12. Beyond adaptation: Systemic interlinkages with mitigation and other natural systems

This chapter draws on contributions to the horizontal project carried out under the responsibility of the Environment Policy Committee.

The rapid increase in climate change impacts necessitates not only mitigation and adaptation objectives to be pursed in tandem but consideration of other socio-economic and environmental objectives that intersect with these efforts. Climate risks pose considerable challenges to the net-zero transition itself, and resilience to climate impacts is key to a resilient transition. Furthermore, although the impacts of climate change are initially felt locally, the interconnectedness and interdependence of different economic sectors, communities, and ecosystems means that these impacts cascade across a number of different systems.

Exploring how approaches to systemic resilience can address these systemic interlinkages and integrate adaptation and mitigation, this chapter highlights the importance of other natural systems for climate policy. Specifically, examples of biodiversity and oceans, and the role of nature-based solutions, demonstrate how synergies across these systems can be harnessed to produce win-win policy options.

Both adaptation and mitigation policies have the potential to significantly reduce the impacts of climate change. In the long run, mitigation responses will shape future adaptation needs and influence climate resilience pathways. Synergies between adaptation and mitigation efforts can foster climate resilience effectively. For example, efforts to restore forests or mangroves can increase ecosystems’ carbon storage capacity while also helping to reduce weather-related risks such as landslides or coastal storm surges. Fighting deforestation, reducing the risk of wildfires and encouraging afforestation preserve carbon sinks and soil stability while protecting communities. Similarly, agricultural soil management can promote carbon sequestration (Henderson et al., 2022[1]) while improved agricultural practices can preserve water run-offs or prevent droughts (OECD, 2014[2]). Agriculture, forestry and land management, water management and urban planning are key policy areas where synergies between mitigation and adaptation can be found.

In addition to these potential synergies between adaptation and mitigation objectives, building resilience to climate impacts is also integral to the resilience of the net-zero transition itself. For example, energy systems will need to be able to withstand extreme weather events to ensure a smooth transition to low carbon energy sources. Excessive losses and damages which could have been minimised through effective adaptation policies may divert funds from mitigation efforts. The distributional outcomes of climate impacts may further exacerbate inequalities and concerns about a just transition. These examples underline the need to consider adaptation and resilience together.

Just as synergies between mitigation and adaptation actions can render climate policies more effective, there are also trade-offs that emerge from the complexity and diversity of adaptation-mitigation linkages across geographical scales. Some adaptation actions can exacerbate climate change, and reciprocally, mitigation actions can exacerbate climate risk if they increase the vulnerability and exposure of people, ecosystems and assets. As illustrated in Figure 12.1 above, growing investment in air conditioning to effectively combat heatwaves leads to higher energy consumption and thus increases greenhouse gas (GHG) emissions. Similarly, desalination plants are an important adaptation measure to cope with water shortages but their use increases energy demand and therefore, potentially, GHG-intensive sources of energy production. Paying for green set-aside in agriculture, i.e. land that is removed from food production, may have positive effects in terms of greenhouse gas emissions reduction and agricultural productivity but may negatively impact adaptation efforts (Lankoski, Ignaciuk and Jésus, 2018[4]).

There are also trade-offs between climate action and the achievement of other environmental objectives. Building a hydropower plant can support mitigation (renewable power generation) and adaptation (water reservoir for irrigation) but can also create new flood-prone zones, thereby hindering adaptation efforts. In addition, the construction of hydropower plants can lead to flooding and destruction of unique ecosystems and biodiversity (OECD, 2021[5]). These trade-offs are context-specific and define the long-term success of climate action.

Countries are increasingly recognising the importance of adaptation-mitigation linkages. A recent review by the OECD shows that almost all G20 countries mentioned adaptation-mitigation linkages in their NAPs or NDCs (OECD, 2021[5]). For example, Italy dedicates an entire section to adaptation-mitigation linkages in its National Climate Change Adaptation Strategy.1 The UK’s Environmental Land Management schemes, designed in consultation with farmers, promote good soil management practices to serve both mitigation and adaptation.

Notwithstanding these recent developments, climate change adaptation and mitigation policies have historically been largely addressed separately (OECD, 2021[5]). This is partly explained by the fact that limiting climate change through mitigation action has global public good benefits, while those of adaptation actions are mostly accrued locally (Swart and Raes, 2007[6]). This creates different needs and levels of co-ordinating action. The type of knowledge needed to inform adaptation and mitigation policies is also different. While mitigation policy is grounded in information on the source, type and amount of GHG generated, adaptation policy is informed by assessing the risks posed by different projected climate change impacts. As such, distinct stakeholders are involved in the design and implementation of adaptation and mitigation policies (Denton et al., 2014[7]).

While most countries mention the importance of exploiting synergies between adaptation and other environmental goals, often in the introduction to planning or strategy documents or in the context of co-ordination mechanisms, linkages are seldom discussed in depth and specific measures are rarely detailed. The recognition of linkages in national policy documents needs to be complemented with implementation strategies and clear actions. For example, better collaboration between mitigation and adaptation stakeholders could facilitate sharing of common background and knowledge about trade-offs and synergies. Strengthening reporting mechanisms of countries’ climate actions could help better capture how countries incorporate these synergies, offering good-practice examples and enabling learning across countries (Adaptation Committee, 2022[8]). Future research could focus on developing or adapting decision-support tools to facilitate alignment considerations for project managers. Tools such as cost benefit analysis or multi-criteria analysis can support the analysis of complex and context-specific trade-offs (OECD, 2020[9]). Appraisals of climate risk should be mainstreamed within investment decisions. The “do no significant harm'” concept of the EU's sustainable finance taxonomy, which prevents an investment from being defined as sustainable if it harms any of six EU-identified environmental objectives, can be used as a framework to shed light on and manage possible trade-offs (OECD, 2020[9]).2

A primary example of the complexity and interconnectedness of systems is the intertwined crises of biodiversity loss and climate change. Biodiversity is defined as the variability among living organisms from all sources including, among others, terrestrial, marine and other aquatic ecosystems and the ecological complexes of which they are part; this includes diversity within species, between species and of ecosystems (CBD, 1992[10]). Climate trends and extremes are pushing marine and terrestrial ecosystems closer to thresholds and tipping points (see Chapter 2) (Harris et al., 2018[11]). Allowing global average temperature to increase to 2°C above pre-industrial levels rather than holding it to 1.5°C could be catastrophic for some species (Smith et al., 2018[12]). Reciprocally, changes in biodiversity affect the climate system, especially through their impacts on nitrogen, carbon and water cycles (Pörtner et al., 2021[13]).

Biodiversity – an integral component of natural capital – provides critical ecosystem services upon which all life on Earth depends. These ecosystem services include pollination, nutrient cycling, erosion control, carbon sequestration and natural hazard protection. Biodiversity and ecosystem services underpin all economic and social systems, and so are fundamental for thinking around resilience.

Yet, biodiversity is declining at an unprecedented rate with one million plant and animal species facing extinction, and terrestrial, freshwater and marine ecosystems being driven towards tipping points (IPBES, 2019[14]). According to the literature on planetary boundaries, the biosphere integrity boundary that refers to the functional integrity of ecosystems, hence biodiversity, has already been transgressed, with considerable implications for the resilience of natural systems.

Numerous interlinkages exist between biodiversity loss and climate change. For example, marine and terrestrial ecosystems are natural carbon sinks, with an annual gross sequestration equivalent to about 60% of global anthropogenic emissions (IPBES, 2019[14]). But biodiversity loss is reducing ecosystems’ natural capacity to store carbon and is contributing to greenhouse gas emissions, thereby aggravating climate change. Deforestation alone accounts for an estimated 10% of anthropogenic greenhouse gas emissions.

Tackling biodiversity loss could therefore make an important contribution to climate mitigation efforts. Conserving, restoring and improving the management of forests, grasslands, wetlands and agricultural lands could deliver an estimated 23.8 gigatonnes of cumulative CO2 emission reductions by 2030 (OECD, 2021[15]). The ecosystem services delivered by healthy, intact ecosystems can help protect humans from slow onset and extreme climate events. For example, wetlands can absorb surplus water during floods and be a water source during droughts, while forests can help stabilise land, reducing the risk of erosion, desertification, and landslides. Biodiverse ecosystems are both more resilient and offer more climate benefits than growing monocultures.

Nature-based solutions (NbS) can play an important role not only in helping ecosystems, communities and industries build resilience to climate impacts but also by mitigating climate change through emissions sequestration and broadly improving human well-being. For example, wetland restoration, revegetation or reforestation in river deltas and along shorelines and the protection of coastal ecosystems such as mangroves, saltmarshes or shellfish would all increase biodiversity, enhance coastal resilience to extreme weather and natural disasters, provide other co-benefits such as water purification or soil enhancement, and sequester carbon emissions.

While obvious synergies between climate and biodiversity action exist, some actions to mitigate and adapt to climate change can negatively affect biodiversity (e.g. large-scale expansion of bioenergy and monoculture plantations, renewable energy infrastructure, and construction of dams and seawalls). This requires careful planning and management. The mitigation pathways countries choose will determine the extent of potential trade-offs between climate and biodiversity action (OECD, 2021[15]). These trade-offs highlight the importance of considering systemic interactions in climate policy making. The resilience of the transition will rely not only on the ability to safeguard climate-specific policies, but also the extent to which these policies trade off climate-relevant components of other systems.

These policy interlinkages are becoming increasingly acknowledged within the policy sphere. The Kunming-Montreal Global Biodiversity Framework, agreed in December 2022 at CBD COP15, includes four goals to be achieved by 2050 and 23 targets to be achieved by 2030. Target 8 specifically refers to climate change, stating that by 2030 Parties should: “Minimize the impact of climate change and ocean acidification on biodiversity and increase its resilience through mitigation, adaptation, and disaster risk reduction actions, including through nature-based solutions and/or ecosystem-based approaches, while minimizing negative and fostering positive impacts of climate action on biodiversity.”

To ensure coherence and alignment of climate and biodiversity policies, the OECD report Towards Sustainable Land Use: Aligning Biodiversity, Climate and Food Policies emphases the need to:

  • Strengthen coherence across relevant national strategies and plans (e.g. for biodiversity, climate and other key areas), and ensure that these have specific and measurable targets.

  • Strengthen institutional co-ordination between different ministries related to climate, biodiversity and other key areas, including for examples via the creation of inter-ministerial committees.

  • Better integrate spatial data into land- and sea-use decision making.

  • Examine opportunities to harness synergies in the development of policy instruments so as to better address climate and biodiversity simultaneously, such as through payments for ecosystem services, among other policy instruments (OECD, 2020[16]).

Further concerted efforts are needed to identify and address potential trade-offs across policy objectives and instruments, e.g. between the expansion of renewable energy and grid infrastructure, and the protection of nature. As climate change is the fastest growing driver of biodiversity loss, transitioning away from fossil fuels is fundamental to achieving global biodiversity objectives. However, the growing demand for low-carbon electricity requires more land and sea to be dedicated to power infrastructure, posing new and growing risks to biodiversity.

The potential impacts of renewable energy and grid infrastructure are diverse. They include, among others, direct species mortality (e.g. collision of birds and bats with powerlines and wind turbines); habitat loss and degradation (e.g. from conversion of land for solar energy facilities and mining impacts); habitat fragmentation and barrier effects on species movement; behavioural impacts (e.g. avoidance behaviour), ecosystem services impacts and complex indirect impacts. These impacts can accumulate across projects and across time.

To ensure the transition to low-carbon electricity is nature-positive, decision makers must mainstream biodiversity into low-carbon pathways and renewable energy policy, planning, programme and project cycles. Adopting low energy demand pathways to achieve the Paris Agreement goals is fundamental for reducing conflicts between renewable energy and biodiversity. It is also important that countries consider biodiversity when developing their energy portfolios and determining where and how to deploy renewable energy and transmission infrastructure. Failure to mainstream biodiversity could further erode natural capital, thereby increasing economic and societal risks, and undermining efforts to achieve climate goals.

Conversely, when the low-carbon transition is planned in a systematic way that explicitly addresses biodiversity, synergies can be harnessed, enhancing resilience. For example, deploying solar photovoltaics in degraded land together with ecological restoration activities that generate habitat for pollinators could help meet climate and energy goals, while reducing climate impacts on biodiversity, promoting nature recovery and supporting agriculture.

Another example of the interlinkages between different natural systems are the oceans and climate change. More than two-thirds of the Earth’s surface is covered by oceans, which play an essential role in regulating global climate patterns, foods chains, and general ecosystem health. Climate change also has important consequences for oceans. Biological, chemical and physical feedback loops threaten to cross irreversible tipping points with catastrophic implications for ocean ecosystems, the climate system, and interlinked socio-economic and natural systems. At the same time, the ocean acts as a key carbon sink, and since the industrial revolution has absorbed 30-40% of emitted CO2 and 93% of excess global warming (Seeger, 2021[17]).

This absorptive quality of the ocean, however, comes with considerable consequences. Ocean acidification, warming and deoxygenation have severe impacts on marine ecosystems. Marine species such as coral are sensitive to the slightest change in temperature and ocean warming has already led to wide-spread coral bleaching and will likely result in the irreversible loss of most coral ecosystems (OECD, 2022[18]). This in turn has profound knock-on effects, including a loss of key habitat for marine life with impacts felt along the ocean food-chain, and exposing coastlines to extreme weather. Deoxygenation has already led to the formation of large ocean “dead-zones” where low oxygen levels prevent the survival of aquatic life. Acidification compromises the survival of organisms sensitive to ocean Ph levels, such as shellfish, in turn, affecting ocean ecosystems and food-chains (Seeger, 2021[17]).

These impacts of global warming on ocean ecosystems have been labelled as “silent” tipping points due to a general lack of awareness of their existence (Heinze et al., 2021[19]). While tipping points literature points to the potential for a collapse in ocean circulation systems such as the Atlantic Meridional Overturning Circulation (AMOC) (see Chapter 2), warming, acidification and deoxygenation can also lead to irreversible changes with profound implications. However, the complex and heterogeneous effects of these climate impacts on marine life make it difficult to understand how climate change is affecting oceans, and what changes to expect in the future.

Ocean ecosystems play an essential role throughout socio-economic systems, and changes to these ecosystems, as brought about by climate change, can have a profound impact, socially and economically. Some 4.5 billion people (half the world’s population) obtain more than 15% of their protein intake from the ocean (IPCC, 2019[20]). Fisheries and aquaculture employ around 60 million people globally, with coastal populations particularly reliant on the oceans for their livelihoods (FAO, 2020[21]). The impacts of climate change on fisheries differ across regions, and according to the scale of the fisheries, with some projected to increase catches, while others experience a significant decrease (FAO, 2020[21]).

Forty per cent of the world’s population and 75% of its largest cities are located in coastal zones. As such, much of the world’s population and urban infrastructure is exposed to increasingly severe weather and sea-level rise. From 2000-2019, storms killed over 200 000 people and caused USD 1.4 trillion in damage globally. This figure is projected to increase significantly due to climate change, with coastal flooding projected to threaten 360 million people and 4% of global GDP annually by 2100 (UNDRR, 2020[22]).

It is clear that climate change will have a profound impact on the ocean, its ecosystems, and the large populations and industries relying on them. In addition to climate pressures, local stressors such as overfishing, eutrophication, chemical pollution and habitat destruction further compromise the health of ecosystems and their resilience to climate impacts. Over half of coastal ecosystems have been lost since 1900, one-third of fish stocks are overexploited, and 90% of waste entering the ocean remains close to shore (Seeger, 2021[17]).

These pressures highlight the need to combine climate mitigation and adaptation policies with ocean specific measures in order to safeguard the health of ocean ecosystems. The highly complex global ocean network and its myriad of interlinkages with other natural and socio-economic systems requires systems thinking and the development of systemic resilience to design policies for a sustainable and resilient ocean.

Given the fundamental uncertainties surrounding ocean systems and the risk of crossing the thresholds of irreversible tipping points, policy makers should err on the side of caution in building ocean resilience. Adapting fisheries management policies to ecosystem changes, for example, would make fisheries more resilient to potential shocks. This requires reducing overall mortality rates and then maintaining flexible management practices that can be adapted to future events and emerging knowledge. Maritime special planning and marine-protected areas are two further policy tools with considerable promise for enhancing sustainability and resilience. Both, however, rely on robust scientific evidence in order to monitor ecosystems, adapt to ecosystems changes, and ensure special planning and protected areas are implemented in appropriate locations.

Given its interlinkages with the climate and socio-economic systems, the oceans hold considerable promise for marine nature-based solutions (NbS). However, in order to take full advantage of NbS in ocean systems, certain barriers to their implementation need to be overcome.

As with climate impacts generally, developing countries, especially small island developing states (SIDS) and coastal least developed countries (LDCs), are particularly vulnerable to shocks to ocean and coastal systems, and often lack the adaptive capacity and investment support needed to build resilience. Only 56% of overseas development assistance (ODA) channelled towards ocean-related sectors focuses on increasing climate change adaptation, mitigation or sustainability (USD 1.6 billion in 2019) (OECD, 2020[23]). However, the oceans, much like the climate, are a global system. Building systemic resilience is only possible if the international community works together to manage the risks of climate change and other local stressors.

Interlinkages between the ocean, climate, human and other natural systems highlight the importance of ensuring a sustainable and resilient ocean to avoid risks not only to marine ecosystems but also to the people and economic activities that depend on them. Policies for ocean resilience are highly specific in many ways but also bear strong parallels with climate policies that are discussed elsewhere in this report. This includes the importance of long-term thinking and integrated policies across systems; and social considerations such as the needs of coastal communities; the vulnerability of developing countries; the need for international co-operation; and the challenges of communicating science.

Reaching net-zero emissions alone will not be enough to steer humanity towards a safe planetary operating space. The climate system is inextricably linked with other systems such as biodiversity and the oceans. Such interlinkages require careful consideration and a systemic approach to building resilience that reaches across systems boundaries.

Nature-based solutions (NbS) can play an important role in harnessing synergies between adaptation and mitigation, as well as with biodiversity (OECD, 2021[24]). NbS are defined by the OECD as “measures that can protect, sustainably manage, and restore nature, with the goal of maintaining and enhancing ecosystem services to help address a variety of social, environmental and economic challenges” (OECD, 2020[25]), such as protecting and restoring coastal habitats and upland forests or greening urban spaces (OECD, 2021[5]).3 NbS can encompass a range of approaches; such as ecological disaster risk reduction, ecosystem-based adaptation, green infrastructure or natural climate solutions.

Although usually defined as opposite to “traditional" or "grey" infrastructure, NbS can be complementary and even combined with it (OECD, 2020[26]). Nature-based solutions can be an effective complement to existing or new infrastructure development to reinforce adaptation of the built environment through natural measures. For example, the creation of permeable surfaces around infrastructure assets reduces flood risk, and fuel breaks around infrastructure assets protect infrastructure in wildfire hazard areas. In an urban context, buildings can be retrofitted with NbS for cooling and to reduce the radiation effect during heatwaves (OECD, 2023[27]).

The potential of nature-based solutions to address the causes and consequences of climate change has been recognised by policy makers at the national and international levels. The Paris Agreement, the Sendai Framework, and the Kunming-Montreal Global Biodiversity Framework, as agreed at CBD COP15, all recognise the potential of NbS. Following these international statements, two-thirds of the signatories to the Paris Agreement have mentioned the development of NbS as a main objective to adapt to and/or mitigate climate change in their nationally determined contributions (NDCs) (Seddon et al., 2019[28]). The majority of OECD countries also make NbS an explicit priority in their National Adaptation Plans (OECD, 2021[5]). Similarly, almost half of 210 cities that submitted adaptation plans to the Carbon Disclosure Project in 2016 included measures related to NbS, such as the creation of green spaces for climate change adaptation (UNEP, 2021[29]).

In addition to effectively mitigating climate change and its future impacts, NbS can be win-win or no-regret adaptation options. This is true as long as strong social and environmental safeguards are applied in their planning, implementation and management, with special focus on the rights of local and indigenous populations and intersectionality. As NbS produce co-benefits such as ecosystem services, they remain beneficial even in the absence of the climate mitigation and climate resilience benefits that they provide (Hallegatte, 2009[30]). For example, Sweden has invested EUR 22 million in natural measures to drain the cities of Augustenborg and Malmö. These green solutions have reduced water run-off by 50% and have also led to a substantial increase in local biodiversity (OECD, 2020[26]).

As a cost-effective adaptation solution, nature-based solutions also generate significant economic benefits. For example, NbS interventions to restore riverbeds in Europe have increased flood protection while also enhancing agricultural production, carbon sequestration and recreation, for a total net economic benefit of EUR 1400 per hectare per year (Vermaat et al., 2015[31]).

The economic benefits of NbS often far outweigh those of grey infrastructure. In the United States, NbS as coastal defences are two to five times more cost-effective than grey infrastructure (Narayan et al., 2016[32]). When strategically planned, NbS can also enhance the resilience of traditional infrastructure to climate risks, reducing their vulnerability to climate impacts and their operational costs while also extending their lifetime (OECD, 2020[33]). Investments in NbS can also stimulate job creation.

Despite their potential, the use of nature-based solutions remains piecemeal (Kapos et al., 2019[34]; Browder et al., 2019[35]). Although NbS projects are multiplying, they are often limited to small-scale and pilot projects (Tremolet et al., 2019[36]). A recent OECD survey on the implementation of NbS to address water-related climate risks shows that less than 10% of water managers who responded believed that progress in the implementation of NbS is in line with their country's ambitions (OECD., 2021[37]).

The implementation of NbS is impeded by a lack of awareness of their uses and benefits. In addition, several practical limitations present obstacles. First, it is difficult to assess and quantify the benefits of NbS and thus prove their effectiveness as adaptation solutions, especially in comparison to the short-term and easily observable benefits of so-called "grey" solutions (OECD, 2020[26]). Some natural solutions such as mangroves or forests can be slow to develop and deliver their full adaptation benefits (Kabisch et al., 2016[38]). Moreover, current evaluation tools are not well suited for NbS, and often fail in assessing their benefits in comparison to “traditional” grey options (Tremolet et al., 2019[36]). Second, while the flexibility of NbS in the face of future climate variability is an asset, their sensitivity to their evolving environment, including climate hazards, can undermine their effectiveness. For example, droughts and rising temperatures can lead to wildfires. As reforestation takes time, communities will remain unprotected for many years, and the capacity of forest to store carbon will be altered for decades (Anderegg et al., 2020[39]). In implementing NbS it is of course critical to ensure they are aligned with existing planning and regulatory arrangements so as to safeguard local communities.

More broadly, nature-based solutions are also more difficult to implement than individual adaptation solutions because they rely on a wide set of environmental and socio-economic parameters (Calliari, Staccione and Mysiak, 2019[40]). For example, coral reefs are sensitive to rising ocean temperatures but also to water pollution (DUBINSKY and STAMBLER, 1996[41]). While 70 to 90% of coral reefs could disappear if global average temperature increase reaches 1.5°C (IPCC, 2021[42]), maintaining coral reefs also requires concerted management of diffuse pollution potentially emanating from a large number of sources, located over a wide geographical area.

Three main policy challenges to the implementation of NbS have been highlighted in the literature (OECD., 2021[37]). First, due to a lack of knowledge of their effectiveness, NbS are often overlooked by climate policy makers. Second, assessing the economic costs and benefits of NbS remains difficult, posing a barrier to policy makers wishing to justify NbS vis-à-vis other policy options as well as potential investors or funding institutions needed to finance NbS projects. Finally, NbS remain ill-defined within climate policy taxonomies and legal structures, posing significant regulatory challenges (Kabisch et al., 2016[38]; Kapos et al., 2019[34]; OECD, 2020[26]; Browder et al., 2019[43]).

A range of policy options can be implemented to overcome these problems (OECD, 2021[44]; OECD, 2020[26]). First, more information is needed to better assess the potential of NbS, especially in comparison to or in combination with grey solutions. Overcoming the perception that NbS are too expensive and technically too difficult to implement relies on international scientific co-operation to address knowledge and data gaps. Governments can support the generation of information by funding pilot programmes or subsidising research. Platforms or open data can then disseminate information to different stakeholders to share the knowledge produced. Second, public institutions can provide a space for technical assistance and knowledge sharing to help stakeholders better understand the role of NbS and co-ordinate their actions. Third, the revision of land use regulations and building standards should encourage the use of NbS. Fourth, while increased awareness of NbS as a cost-effective solution to adapt to climate change will encourage its implementation, dedicated funding for NbS will still be needed.

The implementation of NbS can also be supported by developing sustainable finance solutions such as ecosystem insurance products. Incorporating NbS into risk assessment frameworks and enhancing data and modelling capacity in order to quantify climate risks and the benefits of NbS in their management is essential. Finally, implementing NbS requires clear communication with local communities, building public support and buy-in.

The examples of systemic interactions explored in this chapter underscore the need for a systemic approach to resilience. However, more often than not, policy efforts remain confined to individual systems or policy areas. This is well illustrated by as-of-yet minimal co-ordination across adaptation and mitigation actions despite clear synergies between the two. While efforts to address this are underway, the quickening pace of climate change necessitates an acceleration. Here, awareness of the importance of resilience to climate impacts for a resilient net-zero transition may offer an opportunity to enhance co-ordination. Systemic interlinkages with other natural systems such as biodiversity and the oceans, and the ability for nature-based solutions (NbS) to make the most of synergies between different policy objectives further highlight the importance of taking a broad approach. Given the cost-effectiveness of many NbS/ecosystems in sequestering carbon, biodiversity policies should look to climate mitigation finance for funding.

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Notes

← 1. https://www.minambiente.it/notizie/strategia-nazionale-di-adattamento-ai-cambiamenti-climatici-0.

← 2. The six objectives are: (i) Climate change mitigation, (ii) Climate change adaptation, (iii) Sustainable use and protection of water and marine resources, (iv) Transition to a circular economy, waste prevention and recycling, (v) Pollution prevention and control, (vi) Protection of healthy ecosystems.

← 3. The United Nations Environment Agency has adopted a very similar definition of Nature-based Solutions, as “actions to protect, conserve, restore, sustainably use and manage natural or modified terrestrial, freshwater, coastal and marine ecosystems, which address social, economic and environmental challenges effectively and adaptively, while simultaneously providing human well-being, ecosystem services and resilience and biodiversity benefits.” https://www.naturebasedsolutionsinitiative.org/news/united-nations-environment-assembly-nature-based-solutions-definition/

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