Wenjia Cai

Health and climate change: policy responses to protect public health

The 2015 Lancet Commission on Health and Climate Change has been formed to map out the impacts of climate change, and the necessary policy responses, in order to ensure the highest attainable stand ...

The Lancet Countdown on health and climate change: from 25 years of inaction to a global transformation for public health

The Lancet Countdown tracks progress on health and climate change and provides an independent assessment of the health effects of climate change, the implementation of the Paris Agreement, 1 and th ...

Quantifying Baseline Emission Factors of Air Pollutants in China's Regional Power Grids

Drawing lessons from the clean development mechanism (CDM), this paper developed a combined margin methodology to quantify baseline emission factors of air pollutants in Chinas regional power grids. The simple average of baseline emission factors of SO2, NOX, and PM2.5 in Chinas six power grids in 2010 were respectively 1.91 kg/MWh, 1.83 kg/MWh and 0.32 kg/MWh. Several low-efficient mitigation technologies, such as low nitrogen oxide burner (LNB), were suggested to be replaced or used together with other technologies in order to virtually decrease the grids emission factor. The synergies between GHG and air pollution mitigation in Chinas power sector was also notable. It is estimated that in 2010, that every 1% CO2 reduction in Chinas power generation sector resulted in the respective coreduction of 1.1%, 0.5%, and 0.8% of SO2, NOX, and PM2.5. Wind is the best technology to achieve the largest amount of coabatement in most parts of China. This methodology is recommended to be used in making comprehensive air pollution control strategies and in cobenefits analysis in future CDM approval processes.

Policies and Practices of Low Carbon City Development in China

Globally as well as in China, cities have contributed to most of economic output and have accordingly given rise to most of CO2 emissions. In particular, given unprecedented urbanization, cities will play an even greater role in shaping energy demand and CO2 emissions. Therefore, cities are the key to meeting its proposed carbon intensity target in 2020 and whatever climate commitments beyond 2020 that China may take. Given the paramount importance of cities, China is practicing low carbon city (LCC) development. Against this background, this paper first summarizes the general situation and main characteristics of Chinas LCC development. The paper then indentifies eight problems and challenges for Chinas LCC development including the absence of sound carbon accounting systems, lack of low-carbon specific evaluation system, rare use of market-based instruments, insufficient government-enterprise interactions, excessive budget dependence on land concession, increasing difficulty in further carbon mitigation, inevitable emissions growth due to rising living standards, and coal-dominant energy structure in the foreseeable future. Since these challenges are not applied to one or few cities, but are to all cities across the country, finally, the paper discusses how governments, in particular the central government, should address these problems and challenges. Given that China has faced great difficulty ensuring that local governments act in accordance with centrally-directed policies, the paper in particular discusses ways to incentivize local governments not to focus on economic growth alone and to move away from a heavy reliance on land concession. The paper ends with emphasizing on putting a price on carbon a crucial step for Chinas endeavor of harnessing the market forces to reduce its energy consumption and carbon emissions and genuinely transiting into a low-carbon economy.

The Tsinghua–Lancet Commission on Healthy Cities in China: unlocking the power of cities for a healthy China

Executive summary: Over the past four decades, rapid urbanisation in China has brought unprecedented health benefits to its urban population, but has also created new challenges for protection of and promotion of health in cities. With the shift from rural to urban living, more people than ever enjoy the health advantages that cities can provide, such as better access to health services and improved sanitation. For example, the average life expectancy of male urban residents in 2010 was estimated to be 7·09 years longer than that of of their counterparts in rural China; urban females lived 6·64 years longer.1 Other changes associated with rapid urbanisation– including large-scale migration, ageing, pollution, shifts in diet and lifestyle, and social inequality–have created new health challenges.2 For example, about 52% of people over 60 years old lived in urban areas in 2015 compared with 34% in 2000,3 thus increasing the burden of senior care in Chinese cities. Non-communicable diseases have replaced infectious diseases as the leading cause of death among urban residents; the percentage of years of life lost because of such diseases as a fraction of all-cause years of life lost increased from 50·0% (95% CI 48·5–53·0) in 1990 to 77·3% (76·5–78·1) in 2015.4 Health inequality also increased in urban areas.5 China has acted to address urban health challenges by passing strict environmental regulations and investing heavily in urban infrastructure. Major reforms have been passed to increase the transparency of environmental governance to control pollution over the short term, while moving to reform whole industries and thus provide long-term solutions. Programmes like the Hygienic Cities movement have invested heavily in urban infrastructure to promote health, including major improvements in urban sanitation.6 China has also increased coverage of and accessibility to health services in urban areas. In 2016, around 93·8% of the urban population was covered by urban medical insurance programmes, a substantial increase from 4·1% in 1998 when the programmes started.7,8 Meanwhile, cities in China are also testing new strategies for urban health management, such as China’s pilot Healthy Cities project.9 Management of chronic diseases and mental disorders in cities has improved dramatically and major progress has been made regarding access to preventive and primary health services. All these efforts have contributed to the reduction of exposure to health risks and health improvement in urban China. However, despite these successes, major gaps remain, including but not limited to an over-reliance on a top-down-approach to environmental management, a narrow focus on health care in urban health management, and a scarcity of intersectoral action. Given that the urbanisation rate in China is predicted to reach 71% by 2030,10 urban health challenges will continue to emerge and expand. If innovative strategies are not used to address these issues, they will become major obstacles to the achievement of improved health and development for millions of people. It has also become clear that the health sector alone, with its traditional piecemeal approach, cannot effectively resolve the modern challenges to urban health in China. The country is now in a transitional period in which the pursuit of economic growth at any cost is being replaced by sustainable development. In 2013, President Xi Jinping declared China’s intention to develop a so-called ecological civilisation (ecocivilisation), the core principles of which involve balancing the relationship between humanity and nature. During this transition, health is recognised as the centrepiece of sustainable development in China, as highlighted in the Healthy China 2030 plan that was adopted in 2016.11 As a result, people-centred and health-oriented urban development will hopefully prevail in China; however, major efforts, political will, and investments will be needed to put this vision into practice. The Tsinghua–Lancet Commission on Healthy Cities in China aimed to characterise, understand, and address urban health challenges in the unique context of China’s rapid and dynamic urban development. Experts from a wide range of disciplines examined environmental and social determinants of health, identified key stakeholders,and assessed actions for the prevention, management, and control of adverse health outcomes associated with the country’s urban experience. We conclude that key efforts are needed to combat urban health challenges in China and these should be unified with the Healthy Cities movement, which uses a systems approach to urban health management and provides a clear path to the realisation of the Healthy China 2030 plan. Actions taken to build healthy cities in China have contributed to global knowledge on the development of healthy cities in other parts of the world. China’s strategic, simultaneous rollout of diverse trials in different cities— in areas such as health education and promotion—and its rapid adoption of effective approaches at the national scale is a valuable lesson for other countries facing rapid urbanisation. Despite such successes, we believe that there is room for substantial improvement and make the following five key recommendations. Integrate health into all policies China should take advantage of new, human-centred urbanisation strategies. For example, cities should integrate health into urban planning and design as a first step towards the integration of health into all policies. Increase participation Cities should increase participation by residents, the private sector, non-governmental organisations (NGOs), and community groups in health management. This increase can be achieved through investment in community capacity building and engagement with the private sector. Promote intersectoral action To motivate and sustain intersectoral action in the design, building, and management of healthy cities, cities should develop ways to assess the health effects of urban management by use of measures that span multiple and diverse sectors. Set local goals for 2030 and assess progress periodically Cities should view the health goals specified in the Healthy China 2030 plan as long-term goals that are achieved through the building of healthy cities. Indicator systems should be put in place to assess progress and inform the public. Enhance research and education on healthy cities To develop new theories and practical solutions, cities should increase investment and form partnerships with universities, research institutes, and the private sector to support research and education on the best ways to create healthy cities.

Corporate Preferences for Domestic Policy Instruments Under a Sectoral Market Mechanism: A Case Study of Shanxi Province in China

Understanding companies’ preferences for various domestic policy instruments is crucial to designing and planning Sectoral Market Mechanism (SMM) in China. Based on a detailed overview of domestic policy instruments under SMM, this paper evaluates corporate preferences for diverse domestic policy instruments and identifies potential influencing factors through econometric analysis. The data were collected from 113 respondents in all 11 prefecture-level cities of Shanxi province, China. Regarding policy instruments under the system of government receiving tradable units, corporate energy saving potential, learning capacity and companies’ characteristics have shown significant influences on companies’ preferences. Dissemination and the popularization of knowledge are also important to help companies learn how to improve energy efficiency. In terms of policy measures with voluntary installation-level targets, corporate competition level, organizational size and ownership are the main factors influencing companies’ preferences. Reducing inequality in the distribution of responsibility is especially important to gain companies’ support. Under the policy with mandatory installation-level targets, it suggests that policymakers should focus on status of energy use management and internationalization orientation. Policy instruments familiar to companies that are able to relieve corporate financial pressures might be good options to gain higher acceptance. Moreover, our results show that it is very important to choose an issuance frequency of one to three years under sectoral crediting.

The Lancet Countdown on PM2·5 pollution-related health impacts of China's projected carbon dioxide mitigation in the electric power generation sector under the Paris Agreement: a modelling study

BACKGROUND Except for comparing the implementation costs of the Paris Agreement with potential health benefits at the national levels, previous studies have not explored the health impacts of the nationally determined contributions (NDCs) by countries and in regional details. In this Lancet Countdown study, we aimed to estimate and monetise the health benefits of Chinas NDCs in the electric power generation sector, and then compare them with the implementation costs, both at the national and regional levels. METHODS In this modelling study, we linked the Multi-regional model for Energy Supply system and their Environmental ImpaCts, the Multi-resolution Emission Inventory for China model, the offline-coupled Weather Research and Forecasting model, the Community Multiscale Air Quality model, and the Integrated Health Impact Assessment model with a time scope from 2010 to 2050. We calculated the PM2·5 concentrations and compared the health impacts and implementation costs between two scenarios that reflect CO2 and air pollutant emissions-the reference (REF) scenario (no climate policy) and the NDC scenario (100% realisation of NDC targets: CO2 emission intensity needs to be about 40% below 2010 emissions by 2030 [roughly 35% below 2030 emissions in REF], and about 90% below 2010 emissions by 2050 [roughly 96% below 2050 emissions in REF]). FINDINGS Under a comparatively optimistic health benefits valuation condition, at the national level, 18-62% of implementation costs could be covered by the health benefits in 2030. In 2050, the overall health benefits would substantially increase to 3-9 times of the implementation costs. However, northwest China would require the highest implementation costs and will also have more premature deaths because of a more carbon-intensive energy structure than business as usual. By 2030, people in northwest China (especially in Gansu, Shaanxi, and Xinjiang provinces) would need to bear worse air quality, and 10 083 (95% CI 3419-16 138) more premature deaths annually. This undesirable situation would diminish by about 2050. A solution that assumes no growth in air pollutant emissions in 2030 at the regional level is technically feasible, but would not be cost-effective. INTERPRETATION Our results suggest that cost-benefit analysis of climate policy that omits regional air pollution could greatly underestimate benefits. A compensation mechanism for inter-regional interests (including financial, technological, and knowledge support) should be established for regions that give up their human health benefits for the sake of the whole nation to realise the climate change targets. FUNDING National Natural Science Foundation of China and Cyrus Tang Foundation.

CO2 Emission Reduction Efforts Made by China's Electricity Sector and the International Comparison

Starting from the misunderstanding that China is doing little in controlling her greenhouse gas emissions along with the rapid economic growth, this paper tried to break this myth by looking into China’s electricity sector. It is found out that from 2000 to 2007, this sector was having great improvements in energy efficiency improvements, in demand side management and in reducing transmission losses and electricity consumed by power plants, ranked by their contributions to the overall sectoral emission reductions. The cumulative emission reductions from 2000 to 2007 amounted to 553 million tons, which means the unilateral emission reduction actions from China’s electricity sector alone helped the world exempt from a one-year national emission from a country as economically-powerful as United Kingdom. Other comparisons in generating efficiency side have been made between China and US. One suggestion for future work has been given at the end of the paper.

Coexistence of two types of spin glass phases in polycrystalline films of La2/3Ca1/3MnO3

The magnetoresistance (MR) and magnetization of La2/3Ca1/3MnO3 films with controllable grain sizes have been studied. Both quantities show differences between their zero-field cooled (ZFC) and field cooled (FC) states at low temperatures. The results indicate the coexistence of two types of spin glass phase at and nearby the grain boundaries: one forms a shell of a certain thickness and manifests itself in both MR and magnetization, and the other is nearly volume-less, manifesting itself only in MR.

Water conservation implications for decarbonizing non-electric energy supply: A hybrid life-cycle analysis

Low-carbon transition in the non-electric energy sector, which includes transport and heating energy, is necessary for achieving the 2 °C target. Meanwhile, as non-electric energy accounts for over 60% of total water consumption in the energy supply sector, it is vital to understand future water trends in the context of decarbonization. However, few studies have focused on life-cycle water impacts for non-electric energy; besides, applying conventional LCA methodology to assess non-electric energy has limitations. In this paper, a Multi-Regional Hybrid Life-Cycle Assessment (MRHLCA) model is built to assess total CO2 emissions and water consumption of 6 non-electric energy technologies - transport energy from biofuel and gasoline, heat supply from natural gas, biogas, coal, and residual biomass, within 7 major emitting economies. We find that a shift to natural gas and residual biomass heating can help economies reduce 14-65% CO2 and save more than 21% water. However, developed and developing economies should take differentiated technical strategies. Then we apply scenarios from IMAGE model to demonstrate that if economies take cost-effective 2 °C pathways, the water conservation synergy for the whole energy supply sector, including electricity, can also be achieved.