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931.
This article outlines a critical gap in the assessment methodology used to estimate the macroeconomic costs and benefits of climate and energy policy, which could lead to misleading information being used for policy-making. We show that the Computable General Equilibrium (CGE) models that are typically used for assessing climate policy use assumptions about the financial system that sit at odds with the observed reality. These assumptions lead to ‘crowding out’ of capital and, because of the way the models are constructed, negative economic impacts (in terms of gross domestic product (GDP) and welfare) from climate policy in virtually all cases.

In contrast, macro-econometric models, which follow non-equilibrium economic theory and adopt a more empirical approach, apply a treatment of the financial system that is more consistent with reality. Although these models also have major limitations, they show that green investment need not crowd out investment in other parts of the economy – and may therefore offer an economic stimulus. Our conclusion is that improvements in both modelling approaches should be sought with some urgency – both to provide a better assessment of potential climate and energy policy and to improve understanding of the dynamics of the global financial system more generally.

POLICY RELEVANCE

This article discusses the treatment of the financial system in the macroeconomic models that are used in assessments of climate and energy policy. It shows major limitations in approach that could result in misleading information being provided to policy-makers.  相似文献   

932.
The voluntary carbon market allows participants to go beyond regulatory carbon offsetting. Recent developments have improved the transparency and credibility of voluntary carbon trading, and forest carbon credit transactions constitute more than half of trade volume. Its workings, however, have not been sufficiently explored in the literature. This study analyses the characteristics of forest carbon credit transactions in the voluntary carbon market using frequency analysis and logistic regression analysis. The results reveal that the co-benefits of forest carbon projects are an important factor influencing carbon credit transactions. From the higher transaction ratio of credits from CCB Standards-labelled projects and projects using co-benefit-oriented standards, it can be inferred that credits with potential for co-benefits (e.g. fostered corporate social responsibility, social cohesion of local communities and voluntary leadership, and positive environmental impacts) are preferred to those focusing exclusively on emission reduction in the voluntary carbon market. The findings of this study suggest that developing co-benefits is important for strengthening the market competitiveness of forest carbon credits in the voluntary carbon market. Additionally, unlike the compliance carbon market, in the voluntary carbon market stringent carbon standards do not always guarantee credit transaction performance.

POLICY RELEVANCE

After UNFCCC COP-21, the global society agreed to acknowledge various forms of international carbon crediting mechanisms, and noted the significance of greenhouse gas emissions reduction for sustainable development and environmental integrity through the Paris Agreement. Moreover, the agreement encouraged both REDD+ activities in developing countries and supports from developed countries. Additionally, co-benefits of forest carbon projects are important for credit transaction in the global voluntary carbon market. Under the new climate regime, co-benefits of forest carbon projects are expected to gain attention in the carbon market. To promote the social, economic, and environmental co-benefits of forest carbon projects, the introduction of an objective co-benefit assessment and certification system should be reviewed at the national level.  相似文献   

933.
2011年以来,我国碳排放权交易市场建设不断加快,碳排放权交易机制不断健全完善,其中基准线法被确定为全国碳交易初始配额分配的主要方法。电解铝行业是我国能源消耗和碳排放的重点部门,尽早将该行业纳入碳市场对于行业减排、纵深推进全国碳市场交易以及应对国际碳边境调节机制政策均有重要意义。基于2018年电解铝行业直报的碳排放相关数据,确定了我国电解铝行业开展全国碳交易的基准线方案。结果显示,电解铝行业宜选取8.12~8.15 t CO2/t铝作为基准线取值,不需设置区域差异调整系数。同时为保证电解铝行业碳交易的顺利开展,还需尽快确定行业配额方案,进一步完善企业排放量的监测、报告和核查以提高核查填报数据质量,以及进一步研究电解铝行业碳排放核算的范围。  相似文献   
934.
目前欧盟、中国、日本、韩国、加拿大,以及南非等国家或地区,已经公布了温室气体中和或者碳中和的目标,如果加上很可能很快也会提出碳中和目标的美国,全球有可能近70%的CO2排放的国家或地区提出碳中和的目标。由于这些国家或地区是全球技术主导和经济主导地,因而全球2050年左右实现碳中和具有可行性。2050年左右实现碳中和,即和《巴黎协定》2℃目标,甚至和其1.5℃温升目标下的减排路径相一致。研究表明实现2050年左右碳中和有其可行性,实现该目标需要更多的技术创新,未来将是各个国家技术竞争和经济竞争阶段。  相似文献   
935.
The emissions reduction pledges made by individual countries through the 2015 Paris Agreement represent the current global commitment to mitigate greenhouse gas emissions in the face of the enduring climate crisis. Natural lands carbon sequestration and storage are critical for successful pathways to global decarbonization (i.e., as a negative emissions technology). Coastal vegetated habitats maintain carbon sequestration rates exceeding forest sequestration rates on a per unit area basis by nearly two orders of magnitude. These blue carbon habitats and their associated carbon sequestration benefits are vulnerable to losses from land-use change and sea-level rise. Incorporation of blue carbon habitats in climate change policy is one strategy for both maintaining these habitats and conserving significant carbon sequestration capabilities. Previous policy assessments have found the potential for incorporation of coastal carbon sequestration in national-level policies, yet there has – to date – been little inclusion of blue carbon in the national-scale implementation of Paris commitments. Recently, sub-national jurisdictions have gained attention as models for pathways to decarbonization. However, few previous studies have examined sub-national level policy opportunities for operationalizing blue carbon into climate decision-making. California is uniquely poised to integrate benefits from blue carbon into its coastal planning and management and its suite of climate mitigation policies. Here, we evaluated legal authorities and policy contexts addressing sequestration specifically from blue carbon habitats. We synthesized the progressive action in California’s approaches to mitigate carbon emissions including statutory, regulatory, and non-regulatory opportunities to incorporate blue carbon ecosystem service information into state- and local-level management decisions. To illustrate how actionable blue carbon information can be produced for use in decision-making, we conducted a spatial analysis of blue carbon sequestration in several locations in California across multiple agencies and management contexts. We found that the average market values of carbon sequestration services in 2100 ranged from $7,730 to $44,000 per hectare and that the social cost of carbon sequestration value was 1.3 to 2.7 times the market value. We also demonstrated that restoration of small areas with high sequestration rates can be comparable to the sequestration of existing marshes. Our results illustrate how accessible information about carbon sequestration in coastal habitats can be directly incorporated into existing policy frameworks at the sub-national scale. The incorporation of blue carbon sequestration benefits into sub-national climate policies can serve as a model for the development of future policy approaches for negative emissions technologies, with consequences for the success of the Paris Agreement and science-based decarbonization by mid-century.  相似文献   
936.
As a hard-to-abate sector, the iron and steel industry is responsible for 22% of China’s total carbon emissions and therefore plays a crucial role in achieving China’s carbon peaking and neutrality target. Nearly 90% of China’s iron and steel output is produced with coal-based blast furnaces, which results in high carbon emission intensity. To peak China’s carbon emissions and achieve the carbon neutrality target, it is essential to accelerate the application of breakthrough technologies such as carbon capture and storage (CCS) and hydrogen-based steel-making. This paper estimates the future CO2 emissions from China’s iron and steel industry in pathways that consider the influence of different technology portfolios, technology maturity, decarbonization of power systems, and future steel production output. The results show that using currently available technology, China’s iron and steel industry can reduce CO2 emissions by more than 50%. However, it cannot achieve the neutrality target without using innovative technologies. By combining conventional strategies with net-zero emission technologies such as CCS and hydrogen metallurgy, approximately 80–90% emission reduction can be achieved, thus leading to a carbon neutrality pathway, which can meet the 1.5°C targets of the carbon budget limit either. In the future, carbon emissions' reduction potential will be influenced by the decarbonization of power systems and the diffusion rate of innovative technologies. To achieve carbon neutrality, it is essential to act sooner and faster.  相似文献   
937.
Efforts to deliver on net zero emissions targets are set to rely on carbon dioxide removal (CDR) methods. Democratic, trustworthy and socially intelligent research, development, demonstration and deployment of CDR methods in aid of net zero will be highly dependent on how different publics evaluate them, and ultimately which groups support or oppose them. This paper develops a novel, nationally representative method for the multi-criteria appraisal of five policy relevant CDR methods – plus an option not to pursue CDR at all – by members of the British public (n = 2,111). The results show that the public supports the inclusion of CDR in UK climate policy. CDR methods often characterised as ‘natural’ or ‘nature-based’ are appraised more highly than ‘technological’ ones, in the descending order: habitat restoration, afforestation, wood in construction, bioenergy with carbon capture and storage, and direct air carbon capture and storage. Yet, there is no significant disagreement in the appraisal of technological methods and they therefore may be less polarizing, suggesting that popular preconceptions of what is natural – and therefore more attractive – may be holding them back. CDR methods being mainly developed by public sector and non-governmental organisations are also appraised more highly than those being developed by private interests. Regional differences in option appraisal reveal where particular CDR methods are more or less likely to be supported or opposed; stressing the importance of matching physical requirements for CDR with appropriate social contexts. Demographic and socio-economic analyses show that people who appraise CDR methods most highly tend to be older respondents, male, or of a higher social grade. Finally, those with hierarchical worldviews and who voted ‘leave’ in the UK’s referendum on EU membership are less supportive of CDR than those with egalitarian worldviews and who voted ‘remain’.  相似文献   
938.
Carbon removal – also known as negative emissions technologies, or greenhouse gas removal – represents a core pillar of post-Paris climate policy, signaling for enhancing and constructing carbon sinks to balance emissions sources on route to ambitious temperature targets. We build on Amory Lovins’ “hard” and “soft” alternatives for energy pathways to illuminate how foundational experts, technologists, and policy entrepreneurs think about different modes of resource inputs, infrastructure and livelihoods, and decision-making, regarding ten nature-based and engineered carbon removal approaches. Based on 90 original interviews, we show that hard and soft paths reflect different conceptions of systems, spaces, and societal involvement. We highlight that pathways depend on diverging concepts of economies-of-scale (capturing carbon at the largest possible scale, versus catalyzing systemic co-benefits) and carbon management (a waste product within conventional climate governance, versus diverse end-uses and values to be diversely governed). Our analysis further emphasizes two key uncertainties: whether renewables can be upscaled to allow synergies rather than tradeoffs between carbon removal and more widespread energy demands, and whether carbon certification can expand spatially to navigate long supply chains, and conceptually to incentivize diverse co-benefits. Experts remain motivated by antecedent concerns over land-use management and extractive industries, and that exploitative systems will – without guardrails – be replicated by inertia.  相似文献   
939.
Voluntary offsetting of flight-related emissions is an important cornerstone of passengers’ individual efforts to contribute to climate change mitigation. Hence, many scientific studies have tried to assess people’s willingness-to-pay to offset their own flight-related carbon emissions. Up-to-date, these studies are overwhelmingly grounded in hypothetical stated-preference approaches, with very limited knowledge about external validity. Here, we report on an observational field study involving a final sample of 63,520 bookings made with a European airline, allowing us to gauge actual willingness-to-pay for carbon dioxide compensation in a revealed-preference approach. Our pre-registered study shows that the median willingness-to-pay to voluntarily offset a ton of carbon dioxide from flight-related emissions is zero, with the mean willingness-to-pay being around 1 EUR. Aggregated voluntary willingness-to-pay thus dramatically falls short of current prices to offset carbon dioxide, for example through the EU-ETS. Our results thereby question the suitability of self-reported, hypothetical assessments of offsetting and raise caution about the effectiveness of offsetting schemes, which currently do not very successfully internalize flight-related cost of emissions.  相似文献   
940.
有机碳和有机分子碳同位素的地球化学意义   总被引:4,自引:0,他引:4  
有机碳和有机分子碳同位素组成的研究不仅在沉积地层对比,油-油,油-源对比研究方向发挥了独特作用,而且在古气候,古环境研究方面更具有广阔的应用剪影。开展对全球气候变化及全球碳循环有重要意义的有机碳碳同位素组成及分布研究和对生物演化,恢复古生态,古环境有重要意义的化石及沉积物中有机分子的碳同位素成及分布研究已势在必行。  相似文献   
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