Current nationally stated mitigation ambitions until 2030 will result in a global warming of about 3°C by 2100, with warming continuing afterwards.
Limiting global warming to 1.5°C requires rapid and far reaching transitions in energy, land, urban and infrastructure, including transport and buildings, and industrial systems.
Social justice and equity are core aspects of climate-resilient development pathways that aim to limit global warming to 1.5°C.
An IPCC special report on the impacts of global warming of 1.5°C above pre-industrial levels and related global greenhouse gas emission pathways, in the context of strengthening the global response to the threat of climate change, sustainable development, and efforts to eradicate poverty.
This Report responds to the invitation for IPCC to provide a Special Report in 2018 on the impacts of global warming of 1.5°C above pre-industrial levels and related global greenhouse gas emission pathways contained in the Decision of the 21st Conference of Parties of the United Nations Framework Convention on Climate Change to adopt the Paris Agreement.
The IPCC accepted the invitation in April 2016, deciding to prepare this Special Report on the impacts of global warming of 1.5°C above pre-industrial levels and related global greenhouse gas emission pathways, in the context of strengthening the global response to the threat of climate change, sustainable development, and efforts to eradicate poverty.
This Summary for Policymakers (SPM) presents the key findings of the Special Report, based on the assessment of the available scientific, technical and socio-economic literature relevant to global warming of 1.5°C and for the comparison between global warming of 1.5°C and 2°C above pre-industrial levels.
Core Concepts Central to this Special Report
Global mean surface temperature (GMST): Estimated global average of near-surface air temperatures over land and sea ice, and sea surface temperatures over ice-free ocean regions, wrth changes normally expressed as departures from a value over a specified reference period. When estimating changes in GMST, near-surtace air temperature over both land and oceans are also used.
Pre industrial: The multi century period prior to the onset of large scale industrial activity around 1850. The reference period 1850-1900 is used to approximate pre-industrial GMST.
Global warming: The estimated increase in GMST averaged over a 30-year period, or the 30-year period centred on a particuiar year or decade, expressed relative to pre-industrial levels unless otherwise specified. For 30-year periods that span past and future years, the current multi-decadal warming trend is assumed to continue.
Net zero C02 emissions: Net zero carbon dioxide (CO2) emissions are achieved when anthropogenic C02 emissions are balanced globally by anthropogenic C02 removals over a specified period.
Carbon dioxide removal (CDR): Anthropogenic activities removing CO2 from the atmosphere and durably storing it in geological, terrestrial, or ocean reservoirs, or in products. It includes existing and potential anthropogenic enhancement of biological or geochemical sinks and direct air capture and storage, but excludes natural C02 uptake not directly caused by human activities.
Total carbon budget: Estimated cumulative net global anthropogenic C02 emissions from the pre-industrial period to the time that anthropogenic C02 emissions reach net zero that would result, at some probability, in limiting global warming to a given level, accounting for the impact of other anthropogenic emissions.
Remaining carbon budget: Estimated cumulative net global anthropogenic CO2 emissions from a given start date to the time that anthropogenic C02 emissions reach net zero that would result, at some probability, in limiting global warming to a given level, accounting for the impact of other anthropogenic emissions.
Temperature overshoot: The temporary exceedance of a specified level of global warming.
Emission pathways: In this Summary for Policymakers, the modelled trajectories of global anthropogenic emissions over the 21st century are termed emission pathways. Emission pathways are classified by their temperature trajectory over the last century: pathways giving at least 50% probability based on current knowledge of limiting global warming to below 1.5°C are classified as ‘no overshoot’; those limiting warming to below 1.6°C and returning to 1.5°C by 2100 are classified as ‘1.5°C limited overshoot’; while those exceeding 1.6°C but still returning to 1.5°C by 2100 are classified as ‘higher overshoot’.
Impacts: Effects of climate change on human and natural systems. Impacts can have beneficial or adverse outcomes for livelihoods, health and well-being, ecosystems and species, services, infrastructure, and economic, social and cultural assets.
Risk: The potential for adverse consequences from a climate related hazard for human and natural systems, resulting from the interactions between the hazard and the vulnerability and exposure of the affected system. Risk integrates the likelihood of exposure to a hazard and the magnitude of its impact. Risk also can describe the potential for adverse consequences of adaptation or mitigation responses to climate change.
Climate-resilient development pathways (CRDPs): Trajectories that strengthen sustainable development at multiple scales and efforts to eradicate poverty through equitable societal and systems transitions and transformations while reducing the threat of climate change through ambltious mitigation, adaptation and climate resilience.
Understanding Global Warming of 1.5°C
Human activities are estimated to have caused approximately 1.0°C of global warming above pre industrial levels, with a likely range of 0.8°C to 1.2°C. Global warming is likely to reach 1.5°C between 2030 and 2052 if it continues to increase at the current rate.
Reflecting the long term warming trend since pre industrial times, observed global mean surface temperature (GMST) for the decade 2006-2015 was 0.87°C (likely between 075°C and 099°C) higher than the average over the 1850-1900 period. Estimated anthropogenic global warming matches the level of observed warming to within 120% (likely range). Estimated anthropogenic global warming is currently increasing at 0.2°C (likely between 0.1°C and 0.3°C) per decade due to past and ongoing emissions.
Radiative forcing or climate forcing is the difference between insolation (sunlight) absorbed by the Earth and energy radiated back to space. The influences that cause changes to the Earth’s climate system altering Earth’s radiative equilibrium, forcing temperatures to rise or fall, are called climate forcings. Positive radiative forcing means Earth receives more incoming energy from sunlight than it radiates to space. This net gain of energy will cause warming. Conversely, negative radiative forcing means that Earth loses more energy to space than it receives from the sun, which produces cooling.
Warming greater than the global annual average is being experienced in many land regions and seasons, including two to three times higher in the Arctic. Warming is generally higher over land than over the ocean.
Trends in intensity and frequency of some climate and weather extremes have been detected over time spans during which about 0.5°C of global warming occurred.
This assessment is based on several lines of evidence, including attribution studies for changes in extremes since 1950.
Warming from anthropogenic emissions from the pre industrial period to the present will persist for centuries to millennia and will continue to cause further long term changes in the climate system, such as sea level rise, with associated impacts, but these emissions alone are unlikely to cause global warming of 1.5°C.
Anthropogenic emissions (including greenhouse gases, aerosols and their precursors) up to the present are unlikely to cause further warming of more than 0.5°C over the next two to three decades or on a century time scale.
Reaching and sustaining net zero global anthropogenic C02 emissions and declining net non-CO2 radiative forcing would halt anthropogenic global warming on multi-decadal time scales. The maximum temperature reached is then determined by cumulative net global anthropogenic CO2 emissions up to the time of net zero CO2 emissions and the level of non-CO2 radiative forcing in the decades prior to the time that maximum temperatures are reached. 0n longer time scales, sustained net negative global anthropogenic C02 emissions and/or further reductions in non-CO2 radiative forcing may still be required to prevent further warming due to Earth system feedbacks and to reverse ocean acidification and will be required to minimize sea level rise.
Climate-related risks for natural and human systems are higher for global warming of 1.5°C than at present, but lower than at 2°C. These risks depend on the magnitude and rate of warming, geographic location, levels of development and vulnerability, and on the choices and implementation of adaptation and mitigation options.
Impacts on natural and human systems from global warming have already been observed. Many land and ocean ecosystems and some of the services they provide have already changed due to global warming.
Future climate-related risks depend on the rate, peak and duration of warming. In the aggregate, they are larger if global warming exceeds 1.5°C before returning to that level by 2100 than if global warming gradually stabilizes at 1.5°C, especially if the peak temperature is high (e.g., about 2°C). Some impacts may be long-lasting or ireversible, such as the loss of some ecosystems.
Adaptation and mitigation are already occurring. Future climate-related risks would be reduced by the upscaling and acceleration of far reaching, multilevel and cross-sectoral climate mitigation and by both incremental and transformational adaptation.
Figure SPM.1 Panel a: Observed monthly global mean surface temperature (GMST, grey line up to 2017, from the HadCRUTA, GISTEMP, Cowtan-Way, and NCAA datasets) change and estimated anthropogenic global warming (Solid orange line up to 2017, with orange shading indicating assessed likely range). Orange dashed arrow and horizontal orange error bar show respectively the central estimate and likely range of the time at which 1.5°C is reached if the current rate of warming continues. The grey plume on the right of panel a shows the likely range of warming responses, computed with a simple climate model, to a stylized pathway (hypothetical future) in which net C02 emissions (grey lines in panels b and c) decline in a straight line from 2020 to reach net zero in 2055 and net non-C02 radiative forcing (grey line in panel d) increases to 2030 and then declining. The blue plume in panel a) shows the response to faster CO2 emissiins reductions (blue line in panel b), reaching net zero in 2040, reducmg cumulative C02 emissions (panel c). The purple plume shows the response to net CO2 emissions declining to zero in 2055, with net non-CO2 forcing remaining constant after 2030. The vertical error bars on right of panel a) show the likely ranges (thin lines) and central terciles (33rd – 66th percentiles, thick lines) of the estimated distribution of warming in 2100 under these three stylzed pathways. Vertical dotted error bars in panels b, c and d show the likely range of historical annual and cumulative global net CO2 emissions In 2017 (data from the Global Carbon Preject) and of net non-CO2 radiative forcing in 2011 from AR5, respectlvely. Vertical axes in panels c and d are scaled to represent approximately equal effects on GMST.
Projected Climate Change, Potential Impacts and Associated Risks
Climate models project robust differences in regional climate characteristics between present day and global warming of 1.5°C, and between 1.5°C and 2°C. These differences include increases in: mean temperature in most land and ocean regions, hot extremes in most inhabited regions, heavy precipitation in several regions, and the probability of drought and precipitation deficits in some regions.
Evidence from attributed changes in some climate and weather extremes for a global warming of about 0.5°C supports the assessment that an additional 0.5°C of warming compared to present is associated with further detectable changes in these extremes. Several regional changes in climate are assessed to occur with global warming up to 1.5°C compared to pre industrial levels, including warming of extreme temperatures in many regions, increases in frequency, intensity, and/or amount of heavy precipitation in several regions, and an increase in intensity or frequency of droughts in some regions.
Temperature extremes on land are projected to warm more than GMST: extreme hot days in mid latitudes warm by up to about 3°C at global warming of 1.5°C and about 4°C at 2°C, and extreme cold nights in high latitudes warm by up to about 4.5°C at 1.5°C and about 6°C at 2°C. The number of hot days is projected to increase in most land regions, with highest increases in the tropics.
Risks from droughts and precipitation deficits are projected to be higher at 2°C compared to 1.5°C of global warming in some regions. Risks from heavy precipitation events are projected to be higher at 2°C compared to 1.5°C of global warming in several northern hemisphere, high latitude and/or high-elevation regions, eastern Asia and eastern North America. Heavy precipitation associated with tropical cyclones is projected to be higher at 2°C compared to 1.5°C global warming. There is generally low confidence in projected changes in heavy precipitation at 2°C compared to 1.5°C in other regions. Heavy precipitation when aggregated at global scale is projected to be higher at 2°C than at 1.5°C of global warming. As a consequence of heavy precipitation, the fraction of the global land area affected by flood hazards is projected to be larger at 2°C compared to 1.5°C of global warming.
By 2100, global mean sea level rise is projected to be around 0.1 metre lower with global warming of 1.5°C compared to 2°C. Sea level will continue to rise well beyond 2100, and the magnitude and rate of this rise depend on future emission pathways. A slower rate of sea level rise enables greater opportunities for adaptation in the human and ecological systems of small islands, low lying coastal areas and deltas.
Model based projections of global mean sea level rise (relative to 1986-2005) suggest an indicative range of 0.26 to 0.77m by 2100 for 1.5°C of global warming, 0.1m (0.04-0.16m) less than for a global warming of 2°C. A reduction of 0.1m in global sea level rise implies that up to 10 million fewer people would be exposed to related risks, based on population in the year 2010 and assuming no adaptation.
Sea level rise will continue beyond 2100 even if global warming is limited to 1.5°C in the 21st century. Marine ice sheet instability in Antarctica and/or irreversible loss of the Greenland ice sheet could result in multi metre rise in sea level over hundreds to thousands of years. These instabilities could be triggered at around 1.5°C to 2°C of global warming.
Increasing warming amplifies the exposure of small islands, low-lying coastal areas and deltas to the risks associated with sea level rise for many human and ecological systems, including increased saltwater intrusion, flooding and damage to infrastructure. Risks associated with sea level rise are higher at 2°C compared to 1.5°C. The slower rate of sea level rise at global warming of 1.5°C reduces these risks, enabling greater opportunities for adaptation including managing and restoring natural coastal ecosystems and infrastructure reinforcement.
On land, impacts on biodiversity and ecosystems, including species loss and extinction, are projected to be lower at 1.5°C of global warming compared to 2°C. Limiting global warming to 1.5°C compared to 2°C is projected to lower the impacts on terrestrial, freshwater and coastal ecosystems and to retain more of their services to humans.
Of 105,000 species studied, 6% of insects, 8% of plants and 4% of vertebrates are projected to lose over half of their climatically determined geographic range for global warming of 1.5°C, compared with 18% of insects, 16% of plants and 8% of vertebrates for global warming of 2°C. Impacts associated with other biodiversity related risks such as forest fires and the spread of invasive species are lower at 1.5°C compared to 2°C of global warming.
Approximately 4% (interquartile range 2-7%) of the global terrestrial land area is projected to undergo a transformation of ecosystems from one type to another at 1°C of global warming, compared with 13% (interquartile range 8-20%) at 2°C. This indicates that the area at risk is projected to be approximately 50% lower at 1.5°C compared to 2°C.
High latitude tundra and boreal forests are particularly at risk of climate change-induced degradation and loss, with woody shrubs already encroaching into the tundra and this will proceed with further warming. Limiting global warming to 1.5°C rather than 2°C is projected to prevent the thawing over centuries of a permafrost area in the range of 1.5 to 2.5 million km2.
Limiting global warming to 1.5°C compared to 2°C is projected to reduce increases in ocean temperature as well as associated increases in ocean acidity and decreases in ocean oxygen levels. Consequently, limiting global warming to 1.5°C is projected to reduce risks to marine biodiversity, fisheries, and ecosystems, and their functions and services to humans, as illustrated by recent changes to Arctic sea ice and warm water coral reef ecosystems.
There is high confidence that the probability of a sea ice-free Arctic Ocean during summer is substantially lower at global warming of 1.5°C when compared to 2°C. With 1.5°C of global warming, one sea ice free Arctic summer is projected per century. This likelihood is increased to at least one per decade with 2°C global warming. Effects of a temperature overshoot are reversible for Arctic sea ice cover on decadal time scales.
Global warming of 1.5°C is projected to shift the ranges of many marine species to higher latitudes as well as increase the amount of damage to many ecosystems. It is also expected to drive the loss of coastal resources and reduce the productivity of fisheries and aquaculture (especially at low latitudes). The risks of climate induced impacts are projected to be higher at 2°C than those at global warming of 1.5°C. Coral reefs, for example, are projected to decline by a further 70-90% at 1.5°C with larger losses (>99%) at 2°C. The risk of irreversible loss of many marine and coastal ecosystems increases with global warming, especially at 2°C or more.
The level of ocean acidification due to increasing CO2 concentrations associated with global warming of 1.5°C is projected to amplify the adverse effects of warming, and even further at 2°C, impacting the growth, development, calcification, survival, and thus abundance of a broad range of species, for example, from algae to fish.
Impacts of climate change in the ocean are increasing risks to fisheries and aquaculture via impacts on the physiology, survivorship, habitat, reproduction, disease incidence, and risk of invasive species, but are projected to be less at 1.5°C of global warming than at 2°C. One global fishery model, for example, projected a decrease in global annual catch for marine fisheries of about 1.5 million tonnes for 1.5°C of global warming compared to a loss of more than 3 million tonnes for 2°C of global warming.
Climate-related risks to health, livelihoods, food security, water supply, human security, and economic growth are projected to increase with global warming of 1.5°C and increase further with 2°C.
Populations at disproportionately higher risk of adverse consequences with global warming of 1.5°C and beyond include disadvantaged and vulnerable populations, some indigenous peoples, and local communities dependent on agricultural or coastal livelihoods. Regions at disproportionately higher risk indude Arctic ecosystems, dryland regions, small island developing states, and Least Developed Countries. Poverty and disadvantage are expected to increase in some populations as global warming increases; limiting global warming to 1.5°C, compared with 2°C, could reduce the number of people both exposed to climate related risks and susceptible to poverty by up to several hundred million by 2050.
Any increase in global warming is projected to affect human health, with primarily negative consequences. Lower risks are projected at 1.5°C than at 2°C for heat related morbidity and mortality and for ozone related mortality if emissions needed for ozone formation remain high. Urban heat islands often amplify the impacts of heatwaves in cities. Risks from some vector-borne diseases, such as malaria and dengue fever, are projected to increase with warming from 1.5°C to 2°C, including potential shifts in their geographic range.
Limiting warming to 1.5°C compared with 2°C is projected to result in smaller net reductions in yields of maize, rice, wheat, and potentially other cereal crops, particularly in sub-Saharan Africa, Southeast Asia, and Central and South America, and in the CO2-dependent nutritional quality of rice and wheat. Reductions in projected food availability are larger at 2°C than at 1.5°C of global warming in the Sahel, southern Africa, the Mediterranean, central Europe, and the Amazon. Livestock are projected to be adversely affected with rising temperatures, depending on the extent of changes in feed quality, spread of diseases, and water resource availability.
Depending on future socio-economic conditions, limiting global warming to 1.5°C compared to 2°C may reduce the proportion of the world population exposed to a climate change-induced increase in water stress by up to 50%, although there is considerable variability between regions. Many small island developing states could experience lower water stress as a result of projected changes in aridity when global warming is limited to 1.5°C, as compared to 2°C.
Risks to global aggregated economic growth due to climate change impacts are projected to be lower at 1.5°C than at 2°C by the end of this century. This excludes the costs of mitigation, adaptation investments and the benefits of adaptation. Countries in the tropics and Southern Hemisphere subtropics are projected to experience the largest impacts on economic growth due to ciimate change should global warming increase fiom 1.5°C to 2°C.
Exposure to multiple and compound climate-related risks increases between 1.5°C and 2°C of global warming, with greater proportions of people both so exposed and susceptible to poverty in Africa and Asia. For global warming from 1.5°C to 2°C, risks across energy, food, and water sectors could overlap spatially and temporally, creating new and exacerbating current hazards, exposures, and vulnerabilities that could affect increasing numbers of people and regions.
There are multiple lines of evidence that since ARS the assessed levels of risk increased for four of the five Reasons for Concern (RFCs) for global warming to 2°C. The risk transitions by degrees of global warming are now: from high to very high risk between 1.5°C and 2°C for RFC1 (Unique and threatened systems; from moderate to high risk between 1°C and 1.5°C for RFC2 (Extreme weather events); from moderate to high risk between 1.5°C and 2°C for RFC3 (Distribution of impacts; from moderate to high risk between 1.5°C and 2.5°C for RFC4 (Global aggregate impacts); and from moderate to high risk between 1°C and 2.5°C for RFC5 (Large-scale singular events).
Most adaptation needs will be lower for global warming of 1.5°C compared to 2°C. There are a wide range of adaptation options that can reduce the risks of climate change. There are limits to adaptation and adaptive capacity for some human and natural systems at global warming of 1.5°C, with associated losses. The number and availability of adaptation options vary by sector.
A wide range of adaptation options are available to reduce the risks to natural and managed ecosystems (e.g., ecosystem based adaptation, ecosystem restoration and avoided degradation and deforestation, biodiversity management, sustainable aquaculture, and local knowledge and indigenous knowledge). the risks of sea level rise (e.g., coastal defence and hardening), and the risks to health, livelihoods, food, water, and economic growth, especially in rural landscapes (e.g., efficient itrigation, social safety nets, disaster risk management. risk spreading and sharing, and community based adaptation) and urban areas (e.g., green inftastructure, sustainable land use and planning, and sustainable water management).
Adaptation is expected to be more challenging for ecosystems, food and health systems at 2°C of global warming than for 1.5°C. Some vulnerable regions, including small islands and Least Developed Countries, are projected to experience high multiple interrelated climate risks even at global warming of 1.5°C.
Limits to adaptive capacity exist at 1.5°C of global warming, become more pronounced at higher levels of warming and vary by sector, with site specific implications for vulnerable regions, ecosystems and human health.
Figure SPM.2 Five integrative reasons for concern (RFCs) provide a framework for summarizing key impacts and risks across sectors and regions, and were introduced in the IPCC Third Assessment Report. RFCs illustrate the implications of global warming for people, economies and ecosystems. impacts and/or risks for each RFC are based on assessment of the new literature that has appeared. As in ARS, this literature was used to make expert judgments to assess the levels of global warming at which levels of impact and/or risk are undetectable, moderate, high or very high. The selection of impacts and risks to natural, managed and human systems in the lower panel is illustrative and is not intended to be fully comprehensive.
RFC1 Unique and threatened systems: ecological and human systems that have restricted geographic ranges constrained by climate-related conditions and have high endemism or other distinctive properties. Examples include coral reefs, the Arctic: and Its indigenous people, mountain glaciers and biodiversity hotspots.
RFC2 Extreme weather events: risks/impacts to human health, livelihoods, assets and ecosystems from extreme weather events such as heat waves, heavy rain, drought and associated wildfires, and coastal flooding.
RFC3 Distribution of impacts: risks/impacts that disproportionately affect particular groups due to uneven distribution of physical climate change hazards. exposure or vulnerability.
RFC4 Global aggregate impacts: global monetary damage, global-scale degradation and loss of ecosystems and biodiversity.
RFC5 Large-scale singular events: are relatively large, abrupt and somettmes irreversable changes in systems that are caused by global warming. Examples include disintegration of the Greenland and Antarctic Ice sheets.
Emission Pathways and System Transitions Consistent with 1.5°C Global Warming
In model pathways with no or limited overshoot of 1.5°C, global net anthropogenic CO2 emissions decline by about 45% from 2010 levels by 2030 (40-60% interquartile range), reaching net zero around 2050 (2045-2055 interquartile range). For limiting global warming to below 2°C CO2 emissions are projected to decline by about 25% by 2030 in most pathways (10-30% interquartile range) and reach net zero around 2070 (2065-2080 interquartile range). Non CO2 emissions in pathways that limit global warming to 1.5°C show deep reductions that are similar to those in pathways limiting warming to 2°C.
CO2 emissions reductions that limit global warming to 1.5°C with no or limited overshoot can involve different portfolios of mitigation measures. striking different balances between lowering energy and resource intensity, rate of decarbonisation, and the reliance on carbon dioxide removal. Different portfolios face different implementation challenges and potential synergies and trade offs with sustainable development.
Modelled pathways that limit global warming to 1.5°C with no or limited overshoot involve deep reductions in emissions of methane and black carbon (35% or more of both by 2050 relative to 2010). These pathways also reduce most of the cooling aerosols, which partially offsets mitigation effects for two to three decades. Non CO2 emissions can be reduced as a result of broad mitigation measures in the energy sector. In addition, targeted non-C02 mitigation measures can reduce nitrous oxide and methane from agriculture, methane from the waste sector, some sources of black carbon, and hydrofluorocarbons. High bioenergy demand can increase emissions of nitrous oxide in some 1.5°C pathways, highlighting the importance of appropriate management approaches. Improved air quality resulting from projected reductions in many non-CO2 emissions provide direct and immediate population health benefits in all 1.5°C model pathways.
1 GtCO2 = 1 Gigatonne of CO2
1 Gigatonne = 1 Billion tonnes = 1 Trillion kilograms = 1,000,000,000,000 kilograms = 1 million x 1 million kilograms
Limiting global warming requires limiting the total cumulative global anthropogenic emissions of C02 since the pre industrial period, that is, staying within a total carbon budget. By the end of 2017, anthropogenic C02 emissions since the pre industrial period are estimated to have reduced the total carbon budget for 1.5°C by approximately 2200 ± 320 GtCO2. The associated remaining budget is being depleted by current emissions of 42 ± 3 GtCO2 per year. The choice of the measure of global temperature affects the estimated remaining carbon budget. Using global mean surface air temperature, as in ARS, gives an estimate of the remaining carbon budget of 580 GtCO2, for a 50% probability of limiting warming to 1.5°C, and 420 GtCO2 for a 66% probability. Alternatively, using GMST gives estimates of 770 and 570 GtCO2 for 50% and 66% probabilities respectively.
Uncertainties in the size of these estimated remaining carbon budgets are substantial and depend on several factors. Uncertainties in the climate response to C02 and non-CO2 emissions contribute ±400 GtCO2, and the level of historic warming contributes ±250 GtCO2. Potential additional carbon release from future permafrost thawing and methane release from wetlands would reduce budgets by up to 100 GtCO2 over the course of this century and more thereafter. In addition, the level of non-C02 mitigation in the future could alter the remaining carbon budget by 250 GtCO2 in either direction.
Solar radiation modification (SRM) measures are not included in any of the available assessed pathways. Although some SRM measures may be theoretically effective in reducing an overshoot, they face large uncertainties and knowledge gaps, as well as substantial risks and institutional and social constraints to deployment related to governance, ethics, and impacts on sustainable development. They also do not mitigate ocean acidification.
Figure SPM.3a Global emissions pathway characteristics, The main panel shows global net anthropogenic C02 emissions in pathways limiting global warming to 1.5°C, with no or limited (less than 0.1°C) overshoot and pathways wih higher overshoot. The shaded area shows the full range for pathways analysed in this report. The panels on the right show non-CO2 emissions ranges for three compounds with large historical forcing and a substantial portion of emissions coming from sources distinct from those centraI to C02 mitigation. Shaded areas In these panels show the 5-95% (light shading) and interquartile (dark shading) ranges of pathways limiting global warmIng to 1.5°C with no limited overshoot.
Box and whiskers at the bottom of the figure show the timing of pathways reachlng global net zero CO2 emission on levels, and a comparkson with pathways limiting global warmlng to 2°C with at least 66% probability. Four Illustrative model pathways are highlighted in the main panel and are labelled P1, P2, P3 and P4, correspondlng to the LED, S1, S2, and S5 pathways assessed in Chapter 2. Descriptions and characteristics of these pathways are available In Figure SPM3b.
Characteristics of four illustrative model pathways
Different mitigation strategies can achieve the net emissions reductions that would be required to follow a pathway that limits global warming to 1.5°C with no or limited overshoot. All pathways use Carbon Dioxide Removal (CDR), but the amount varies across pathways, as do the relative contributions of Bioenergy with Carbon Capture and Storage (BECCS) and removals in the Agriculture, Forestry and Other Land Use (AFOLU) sector. This has implications for emissions and several other pathway characteristics.
Figure SPM.3b Characteristics of four illustrative model pathways in relation to global warming of 1.5°C introduced in Fgure SPM.3a. These pathways were selected to show a range of potennal mitigation approaches and vary widely in the projected energy and land use, as well as their assumptIons about future socio economlc developments. Including economic and population growth, equity and sustainability. A breakdown of the global net anthropogenic C02 emissions into the contributions in terms of C02 emissions from fossil fuel and industry; agriculture, forestry and other land use (AFOLU); and bioenergy with carbon capture and storage (BECCS) is shown. AFOLU estlmates reported here are not necessarily comparable with countries estimates. Further characteristics for each of these pathways are listed below each pathway, These pathways illustrate relative global differences in mitigation strategies, but do not represent central estimates, national strategies, and do not indicate requirements. For comparison, the rIghi most column shows the interquartile ranges across pathways with no or limited overshoot of 1.5°C. Pathways P1, P2, P3 and P4 correspond to the LED, S1, S2 and S5 pathways assessed In Chapter 2.
Pathways limiting global warming to 1.5°C with no or limited overshoot would require rapid and far reaching transitions in energy, land, urban and infrastructure, including transport and buildings, and industrial systems. These systems transitions are unprecedented in terms of scale, but not necessarily in terms of speed, and imply deep emissions reductions in all sectors, a wide portfolio of mitigation options and a significant upscaling of investments in those options.
Pathways that limit global warming to 1.5°C with no or limited overshoot show system changes that are more rapid and pronounced over the next two decades than in 2°C pathways. The rates of system changes associated with limiting global warming to 1.5°C with no or limited overshoot have occurred in the past within specific sectors, technologies and spatial contexts, but there is no documented historic precedent for their scale.
In energy systems, modelled global pathways (considered in the literature) limiting global warming to 1.5°C with no or limited overshoot (for more details see Figure SPM.3b) generally meet energy service demand with lower energy use, including through enhanced energy efficiency, and show faster electrification of energy end use compared to 2°C. In 1.5°C pathways with no or limited overshoot, low emission energy sources are projected to have a higher share, compared with 2°C pathways, particularly before 2050. In 1.5°C pathways with no or limited overshoot, renewables are projected to supply 70-85% (interquartile range) of electritity in 2050. In electricity generation, shares of nuclear and fossil fuels with carbon dioxide capture and storage (CCS) are modelled to increase in most 1.5“C pathways with no or limited overshoot.
In modelled 1.5°C pathways with limited or no overshoot, the use of CCS would allow the electricity generation share of gas to be approximately 8% (3-11% interquartile range) of global electricity in 2050, while the use of coal shows a steep reduction in all pathways and would be reduced to close to 0% (0-2% interquartile range) of electricity.
While acknowledging the challenges, and differences between the options and national circumstances, political, economic, social and technical feasibility of solar energy, wind energy and electricity storage technologies have substantially improved over the past few years. These improvements signal a potential system transition in electricity generation.
CO2 emissions from industry in pathways limiting global warming to 1.5°C with no or limited overshoot are projected to be about 65-90% (interquartile range) lower in 2050 relative to 2010, as compared to 50-80% for global warming of 2°C. Such reductions can be achieved through combinations of new and existing technologies and practices, including electrification, hydrogen, sustainable bio-based feedstocks. product substitution, and carbon capture utilization and storage (CCUS). These options are technically proven at various scales but their large scale deployment may be limited by economic, financial, human capacity and institutional constraints in specific contexts, and specific characteristics of large-scale industrial installations. In industry, emissions reductions by energy and process efficiency by themselves are insufficient for limiting warming to 1.5°C with no or limited overshoot.
The urban and infrastructure system transition consistent with limiting global warming to 1.5°C with no or limited overshoot would imply, for example, changes in land and urban planning practices, as well as deeper emissions reductions in transport and buildings compared to pathways that limit global warming below 2°C. Technical measures and practices enabling deep emissions reductions include various energy efficiency options.
In pathways limiting global warming to 1.5°C with no or limited overshoot, the electricity share of energy demand in buildings would be about 55-75% in 2050 compared to 50-70% in 2050 for 2°C global warming. In the transport sector, the share of low emission final energy would rise from less than 5% in 2020 to about 35-65% in 2050 compared to 25-45% for 2°C of global warming. Economic, institutional and socio cultural barriers may inhibit these urban and infrastructure system transitions, depending on national, regional and local circumstances, capabilities and the availability of capital.
Transitions in global and regional land use are found in all pathways limiting global warming to 1.5°C with no or limited overshoot, but their scale depends on the pursued mitigation portfolio. Model pathways that limit global warming to 1.5°C with no or limited overshoot project a 4 million km2 reduction to a 2.5 million km2 increase of non-pasture agricultural land for food and feed crops and a 0.5-11 million km2 reduction of pasture land, to be converted into a 0-6 million km2 increase of agricultural land for energy crops and a 2 million km2 reduction to 9.5 million km2 increase in forests by 2050 relative to 2010. Land-use transitions of similar magnitude can be observed in modelled 2°C pathways.
Such large transitions pose profound challenges for sustainable management of the various demands on land for human settlements, food, livestock feed, fibre, bioenergy, carbon storage, biodiversity and other ecosystem services.
Mitigation options limiting the demand for land include sustainable intensification of land-use practices, ecosystem restoration and changes towards less resource intensive diets. The implementation of land based mitigation options would require overcoming socio-economic, institutional, technological, financing and environmental barriers that differ across regions.
Additional annual average energy-related investments for the period 2016 to 2050 in pathways limiting warming to 1.5°C compared to pathways without new climate policies beyond those in place today are estimated to be around 830 billion USD2010 (range of 150 billion to 1700 billion USD2010 across six models). This compares to total annual average energy supply investments in 1.5°C pathways of 1460 to 3510 billion USD2010 and total annual average energy demand investments of 640 to 910 billion USD2010 for the period 2016 to 2050. Total energy-related investments increase by about 12% (range of 3% to 24%) in 1.5°C pathways relative to 2°C pathways. Annual investments in low-carbon energy technologies and energy efficiency are upscaled by roughly a factor of six (range of factor of 4 to 10) by 2050 compared to 2015.
Modelled pathways limiting global warming to 1.5°C with no or limited overshoot project a wide range of global average discounted marginal abatement costs over the 21st century. They are roughly 3-4 times higher than in pathways limiting global warming to below 2°C. The economic literature distinguishes marginal abatement costs from total mitigation costs in the economy. The literatute on total mitigation costs of 1.5°C mitigation pathways is limited and was not assessed in this Report. Knowledge gaps remain in the integrated assessment of the economy wide costs and benefits of mitigation in line with pathways limiting warming to 1.5°C.
All pathways that limit global warming to 1.5°C with limited or no overshoot project the use of carbon dioxide removal (CDR) on the order of 100-1000 GtCO2 over the 21st century. CDR would be used to compensate for residual emissions and, in most cases. achieve net negative emissions to return global warming to 1.5°C following a peak. CDR deployment of several hundreds of GtCO2 is subject to multiple feasibility and sustainability constraints. Significant near term emissions reductions and measures to lower energy and land demand can limit CDR deployment to a few hundred GtCO2 without reliance on bioenergy with carbon capture and storage (BECCS).
Existing and potential CDR measures include afforestation and reforestation, land restoration and soil carbon sequestration, BECCS, direct air carbon capture and storage (DACCS), enhanced weathering and ocean alkalinization. These differ widely in terms of maturity, potentials, costs, risks, co-benefits and trade offs. To date, only a few published pathways include CDR measures other than afforestation and BECCS.
In pathways limiting global warming to 1.5°C with limited or no overshoot, BECCS deployment is projected to range from 0-1, 0-8, and 0-16 GtCO2/yr in 2030, 2050, and 2100, respectively, while agriculture, forestry and land-use (AFOLU) related CDR measures are projected to remove 0-5, 1-11, and 1-5 GtCO2/yr in these years. The upper end of these deployment ranges by mid-century exceeds the BECCS potential of up to 5 GtCO2/yr and afforestation potential of up to 3.6 GtCO2/yr assessed based on recent literature. Some pathways avoid BECCS deployment completely through demand side measures and greater reliance on AFOLU-related CDR measures. The use of bioenergy can be as high or even higher when BECCS is excluded compared to when it is included due to its potential for replacing fossil fuels across sectors.
Pathways that overshoot 1.5°C of global warming rely on CDR exceeding residual CO2 emissions later in the century to return to below 1.5°C by 2100, with larger overshoots requiring greater amounts of CDR. Limitations on the speed, scale, and societal acceptability of CDR deployment hence determine the ability to return global warming to below 1.5°C following an overshoot. Carbon cycle and climate system understanding is still limited about the effectiveness of net negative emissions to reduce temperatures after they peak.
Most current and potential CDR measures could have significant impacts on land, energy, water or nutrients if deployed at large scale. Afforestation and bioenergy may compete with other land uses and may have significant impacts on agricultural and food systems, biodiversity, and other ecosystem functions and services. Effective governance is needed to limit such trade offs and ensure permanence of carbon removal in terrestrial, geological and ocean reservoirs. Feasibility and sustainability of CDR use could be enhanced by a portfolio of options deployed at substantial, but lesser scales, rather than a single option at very large scale.
Some AFOLU-related CDR measures such as restoration of natural ecosystems and soil carbon sequestration could provide co-benefits such as improved biodiversity, soil quality, and local food security. If deployed at large scale, they would require governance systems enabling sustainable land management to conserve and protect land carbon stocks and other ecosystem functions and services.
Strengthening the Global Response in the Context of Sustainable Development and Efforts to Eradicate Poverty
Estimates of the global emissions outcome of current nationally stated mitigation ambitions as submitted under the Paris Agreement would lead to global greenhouse gas emissions in 2030 of 52-58 GtCO2eq yr. Pathways reflecting these ambitions would not limit global warming to 1.5°C, even if supplemented by very challenging increases in the scale and ambition of emissions reductions after 2030. Avoiding overshoot and reliance on future large scale deployment of carbon dioxide removal (CDR) can only be achieved if global CO2 emissions start to decline well before 2030.
Pathways that limit global warming to 1.5°C with no or limited overshoot show clear emission reductions by 2030. All but one show a decline in global greenhouse gas emissions to below 35 GtCO2eq yr in 2030, and half of available pathways fall within the 25-30 GtCO2eq yr range (interquartile range), a 40-50% reduction from 2010 levels.
Pathways reflecting current nationally stated mitigation ambition until 2030 are broadly consistent with cost-effective pathways that result in a global warming of about 3°C by 2100, with warming continuing afterwards.
Overshoot trajectories result in higher impacts and associated challenges compared to pathways that limit global warming to 1.5°C with no or limited overshoot. Reversing warming after an overshoot of 0.2°C or larger during this century would require upscaling and deployment of CDR at rates and volumes that might not be achievable given considerable implementation challenge.
The lower the emissions in 2030, the lower the challenge in limiting global warming to 1.5°C after 2030 with no or limited overshoot. The challenges from delayed actions to reduce greenhouse gas emissions include the risk of cost escalation, lock-in in carbon-emitting infrastructure, stranded assets, and reduced flexibility in future response options in the medium to long term. These may increase uneven distributional impacts between countries at different stages of development.
The avoided climate change impacts on sustainable development, eradication of poverty and reducing inequalities would be greater if global warming were limited to 1.5°C rather than 2°C, if mitigation and adaptation synergies are maximized while trade offs are minimized.
Climate change impacts and responses are closely linked to sustainable development which balances social well-being, economic prosperity and environmental protection.The United Nations Sustainable Development Goals (SDGs), adopted in 2015, provide an established framework for assessing the links between global warming of 1.5°C or 2°C and development goals that include poverty eradication, reducing inequalities, and climate action.
The consideration of ethics and equity can help address the uneven distribution of adverse impacts associated with 1.5°C and higher levels of global warming, as well as those from mitigation and adaptation, particularly for poor and disadvantaged populations, in all societies.
Mitigation and adaptation consistent with limiting global warming to 1.5°C are underpinned by enabling conditions, assessed in this report across the geophysical, environmental, ecological, technological, economic, socio cultural and institutional dimensions of feasibility. Strengthened multilevel governance, institutional capacity, policy instruments, technological innovation and transfer and mobilization of finance, and changes in human behaviour and lifestyles are enabling conditions that enhance the feasibility of mitigation and adaptation options or 1.5°C-consistent systems transitions.
Adaptation options specific to national contexts, if carefully selected, together with enabling conditions, will have benefits for sustainable development and poverty reduction with global warming of 1.5°C, although trade-offs are possible.
Adaptation options that reduce the vulnerability of human and natural systems have many synergies with sustainable development, if well managed, such as ensuring food and water security, reducing disaster risks, improving health conditions, maintaining ecosystem services and reducing poverty and inequality. Increasing investment in physical and social infrastructure is a key enabling condition to enhance the resilience and the adaptive capacities of societies. These benefits can occur in most regions with adaptation to 1.5°C of global warming.
Adaptation to 1.5°C global warming can also result in trade-offs or maladaptations with adverse impacts for sustainable development. For example, if poorly designed or implemented adaptation projects in a range of sectors can increase greenhouse gas emissions and water use, increase gender and social inequality, undermine health conditions, and encroach on natural ecosystems. These trade-offs can be reduced by adaptations that include attention to poverty and sustainable development.
A mix of adaptation and mitigation options to limit global warming to 1.5°C, implemented in a participatory and integrated manner, can enable rapid, systemic transitions in urban and rural areas. These are most effective when aligned with economic and sustainable development, and when local and regional governments and decision makers are supported by national governments.
Adaptation options that also mitigate emissions can provide synergies and cost savings in most sectors and system transitions, such as when land management reduces emissions and disaster risk, or when low-carbon buildings are also designed for efficient cooling. Trade-offs between mitigation and adaptation, when limiting global warming to 1.5°C, such as when bioenergy crops, reforestation or afforestation encroach on land needed for agricultural adaptation, can undermine food security, livelihoods, ecosystem functions and services and other aspects of sustainable development.
Mitigation options consistent with 1.5°C pathways are associated with multiple synergies and trade offs across the Sustainable Development Goals (SDGs). While the total number of possible synergies exceeds the number of trade-offs, their net effect will depend on the pace and magnitude of changes, the composition of the mitigation portfolio and the management of the transition.
1.5°C pathways have robust synergies particularly for the SDGs 3 (health), 7 (clean energy). 11 (cities and communities), 12 (responsible consumption and production) and 14 (oceans). Some 1.5°C pathways show potential trade-offs with mitigation for SDGs 1 (poverty), 2 (hunger), 6 (water) and 7 (energy access), if not managed carefully.
1.5°C pathways that include low energy demand, low material consumption, and low GHG-intensive food consumption have the most pronounced synergies and the lowest number of trade-offs with respect to sustainable development and the SDGs. Such pathways would reduce dependence on CDR. In modelled pathways, sustainable development, eradicating poverty and reducing inequality can support limiting warming to 1.5°C.
Indicative linkages between mitigation options and sustainable development using SDGs
(The linkages do not show costs and benefits)
Mitigation options deployed in each sector can be associated with potential positive effects (synergies) or negative effects (trade-offs) with the Sustainable Development Goals (SDGs). The degree to which this potential is realized will depend on the selected portfolio of mitigation options, mitigation policy design, and local circumstances and context. Particularly in the energy demand sector, the potential for synergies is larger than for trade-offs. The bars group individually assessed options by level of confidence and take into account the relative strength of the assessed mitigation SDG connections.
Figure SPM4 Potential synergies and trad-Offs between the sectoral portfolio of climate change mitigation options and the Sustainable Development Goals (SDGs). The SDGs serve as an analytlcal framework for the assessment of the different sustainable development dimensions, WhIic extend beyond the time frame of the 2030 SDG targets. The assessment is based on literature on mitigation options that are considered relevant fot 1.5°C.
The assessed strength of the SDG interactions id based on the qualitative and quantitative assessment of individual mitigation uptions listed in Table 5.1. For each mitigation option, the strength of the SDG connection as well as the associated confidence of the under lying literature (shades of green and red) was assessed, The strength of positive connections (synergies) and negative connections (trade-offs) across all individual options within a sector (see Table 5.2) are aggregated into sectoral potentials for the whole mitigation portfolio. The white areas outside the bars, which indicate no interactlons, have low confidence due to the untertainty and limited number of studies exploring more direct effects. The strength of the connection consnders only the effect on mitigation and does not include benefits of avoided impacts. SDG 13 (climate action) is not listed because mitigation is being considered in terms of Interactions with SDGs and not vice versa. The bars denote the strength of the connection, and do not consider the strength of the impact on the SDGs. The energy demand sector comprises behavioural responses, fuel swiching and efficiency options in the transport industry and building sector as well as carbon capture options in the industry sector. Options assessed in the energy supply sector comprise biomass and non-biomass renewables, nuclear, carbon capture and storage (CCS) with bioenergy, and CCS with fossil fuels. Options in the land sector comprise agricultural and forest options, sustainable diets and reduced food waste, soil sequestration, livestock and manure management, reduced detorestation, afforestation and reforestation, and responstble sourcing. In addition to this figure, options in the ocean sector are discussed in the underlying report.
Informatton about the net impacts of mitigation on sustainable development in 1.5°C pathways is available only for a limited number of SDGs and mitigation options. Only a limited number of studies have assessed the benefits of avoided climate change impacts of 1.5°C pathways for the SDG, and the co-effects of adaptation for mitigation and the SDGs. The assessment of the indicative mitigation potentials In Figure SPM4 is a step further from ARS towards a more comprehenstve and integrated assessment in the future.
1.5°C and 2°C modelled pathways often rely on the deployment of large-scale land-related measures like afforestation and bioenergy supply, which, if poorly managed, can compete with food production and hence raise food security concerns. The impacts of carbon dioxide removal (CDR) options on SDGs depend on the type of options and the scale of deployment. If poorly implemented, CDR options such as BECCS and AFOLU options would lead to trade-offs. Context-relevant design and implementation requires considering people’s needs, biodiversity, and other sustainable development dimensions.
Mitigation consistent with 1.5°C pathways creates risks for sustainable development in regions with high dependency on fossil fuels for revenue and employment generation. Policies that promote diversification of the economy and the energy sector can address the associated challenges.
Redistributive policies across sectors and populations that shield the poor and vulnerable can resolve trade-offs for a range of SDGs, particularly hunger, poverty and energy access. Investment needs for such complementary policies are only a small fraction of the overall mitigation investments in 1.5°C pathways.
Limiting the risks from global warming of 1.5°C in the context of sustainable development and poverty eradication implies system transitions that can be enabled by an increase of adaptation and mitigation investments, policy instruments, the acceleration of technological innovation and behaviour changes.
Directing finance towards investment in infrastructure for mitigation and adaptation could provide additional resources. This could involve the mobilization of private funds by institutional investors, asset managers and development or investment banks, as well as the provision of public funds. Government policies that lower the risk of low-emission and adaptation investments can facilitate the mobilization of private funds and enhance the effectiveness of other public policies. Studies indicate a number of challenges, including access to finance and mobilization of funds.
Adaptation finance consistent with global warming of 1.5°C is difficult to quantify and compare with 2°C. Knowledge gaps include insufficient data to calculate specific climate resilience-enhancing investments from the provision of currently underinvested basic infrastructure. Estimates of the costs of adaptation might be lower at global warming of 1.5°C than for 2°C. Adaptation needs have typically been supported by public sector sources such as national and subnational government budgets, and in developing countries together with support from development assistance, multilateral development banks, and United Nations Framework Convention on Climate Change channels.
More recently there is a growing understanding of the scale and increase in non-govemmental organizations and private funding in some regions. Barriers include the scale of adaptation financing, limited capacity and access to adaptation finance.
Global model pathways limiting global warming to 1.5°C are projected to involve the annual average investment needs in the energy system of around 2.4 trillion USD2010 between 2016 and 2035, representing about 2.5% of the world GDP.
Policy tools can help mobilize incremental resources, including through shifting global investments and savings and through market and non-market based instruments as well as accompanying measures to secure the equity of the transition. Acknowledging the challenges related with implementation, including those of energy costs, depreciation of assets and impacts on international competition, and milizing the opportunities to maximize co-benefits.
The systems transitions consistent with adapting to and limiting global warming to 1.5°C include the widespread adoption of new and possibly disruptive technologies and practices and enhanced climate-driven innovation. These imply enhanced technological innovation capabilities, including in industry and finance. Both national innovation policies and international cooperation can contribute to the development, commercialization and widespread adoption of mitigation and adaptation technologies. Innovation policies may be more effective when they combine public support for research and development with policy mixes that provide incentives for technology diffusion.
Education, information, and community approaches, including those that are informed by indigenous knowledge and local knowledge, can accelerate the wide scale behaviour changes consistent with adapting to and limiting global warming to 1.5°C. These approaches are more effective when combined with other policies and tailored to the motivations, capabilities and resources of specific actors and contexts. Public acceptability can enable or inhibit the implementation of policies and measures to limit global warming to 1.5°C and to adapt to the consequences. Public acceptability depends on the individual’s evaluation of expected policy consequences, the perceived fairness of the distribution of these consequences. and perceived fairness of decision procedures.
Sustainable development supports, and often enables, the fundamental societal and systems transitions and transformations that help limit global warming to 1.5°C. Such changes facilitate the pursuit of climate resilient development pathways that achieve ambitious mitigation and adaptation in conjunction with poverty eradication and efforts to reduce inequalities.
Social justice and equity are core aspects of climate-resilient development pathways that aim to limit global warming to 1.5°C as they address challenges and inevitable trade offs, widen opportunities, and ensure that options, visions, and values are deliberated, between and within countries and communities, without making the poor and disadvantaged worse off.
The potential for climate-resilient development pathways differs between and within regions and nations, due to different development contexts and systemic vulnerabilities. Efforts along such pathways to date have been limited and enhanced efforts would involve strengthened and timely action from all countries and non-state actors.
Pathways that are consistent with sustainable development show fewer mitigation and adaptation challenges and are associated with lower mitigation costs. The large majority of modelling studies could not construct pathways characterized by lack of international cooperation, inequality and poverty that were able to limit global warming to 1.5°C.
Strengthening the capacities for climate action of national and sub national authorities, civil society, the private sector, indigenous peoples and local communities can support the implementation of ambitious actions implied by limiting global warming to 1.5°C. International cooperation can provide an enabling environment for this to be achieved in all countries and for all people, in the context of sustainable development. International cooperation is a critical enabler for developing countries and vulnerable regions.
Partnerships involving non-state public and private actors, institutional investors, the banking system, civil society and scientific institutions would facilitate actions and responses consistent with limiting global warming to 1.5°C.
Cooperation on strengthened accountable multilevel governance that includes non-state actors such as industry, civil society and scientific institutions, coordinated sectoral and cross-sectoral policies at various governance levels, gender sensitive policies, finance including innovative financing. and cooperation on technology development and transfer can ensure participation, transparency, capacity building and learning among different players.
International cooperation is a critical enabler for developing countries and vulnerable regions to strengthen their action for the implementation of 1.5°C consistent climate responses, including through enhancing access to finance and technology and enhancing domestic capacities, taking into account national and local circumstances and needs.
Collective efforts at all levels, in ways that reflect different circumstances and capabilities, in the pursuit of limiting global warming to 1.5°C, taking into account equity as well as effectiveness, can facilitate strengthening the global response to climate change, achieving sustainable development and eradicating poverty.