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Ethylene is one of the most important products in the emissions-intensive petrochemical industry. Decarbonizing the ethylene industry is thus important for achieving global carbon neutrality. This study is the first to explore future long-term zero-emissions production pathways for the ethylene industry in China, the world's biggest ethylene producer. An optimization model was built in the context of China's carbon neutrality target of 2060. Four scenarios were developed where the policy ambitions for climate mitigation and for plastic management including waste were varied. Based on this, authors assessed the cumulative total emissions, technology options, future geographical location of ethylene production, and policy challenges associated with each scenario. This is also the first time that scope 3 emissions from waste incineration are included, motivated by the short lifetime of most ethylene products. Results show the cumulative CO 2 emissions for the scenarios differ considerably, ranging from 4.3 to 7.8 Gt, even if carbon neutrality by 2060 is achieved in all scenarios. The results suggest that ambitious plastic focused policies can result in lower costs and less cumulative emissions compared to ambitious climate focused policies. The results demonstrate the importance of adopting CCS for waste incineration. This reduces cumulative CO 2 emissions by up to 2 Gt. However, reduced overall demand and increased recycling rates should be priority options due to CCS challenges. Results suggest Chinese ethylene industry should adopt a mixed portfolio of production technologies, where the share of emission-intensive coal-based methanol-to-olefins is limited. These findings on decarbonization pathways can contribute to achieving the Paris agreement. [Display omitted] • Ambitious plastic policies lead to 1.3 Gt less cumulative CO 2 than climate policies. • Cumulative CO 2 until 2060 can be reduced by 3.5 Gt compared to reference scenario. • Adopting CCS in incineration can reduce cumulative CO 2 emissions by 2 Gt. • Ethylene industry should adopt a mixed production portfolio due to uncertainties. • Coal-based MTO with CCS does not appear to be a cost-competitive option. [ABSTRACT FROM AUTHOR]

Promoting the adoption and maintenance of low-carbon consumption behaviors (LCBs) is a global climate action. Most prior studies have considered only the adoption of LCBs and not explored how behavioral characteristics and emotions influence individual behaviors. To address these limitations, this study builds a dual-level integrated model to detect the maintenance rate of various LCBs and identify what factors affect behavioral maintenance. Using data collected from 2052 residents in China, generalized linear mixed models are employed to examine the effects of behavioral and individual-level factors and of social interaction on the maintenance of LCBs. Robustness is checked using the instrumental variable method, least-squares dummy variable method, and Probit approach. The estimated maintenance rate for different LCBs ranges between 29.02 % and 83.49 %, while the estimated cessation rate ranges between 2.31 % and 6.58 %. Maintenance of LCBs is positively affected by context stability but negatively influenced by effort expectancy. Anticipated guilt is identified as the strongest driver (positive) of maintenance of LCBs for all tested variables, followed by symbol expectancy. However, neither behavior routinization nor anticipated pride is found to be significantly associated with behavioral maintenance. The effects of anticipated guilt, effort expectancy, and symbol expectancy on behavioral maintenance are moderated by social interaction. Regarding demographics, family size is positively associated with behavioral maintenance, while females are more likely than males to maintain LCBs. These findings address the under-studied effects of behavioral characteristics and emotions on behavioral maintenance, and provide new insights for redefining target interventions to engage the public in maintaining LCBs. [Display omitted] • Maintenance of low-carbon consumption behaviors (LCBs) is studied. • A dual-level integrated model incorporating social interaction is built. • Maintenance rate of LCBs is estimated between 29.02 % and 83.49 %. • Anticipated guilt is the strongest driver (positive) of maintenance of LCBs. • Symbol expectancy and context stability contribute to maintaining of LCBs. [ABSTRACT FROM AUTHOR]

While feeding 20% of global population, China's agriculture is a large greenhouse gas (GHG) emitter, posing a major challenge to the country's carbon neutrality target. However, the pathways of agriculture towards carbon neutrality remain unclear. To address this knowledge gap, we conduct a comprehensive life-cycle assessment and show that valorization of sustainable biomass wastes (crop residues, forest residues, livestock manure, food waste, and sewage sludge) into biochar can contribute importantly towards agricultural carbon neutrality in China. The maximum potential of biochar production from these waste resources in 2018 is 145 Mt yr−1 with a corresponding GHG mitigation potential of 455.7 (405.5–572.4) Mt CO 2 -eq yr−1. This can fully offset the total CH 4 and N 2 O emissions from China's croplands (∼400 Mt CO 2 -eq yr−1), which are difficult to be entirely eliminated due to rice paddy irrigation and intensive use of fertilizers. Distribution of biomass waste varies across regions, and at the national level , crop residues (48.8%) and livestock manure (25.4%) and food waste (15.6%) are the main sources of biochar feedstocks and should be prioritized in biochar development. Forest residues have a marginal contribution due to competing uses from other sectors, and sewage sludge derived biochar is a net source of GHG emissions due to the large energy consumption required for sludge drying. The total GHG mitigation potential of biochar is greatly affected by pyrolysis temperature and the highest mitigation effect is observed under 300–500 °C. These results underscore the benefit of sustainable biochar production to agricultural carbon neutrality, and to maximize the climate benefit requires differential policies and pyrolysis technologies tailored to regional availability of biomass resources. • The GHG mitigation potential of sustainable biochar in China was analyzed. • The maximum mitigation potential can offset all CH 4 and N 2 O emission from croplands. • Biochar GHG mitigation potential is affected significantly by pyrolysis temperature. • Sustainable biochar can contribute toward agricultural carbon neutrality. [ABSTRACT FROM AUTHOR]

Promoting technology development co-operation is particularly relevant while addressing global climate change or regional pollution. Investors may contribute to increasing environmental-related patents, which may help to improve the quality of the environment as long as supported by proper regulations and policies. In the quest towards a cleaner environment via the mitigation of climate change, this study investigates the relationship between technological innovation, income level, renewable energy and carbon emissions in both the United States and China. Applying the dynamic auto-regressive distributive lag (DARDL) simulation method revealed varying impacts of regressors on CO 2 emissions in the short-run and long-run. Accordingly, this study empirically confirms that (i) technological innovation reduces carbon emissions in the United States but it is not statistically significant in China. (ii) Renewable energy reduces carbon emissions in both countries. (iii) The impact of income level on emissions decreases from short-run to long-run in both countries. Decision-makers in China should stimulate more effective environmental-related innovations to decrease CO 2 emissions and should permit easy access to environmental-related patents together with reducing its cost of registration. • Investigates the role of green technological innovation in decreasing CO 2 emissions. • Applies the novel Dynamic ARDL simulation. • Green technological innovation reduces CO 2 emissions in the U.S. Only. • Confirms that renewable energy mitigates CO 2 emissions both in the U.S. and China. [ABSTRACT FROM AUTHOR]