoring natural fire regimes (Table 2.7)

* ''Protecting Gondwanan wildfire refugia in Tasmania, Australia'' ( [[IPCC:Wg2:Chapter:Chapter-2#2.6.5.8|Section 2.6.5.8]] )

| Fire regulation

# '''&amp;''' Biodiversity conservation

|
| '''***'''

|
|-
| Natural flood risk management (Table 2.7)

* ''Natural Flood Management (NFM) in England, UK'' ( [[IPCC:Wg2:Chapter:Chapter-2#2.6.5.2|Section 2.6.5.2]] )

| Water security, flood regulation, sediment retention

# '''&amp;''' Biodiversity and ecosystem conservation

|
| '''***'''

| '''**'''

|
|-
| Coastal ecosystem conservation (Table Cross-Chapter Box NATURAL.1 in Chapter 2) (Tables 16.2, 2.7)

* ''African Penguin On-Site Adaptation'' ( [[IPCC:Wg2:Chapter:Chapter-2#2.6.5|Section 2.6.5.5]] )

| Coastal protection against sea level rise and storm surges

# '''&amp;''' Fisheries, carbon sequestration, biodiversity and ecosystem conservation, flood regulation, water purification, recreation and cultural benefits

# '''X''' NH 4 emissions, digging channels and sand walls around homes, loss of recreational value of beaches, shifted the flood impacts to poor informal urban settlers, erosion and degraded coastal lands

|
| '''**'''

| '''***'''

| '''**'''

|-
| Eco-tourism within protected areas (Table 2.7)

| Tourism

# '''&amp;''' Habitat protection

| '''***'''

|
| '''**'''

|
|-
| Aquaculture ( [[IPCC:Wg2:Chapter:Chapter-5#5.9.4|Section 5.9.4]] ; Table 16.2; Table Cross-Chapter Box NATURAL.1 in Chapter 2)

| Food provision

# '''&amp;''' Biodiversity conservation

# '''+''' Farmer incentives, participatory adaptation to context

# '''X''' Lack of financial, technical or institutional capacity; short value chains; productivity varies by system; over-fertilising; deforestation of mangroves; salt intrusion; increased flood vulnerability

| '''***'''

|
| '''*'''

|
|-
| Water–energy–food (WEF) nexus (Box 4.7)

* ''Food Water Energy Nexus in Asia'' ( [[IPCC:Wg2:Chapter:Chapter-10#10.6.3|Section 10.6.3]] )
* ''New Zealand’s Land, Water and People Nexus under a Changing Climate'' (Box 11.7)

| Water, energy and food provision

# '''X''' Insufficient data, information, and knowledge in understanding the WEF inter-linkages; lack of systematic tools to address trade-offs involved in the nexus

| '''***'''

|
|-
| Urban greening (Tables 2.7, 16.2; Table Cross-Chapter Box NATURAL.1 in Chapter 2)

* ''Ecosystem-Based Adaptation in Durban, South Africa'' ( [[IPCC:Wg2:Chapter:Chapter-2#2.6.5.7|Section 2.6.5.7]] )

| Urban flood management, water savings, urban heat island mitigation

# '''&amp;''' Reduced carbon emissions, air and noise regulation, improved mental health, energy savings, recreation and aesthetics

# '''+''' Meaningful partnerships, long-term financial commitments and significant political and administrative

# '''X''' Storage of large quantities of water in the home; water contamination; increased breeding sites for mosquitoes and flies; vectors and diseases; intensified cultivation of marginal lands; clearing of virgin forests for farmland; frequent weeding; increased competition for water and nutrients; reduced soil fertility, invasive species

|
| '''***'''

|
| '''**'''

|}

Box 18.5

Box 18.5

'''Table 18.3 |''' Specific options for facilitating the five system transitions that can support CRD

{| class="wikitable"
|-
! '''Transition'''

! '''Examples'''

! '''Reference'''

|-
| Energy systems

| Fuel switching from coal to natural gas

Expansion of renewable energy technologies

Financial incentives to promote renewable energy

Reduced energy intensity of industry

Improvements in power system resilience and reliability

Increased water use efficiency in electricity generation

Energy demand management strategies

| ( [[#Gielen--2019|Gielen et al., 2019]] ); ( [[#Mulugetta--2019|Mulugetta et al., 2019]] ); ( [[#IEA--2019|IEA et al., 2019]] ); AR6 WGIII Chapter 2

|-
| Urban and infrastructure systems

| Increased investment in physical and social infrastructure

Enhance urban and regional planning

Enhanced governance and institutional capacity supports post-disaster recovery and reconstruction ( [[#Kull--2016|Kull, 2016]] )

| ( [[#IPCC--2018b|IPCC, 2018b]] ): D3.1)

|-
| Land, oceans and ecosystems

| Expanding access to agricultural and climate services

Strengthening land tenure security and access to land

Empowering women farmers

Improved access to markets

Facilitating payments for ecosystem services

Promotion of healthy and sustainable diets

Enhancing multi-level governance by supporting local management of natural resources

Strengthening cooperation between institutions and actors

Building on local, indigenous and scientific knowledge funding, and institutional support

Monitoring and forecasting

Education and climate literacy and social learning and participation

| (IPCC, 2019 f): C2.1; (IPCC, 2019 f): C4.5; (IPCC, 2019 f): C4

|-
| Industrial systems

| Promote material efficiency and high-quality circularity

Materials demand management (IEA 2019, 2020)

Application of new processes and technologies for GHG emission reduction

Carbon pricing or regulations with provisions on competitiveness to drive innovation and systemic carbon efficiency

Low-cost, long-term financing mechanisms to enable investment and reduce risk

Better planning of transport infrastructure

Labour market training and transition support

Electricity market reform

Regulations—standards and labelling, material efficiency

Mandating technologies and targets

Green taxes and carbon pricing, preferential loans and subsidies

Voluntary action agreements, expanded producer responsibilities

Information programmes: monitoring, evaluation, partnerships, and research and development

Government provisioning of services—government procurements, technology push and market-pull

| ( [[#Åhman--2017|Åhman et al., 2017]] ; [[#Bataille--2018|Bataille et al., 2018]] ; [[#Material--2019|Material, 2019]] ); ( [[#Tanaka--2011|Tanaka, 2011]] ; [[#Schwarz--2020|Schwarz et al., 2020]] ); ( [[#Ciwmb--2003|Ciwmb, 2003]] ); ( [[#Romero%20Mosquera--2019|Romero Mosquera, 2019]] ); ( [[#Tanaka--2011|Tanaka, 2011]] ); ( [[#Ryan--2011|Ryan et al., 2011]] ; [[#Boyce--2018|Boyce, 2018]] ); ( [[#Taylor--2008|Taylor, 2008]] ); ( [[#UNEP--2018b|UNEP, 2018b]] ); ( [[#Kaza--2018|Kaza et al., 2018]] ); ( [[#Söderholm--2012|Söderholm and Tilton, 2012]] ); ( [[#Bataille--2018|Bataille et al., 2018]] ); ( [[#Ghisetti--2017|Ghisetti et al., 2017]] ); ( [[#Taylor--2008|Taylor, 2008]] ; Fischedick et al., 2014; [[#Hansen--2019|Hansen and Lema, 2019]] ); ( [[#Crippa--2019|Crippa et al., 2019]] ; [[#IEA--2019|IEA, 2019]] ); ( [[#Cavaliere--2019|Cavaliere, 2019]] ; [[#IEA--2020|IEA, 2020]] ); Vogl et al. (2018); ( [[#Pauliuk--2013|Pauliuk et al., 2013]] ; [[#Quader--2016|Quader et al., 2016]] )

|-
| Societal systems

| Inclusive governance

Empowerment of excluded stakeholders, especially women and youth

Transforming economies

Finance and technology aligned with local needs

Overcoming uneven consumption and production patterns

Allowing people to live a life in dignity and enhancing their capabilities

Involving local governments, enterprises and civil society organisations across different scales

Reconceptualising development around well-being rather than economic growth ( [[#Gupta--2017|Gupta and Pouw, 2017]] ),

Rethinking, prevailing values, ethics and behaviour

Improving decision making processes that incorporate diverse values and world views

Creating space for negotiating diverse interests and preferences

| ( [[#Fazey--2018b|Fazey et al., 2018b]] ; [[#O’Brien--2018|O’Brien, 2018]] ; [[#Patterson--2018|Patterson et al., 2018]] ); (MRFCJ, 2015; [[#Dumont--2019|Dumont et al., 2019]] ); ( [[#Popescu--2017|Popescu et al., 2017]] ; David [[#Tàbara--2018|Tàbara et al., 2018]] ); ( [[#de%20Coninck--2015|de Coninck and Sagar, 2015]] ; [[#IEA--2015|IEA, 2015]] ; [[#Parikh--2018|Parikh et al., 2018]] ); ( [[#Dearing--2014|Dearing et al., 2014]] ; [[#Häyhä--2016|Häyhä et al., 2016]] ; [[#Raworth--2017|Raworth, 2017]] ); ( [[#Klinsky--2018|Klinsky and Winkler, 2018]] ); ( [[#Hajer--2015|Hajer et al., 2015]] ; [[#Labriet--2015|Labriet et al., 2015]] ; [[#Hale--2016|Hale, 2016]] ; [[#Pelling--2016|Pelling et al., 2016]] ; [[#Kalafatis--2017|Kalafatis, 2017]] ; [[#Lyon--2018|Lyon, 2018]] ); ( [[#Holden--2017|Holden et al., 2017]] ); ( [[#Cundill--2014|Cundill et al., 2014]] ; [[#Butler--2016|Butler et al., 2016]] ; [[#Ensor--2016|Ensor, 2016]] ; [[#Fazey--2016|Fazey et al., 2016]] ; [[#Gorddard--2016|Gorddard et al., 2016]] ; [[#Aipira--2017|Aipira et al., 2017]] ; Chung [[#Tiam%20Fook--2017|Tiam Fook, 2017]] ; [[#Maor--2017|Maor et al., 2017]] ); ( [[#O’Brien--2015|O’Brien and Selboe, 2015]] ; [[#Gillard--2016|Gillard et al., 2016]] ; [[#DeCaro--2017|DeCaro et al., 2017]] ; [[#Harris--2018|Harris et al., 2018]] ; [[#Lahn--2018|Lahn, 2018]] ; [[#Roy--2018|Roy et al., 2018]] ); Sections 5.6.1 and 5.5.3.1

|}

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<span id="accelerating-transitions"></span>