RESUMEN
Incorporating health cobenefits from coabated air pollution into carbon mitigation policy making is particularly important for developing countries to boost policy efficiency. For sectors that highly depend on electrification for decarbonization, it remains unclear how the increased electricity demand and consequent health impacts from sectoral mitigation policy in one province would change the scale and the regional and sectoral distributions of the overall health impacts in the whole country. This study chooses the banning of new sales of internal combustion engine vehicles in the private vehicle sector in China as a case. The results show that, without carbon neutrality and air pollution control goals in electricity generation, 53% of CO2 reduction and 65% of health benefits from the private vehicle sector would be offset by increased electricity demand. The regional distributions of CO2 reduction and health benefits due to a province-driven ban policy are greatly uneven, as the top five provinces take up over one-third of the total impact in China. Health benefits per ton of carbon reduction (H/C) may vary by up to 8 times across provinces. Finally, the provinces in southeast China and the Sichuan Basin, with their stably high H/C values, are suggested to enact the province-driven ban policy first.
RESUMEN
Projecting mitigations of carbon neutrality from individual countries in relation to future global warming is of great importance for depicting national climate responsibility but is poorly quantified. Here, we show that China's carbon neutrality (CNCN) can individually mitigate global warming by 0.48 °C and 0.40 °C, which account for 14% and 9% of the global warming over the long term under the shared socioeconomic pathway (SSP) 3-7.0 and 5-8.5 scenarios, respectively. Further incorporating changes in CH4 and N2O emissions in association with CNCN together will alleviate global warming by 0.21 °C and 0.32 °C for SSP1-2.6 and SSP2-4.5 over the long term, and even by 0.18 °C for SSP2-4.5 over the mid-term, but no significant impacts are shown for all SSPs in the near term. Divergent responses in alleviated warming are seen at regional scales. The results provide a useful reference for the global stocktake, which assesses the collective progress towards the climate goals of the Paris Agreement.
Asunto(s)
Carbono , Calentamiento Global , Dióxido de Carbono/metabolismo , China , Calentamiento Global/prevención & control , Efecto Invernadero , Modelos TeóricosRESUMEN
The expansion of road networks in emerging economies such as China causes significant greenhouse gas (GHG) emissions. This development is conflicting with China's commitment to achieve carbon neutrality. Thus, there is a need to better understand life cycle emissions of road infrastructure and opportunities to mitigate these emissions. Existing impact studies of roads in developing countries do not address recycled materials, improved pavement maintenance, or pavement-vehicle interaction and electric vehicle (EV) adoption. Combining firsthand information from Chinese road construction engineers with publicly available data, this paper estimates a comprehensive account of GHG emissions of the road pavement network to be constructed in the next ten years in the Shandong province in Northern China. Further, we estimate the potential of GHG emission reductions achievable under three scenario sets: maintenance optimization, alternative pavement material replacement, and EV adoption. Results show that the life cycle GHG emissions of highways and Class 1-4 roads to be constructed in the next 10 years amount to 147 Mt CO2-eq. Considering the use phase in our model reveals that it is the dominant stage in terms of emissions, largely due to pavement-vehicle interaction. Vehicle electrification can only moderately mitigate these emissions. Other stages, such as materials production and road maintenance and rehabilitation, contribute substantially to GHG emissions as well, highlighting the importance of optimizing the management of these stages. Surprisingly, longer, not shorter maintenance intervals, yield significant emission reductions. Another counter-intuitive finding is that thicker and more material-intensive pavement surfaces cause lower emissions overall. Taken together, optimal maintenance and rehabilitation schedules, alternative material use, and vehicle electrification provide GHG reduction potentials of 11%, 4%-16% and 2%-6%, respectively.
Asunto(s)
Gases de Efecto Invernadero , Animales , Carbono , China , Efecto Invernadero , Estadios del Ciclo de Vida , ReciclajeRESUMEN
BACKGROUND: The announcement of China's 2060 carbon neutrality goal has drawn the world's attention to the specific technology pathway needed to achieve this pledge. We aimed to evaluate the health co-benefits of carbon neutrality under different technology pathways, which could help China to achieve the carbon neutrality goal, air quality goal, and Healthy China goal in a synergetic manner that includes health in the decision-making process. METHODS: In this modelling study, we used Shared Socioeconomic Pathway 2 with no climate policy as the reference scenario, and two representative carbon neutrality scenarios with identical emission trajectories and different technology pathways-one was led by renewable energies and the other was led by negative emission technologies. We had three modules to analyse health co-benefits and mitigation costs for each policy scenario. First, we used a computable general equilibrium model that captures the operation of the whole economic system to investigate the carbon mitigation costs and air pollutant emission pathways of different technology portfolios. Second, we used a reduced complexity air quality model to estimate the concentrations of particulate matter in the atmosphere from the air pollutant emission pathways. Finally, we used a health impact evaluation model to estimate premature deaths, morbidity, and the resulting loss of life expectancy, then these health impacts were monetised according to value of a statistical life and cost of illness. We compared the monetised health co-benefits against the corresponding mitigation costs to explore the cost-effectiveness of different technology portfolios. A series of uncertainties embodied in carbon neutrality pathways and models were considered. FINDINGS: In our models, sole dependence on improving end-of-pipe air pollution control measures is not sufficient for all Chinese provinces to meet the 2005 WHO PM2·5 standards (10 µg/m3) by 2060. Only a combination of strong climate and air pollution control policies can lead to substantial improvement of air quality across China. If the carbon neutrality pathway led by developing renewable energies was followed, the air quality of all provinces could meet the WHO guideline by 2060. With the realisation of carbon neutrality goals, the total discounted mitigation costs (discount rate 5%) from 2020-60 would range from 40-125 trillion Chinese yuan (CNY), and 22-50 million cumulative premature deaths could be avoided. China has the potential to increase the associated life expectancy by 0·88-2·80 years per person in 2060 versus the reference scenario. The health benefits are higher in the renewable energies-led scenarios, whereas the mitigation costs are smaller in the negative emission technologies-led scenarios. If the value of a statistical life is set higher than 12·5 million CNY (39% of the Organisation for Economic Co-operation and Development value), the health co-benefits will be higher than mitigation costs, even when considering all included uncertainties, implying the cost-effectiveness of China's carbon neutrality goal. INTERPRETATION: The life expectancy increase from the realisation of China's 2060 carbon neutrality goal could be equivalent to the past 5-10 years of life expectancy growth in China. Choosing an appropriate carbon neutrality pathway affects the health of China's population both today and in the future. Our findings suggest that, if China incorporates health co-benefits into climate policy making and puts a high value on people's health, it should choose a carbon neutrality pathway that relies more on developing renewable energies and avoid over-reliance on negative emission technologies. FUNDING: National Key R&D Program of China, National Natural Science Foundation of China, Tsinghua-Toyota Joint Research Fund, Tsinghua-Rio Tinto Joint Research Centre for Resources, and Global Energy Interconnection Group. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.