A mix of mitigation and adaptation options implemented in a participatory and integrated manner can enable rapid, systemic transitions – in urban and rural areas – that are necessary elements of an accelerated transition consistent with limiting warming to 1.5°C. Such options and changes are most effective when aligned with economic and sustainable development, and when local and regional governments are supported by national governments {4.3.3, 4.4.1, 4.4.3}. Various mitigation options are expanding rapidly across many geographies. Although many have development synergies, not all income groups have so far benefited from them. Electrification, end-use energy efficiency and increased share of renewables, amongst other options, are lowering energy use and decarbonizing energy supply in the built environment, especially in buildings. Other rapid changes needed in urban environments include demotorization and decarbonization of transport, including the expansion of electric vehicles, and greater use of energy-efficient appliances ( medium evidence, high agreement). Technological and social innovations can contribute to limiting warming to 1.5°C, for example, by enabling the use of smart grids, energy storage technologies and general-purpose technologies, such as information and communication technology (ICT) that can be deployed to help reduce emissions. Feasible adaptation options include green infrastructure, resilient water and urban ecosystem services, urban and peri-urban agriculture, and adapting buildings and land use through regulation and planning ( medium evidence, medium to high agreement). {4.3.3, 4.4.3, 4.4.4} Under emissions in line with current pledges under the Paris Agreement (known as Nationally Determined Contributions, or NDCs), global warming is expected to surpass 1.5°C above pre-industrial levels, even if these pledges are supplemented with very challenging increases in the scale and ambition of mitigation after 2030 ( high confidence). This increased action would need to achieve net zero CO 2 emissions in less than 15 years. Even if this is achieved, temperatures would only be expected to remain below the 1.5°C threshold if the actual geophysical response ends up being towards the low end of the currently estimated uncertainty range. Transition challenges as well as identified trade-offs can be reduced if global emissions peak before 2030 and marked emissions reductions compared to today are already achieved by 2030 {2.2, 2.3.5, Cross-Chapter Box 11 in Chapter 4}. Current ecosystem services from the ocean are expected to be reduced at 1.5°C of global warming, with losses being even greater at 2°C of global warming ( high confidence). The risks of declining ocean productivity, shifts of species to higher latitudes, damage to ecosystems (e.g., coral reefs, and mangroves, seagrass and other wetland ecosystems), loss of fisheries productivity (at low latitudes), and changes to ocean chemistry (e.g., acidification, hypoxia and dead zones) are projected to be substantially lower when global warming is limited to 1.5°C ( high confidence). {3.4.4, Box 3.4} When multiplying decimals, say, 0.2 0.2 0.2 and 1.25 1.25 1.25, we can begin by forgetting the dots. That means that to find 0.2 × 1.25 0.2 \times 1.25 0.2 × 1.25, we start by finding 2 × 125 2 \times 125 2 × 125, which is 250 250 250. Then we count how many digits to the right of the dots we had in total in the numbers we started with (in this case, it's three: one in 0.2 0.2 0.2 and two in 1.25 1.25 1.25). We then write the dot that many digits from the right in what we obtained. For us, this translates to putting the dot to the left of 2 2 2, which gives 0.250 = 0.25 0.250 = 0.25 0.250 = 0.25 (we write 0 0 0 if we have no number in front of the dot).

The impacts of large-scale CDR deployment could be greatly reduced if a wider portfolio of CDR options were deployed, if a holistic policy for sustainable land management were adopted, and if increased mitigation efforts were employed to strongly limit the demand for land, energy and material resources, including through lifestyle and dietary changes ( medium confidence). In particular, reforestation could be associated with significant co-benefits if implemented in a manner than helps restore natural ecosystems ( high confidence). {Cross-Chapter Box 7 in this chapter} This chapter takes sustainable development as the starting point and focus for analysis. It considers the broad and multifaceted bi-directional interplay between sustainable development, including its focus on eradicating poverty and reducing inequality in their multidimensional aspects, and climate actions in a 1.5°C warmer world. These fundamental connections are embedded in the Sustainable Development Goals (SDGs). The chapter also examines synergies and trade-offs of adaptation and mitigation options with sustainable development and the SDGs and offers insights into possible pathways, especially climate-resilient development pathways towards a 1.5°C warmer world. Limiting warming to 1.5°C implies reaching net zero CO 2 emissions globally around 2050 and concurrent deep reductions in emissions of non- CO 2 forcers, particularly methane ( high confidence). Such mitigation pathways are characterized by energy-demand reductions, decarbonization of electricity and other fuels, electrification of energy end use, deep reductions in agricultural emissions, and some form of CDR with carbon storage on land or sequestration in geological reservoirs. Low energy demand and low demand for land- and GHG-intensive consumption goods facilitate limiting warming to as close as possible to 1.5°C. {2.2.2, 2.3.1, 2.3.5, 2.5.1, Cross-Chapter Box 9 in Chapter 4}. Adaptation needs will be lower in a 1.5°C world compared to a 2°C world ( high confidence) {Chapter 3; Cross-Chapter Box 11 in this chapter}. Learning from current adaptation practices and strengthening them through adaptive governance {4.4.1}, lifestyle and behavioural change {4.4.3} and innovative financing mechanisms {4.4.5} can help their mainstreaming within sustainable development practices.Preventing maladaptation,drawing on bottom-up approachesIn ‘global aggregate impacts’ (RFC4) a transition from moderate to high levels of risk is now located between 1.5°C and 2 .5°C of global warming, as opposed to at 3.6°C of warming in AR5, owing to new evidence about global aggregate economic impacts and risks to Earth’s biodiversity ( medium confidence). {3.5} In the unlikely event that we have sent you an incorrect product, as soon as we have been notified, we will arrange a swift collection and organise for the right one to be delivered straight-away.

The probability of a sea-ice-free Arctic Ocean 5 during summer is substantially higher at 2°C compared to 1.5°C of global warming ( medium confidence). Model simulations suggest that at least one sea-ice-free Arctic summer is expected every 10 years for global warming of 2°C, with the frequency decreasing to one sea-ice-free Arctic summer every 100 years under 1.5°C ( medium confidence). An intermediate temperature overshoot will have no long- term consequences for Arctic sea ice coverage, and hysteresis is not expected ( high confidence). {3.3.8, 3.4.4.7} Cumulative CO 2 emissions are kept within a budget by reducing global annual CO 2 emissions to net zero. This assessment suggests a remaining budget of about 420 GtCO 2 for a two-thirds chance of limiting warming to 1.5°C, and of about 580 GtCO 2 for an even chance ( medium confidence). The remaining carbon budget is defined here as cumulative CO 2 emissions from the start of 2018 until the time of net zero global emissions for global warming defined as a change in global near-surface air temperatures. Remaining budgets applicable to 2100 would be approximately 100 GtCO 2 lower than this to account for permafrost thawing and potential methane release from wetlands in the future, and more thereafter. These estimates come with an additional geophysical uncertainty of at least ±400 GtCO 2, related to non-CO 2 response and TCRE distribution. Uncertainties in the level of historic warming contribute ±250 GtCO 2. In addition, these estimates can vary by ±250 GtCO 2 depending on non-CO 2 mitigation strategies as found in available pathways. {2.2.2, 2.6.1}

The ocean has absorbed about 30% of the anthropogenic carbon dioxide, resulting in ocean acidification and changes to carbonate chemistry that are unprecedented for at least the last 65 million years ( high confidence). Risks have been identified for the survival, calcification, growth, development and abundance of a broad range of marine taxonomic groups, ranging from algae to fish, with substantial evidence of predictable trait-based sensitivities ( high confidence). There are multiple lines of evidence that ocean warming and acidification corresponding to 1.5°C of global warming would impact a wide range of marine organisms and ecosystems, as well as sectors such as aquaculture and fisheries ( high confidence). {3.3.10, 3.4.4}

Small islands are projected to experience multiple inter- related risks at 1.5°C of global warming that will increase with warming of 2°C and higher levels ( high confidence). Climate hazards at 1.5°C are projected to be lower compared to those at 2°C ( high confidence). Long-term risks of coastal flooding and impacts on populations, infrastructures and assets ( high confidence), freshwater stress ( medium confidence), and risks across marine ecosystems ( high confidence) and critical sectors ( medium confidence) are projected to increase at 1.5°C compared to present-day levels and increase further at 2°C, limiting adaptation opportunities and increasing loss and damage ( medium confidence). Migration in small islands (internally and internationally) occurs for multiple reasons and purposes, mostly for better livelihood opportunities ( high confidence) and increasingly owing to sea level rise ( medium confidence). {3.3.2.2, 3.3.6–9, 3.4.3.2, 3.4.4.2, 3.4.4.5, 3.4.4.12, 3.4.5.3, 3.4.7.1, 3.4.9.1, 3.5.4.9, Box 3.4, Box 3.5} Policies reflecting a high price on emissions are necessary in models to achieve cost-effective 1.5°C pathways ( high confidence). Other things being equal, modelling studies suggest the global average discounted marginal abatement costs for limiting warming to 1.5°C being about 3–4 times higher compared to 2°C over the 21st century, with large variations across models and socio-economic and policy assumptions. Carbon pricing can be imposed directly or implicitly by regulatory policies. Policy instruments, like technology policies or performance standards, can complement explicit carbon pricing in specific areas. {2.5.1, 2.5.2, 4.4.5} This chapter assesses mitigation pathways consistent with limiting warming to 1.5°C above pre-industrial levels. In doing so, it explores the following key questions: What role do CO 2 and non-CO 2 emissions play? {2.2, 2.3, 2.4, 2.6} To what extent do 1.5°C pathways involve overshooting and returning below 1.5°C during the 21st century? {2.2, 2.3} What are the implications for transitions in energy, land use and sustainable development? {2.3, 2.4, 2.5} How do policy frameworks affect the ability to limit warming to 1.5°C? {2.3, 2.5} What are the associated knowledge gaps? {2.6} Our custom cutting services ensure you get the size you need at the highest quality. With ongoing investment into our plant and machinery combined with regular maintenance and calibration, we aim for consistency and exceptional results. We offer a range of services using the right equipment and skilled metal workers.

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Pursuing place-specific adaptation pathways towards a 1.5°C warmer world has the potential for significant positive outcomes for well-being in countries at all levels of development ( medium evidence, high agreement). Positive outcomes emerge when adaptation pathways (i) ensure a diversity of adaptation options based on people’s values and the trade-offs they consider acceptable, (ii) maximize synergies with sustainable development through inclusive, participatory and deliberative processes, and (iii) facilitate equitable transformation. Yet such pathways would be difficult to achieve without redistributive measures to overcome path dependencies, uneven power structures, and entrenched social inequalities ( medium evidence, high agreement). {5.3.3} In comparison to a 2°C limit, the transformations required to limit warming to 1.5°C are qualitatively similar but more pronounced and rapid over the next decades ( high confidence). 1.5°C implies very ambitious, internationally cooperative policy environments that transform both supply and demand ( high confidence). {2.3, 2.4, 2.5} Risks of water scarcity are projected to be greater at 2°C than at 1.5°C of global warming in some regions ( medium confidence). 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 ( medium confidence). Regions with particularly large benefits could include the Mediterranean and the Caribbean ( medium confidence). Socio-economic drivers, however, are expected to have a greater influence on these risks than the changes in climate ( medium confidence). {3.3.5, 3.4.2, Box 3.5} 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 ( medium confidence). This assessment is based on several lines of evidence, including attribution studies for changes in extremes since 1950. {3.2, 3.3.1, 3.3.2, 3.3.3, 3.3.4}

Future risks at 1.5°C of global warming will depend on the mitigation pathway and on the possible occurrence of a transient overshoot ( high confidence). The impacts on natural and human systems would be greater if mitigation pathways temporarily overshoot 1.5°C and return to 1.5°C later in the century, as compared to pathways that stabilize at 1.5°C without an overshoot ( high confidence). The size and duration of an overshoot would also affect future impacts (e.g., irreversible loss of some ecosystems) ( high confidence). Changes in land use resulting from mitigation choices could have impacts on food production and ecosystem diversity. {3.6.1, 3.6.2, Cross-Chapter Boxes 7 and 8 in this chapter}

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CDR deployed at scale is unproven, and reliance on such technology is a major risk in the ability to limit warming to 1.5°C. CDR is needed less in pathways with particularly strong emphasis on energy efficiency and low demand. The scale and type of CDR deployment varies widely across 1.5°C pathways, with different consequences for achieving sustainable development objectives ( high confidence). Some pathways rely more on bioenergy with carbon capture and storage (BECCS), while others rely more on afforestation, which are the two CDR methods most often included in integrated pathways. Trade-offs with other sustainability objectives occur predominantly through increased land, energy, water and investment demand. Bioenergy use is substantial in 1.5°C pathways with or without BECCS due to its multiple roles in decarbonizing energy use. {2.3.1, 2.5.3, 2.6.3, 4.3.7} C emission pathways are defined as those that, given current knowledge of the climate response, provide a one- in-two to two-in-three chance of warming either remaining below 1.5°C or returning to 1.5°C by around 2100 following an overshoot. Overshoot pathways are characterized by the peak magnitude of the overshoot, which may have implications for impacts. All 1.5°C pathways involve limiting cumulative emissions of long-lived greenhouse gases, including carbon dioxide and nitrous oxide, and substantial reductions in other climate forcers ( high confidence). Limiting cumulative emissions requires either reducing net global emissions of long-lived greenhouse gases to zero before the cumulative limit is reached, or net negative global emissions (anthropogenic removals) after the limit is exceeded. {1.2.3, 1.2.4, Cross-Chapter Boxes 1 and 2} The energy system transition that would be required to limit global warming to 1.5°C above pre-industrial conditions is underway in many sectors and regions around the world ( medium evidence, high agreement). The political, economic, social and technical feasibility of solar energy, wind energy and electricity storage technologies has improved dramatically over the past few years, while that of nuclear energy and carbon dioxide capture and storage (CCS) in the electricity sector have not shown similar improvements. {4.3.1} Call 01902 716333 for nationwide delivery of mild steel box section Mild Steel Box Section - Regtangular and Square RHS in cold and hot finish. Mild Steel Rectangular and Square hollow section, also called box section. Can be supplied in various grades including BS EN 10025 S355 and S275.