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61.
PSYCHIC is a process-based model of phosphorus (P) and suspended sediment (SS) mobilisation in land runoff and subsequent delivery to watercourses. Modelled transfer pathways include release of desorbable soil P, detachment of SS and associated particulate P, incidental losses from manure and fertiliser applications, losses from hard standings, the transport of all the above to watercourses in underdrainage (where present) and via surface pathways, and losses of dissolved P from point sources. The model can operate at two spatial scales, although the scientific core is the same in both cases. At catchment scale, the model uses easily available national scale datasets to infer all necessary input data whilst at field scale, the user is required to supply all necessary data. The model is sensitive to a number of crop and animal husbandry decisions, as well as to environmental factors such as soil type and field slope angle. It is envisaged that the catchment-scale model would provide the first tier of a catchment characterisation study, and would be used as a screening tool to identify areas within the catchment which may be at elevated risk of P loss. This would enable targeted data collection, involving farm visits and stakeholder discussion, which would then be followed up with detailed field-scale modelling. Both tiers allow the effects of possible mitigation options at catchment scale (Tier 1) and field scale (Tier 2) to be explored. The PSYCHIC model framework therefore provides a methodology for identifying critical source areas of sediment and P transfer in catchments and assessing what management changes are required to achieve environmental goals.  相似文献   
62.
Research on urban climate action has identified a broad range of potential factors explaining why and how local governments decide to tackle climate change. However, empirical evidence linking such factors in order to explain actual urban climate action has so far been mixed. To address this roadblock, our paper relies on a novel approach, postulating that different configurations of factors may lead to the same outcome (“equifinality”), through a qualitative comparative analysis (QCA). It is based on an available data set of local climate mitigation plans in 885 European cities. We find that urban climate action is systematically associated with four qualitatively different configurations of factors, each with its own consistent narrative (“networker cities”, “green cities”, “lighthouse cities”, “fundraising cities”). Crucially, some factors play a positive role in some configurations, a negative in others, and no role in further configurations (e.g., whether a city is located in a country with supportive national climate policies). This confirms that there is no single explanation for urban climate action. Achieving greater robustness in empirical research about urban climate action may thus require a shift, both conceptual and methodological, to the interactions between factors, allowing for different explanations in different contexts.  相似文献   
63.
2022年4月4日,IPCC第六次评估报告第三工作组《气候变化2022:减缓气候变化》报告和决策者摘要发布。报告全面评估了2010年以来减缓气候变化领域的最新科学进展,为国际社会深度认识和理解全球温室气体排放情况、不同温升水平下的减排路径以及可持续发展背景下的气候变化减缓和适应行动等提供了重要科学依据。基于报告主要结论,围绕温室气体排放的区域差异、减缓路径分类、与土地利用相关的排放评估及CO去除技术评估等方面的亮点,文中提出在应对气候变化减缓政策行动中,中国应坚定“双碳”战略目标,在综合考虑经济发展阶段和资源禀赋差异背景下,将可持续发展、公平和消除贫困植根于社会发展愿景中实施减缓路径,并加快提升气候变化综合评估核心科学技术的研发进度,以进一步提升国际影响力和话语权。  相似文献   
64.
近年来,碳捕集利用与封存(CCUS)作为减缓气候变化的关键技术之一,得到国际社会广泛关注。政府间气候变化专门委员会(IPCC)第六次评估报告(AR6)第三工作组报告对CCUS进行了重新定位,并围绕减排潜力、减排成本、综合效益及应用前景等方面,对CCUS相关技术进行了系统全面评估。结论显示,CCUS技术是全球气候目标实现不可或缺的减排技术组合,到21世纪中叶有潜力实现累积千亿吨级减排效应,但当前CCUS技术成熟度整体处于示范阶段,成本较高,减排潜力有待进一步释放。综合考虑CCUS可以有效降低巨额资产搁浅风险、具有良好社会环境效益等因素,我国应结合自身“富煤、贫油、少气”的资源禀赋和基本国情,将CCUS作为战略性技术,统筹政策顶层设计、加速技术体系构建、探索市场激励机制、加强国际科技合作,促进CCUS技术发展。  相似文献   
65.
Marine seismic exploration has potentially detrimental effects upon marine life and marine mammals in particular. Potential effects range from disturbance that may lead to displacement from feeding or breeding areas, to auditory damage and potential mortality. Nations including the USA, Canada and Brazil have followed the example set by the United Kingdom by introducing guidelines to minimise acoustic disturbance to marine mammals. This paper describes the mitigation measures central to the guidelines currently in place, and identifies the similarities, differences and deficiencies within them. A need for further review by some nations is identified, with a recommendation that an international standard should be produced, benefiting both the geophysical exploration industry and the conservation community.  相似文献   
66.
Climate change presents a threat to the sustainability of cities and their societies, and must be adequately addressed. Urban environments (cities) are responsible for the creation of a significant amount of greenhouse gas emissions which are the source of climate change. Cities have been increasingly the focus of action to address climate change, yet emissions are not significantly reducing. Additionally, there a lack of integration between adaptation and mitigation. This prevents responses adequate to limit global warming to 1.5OC, and to be well adapted to anticipated changes. This paper critically analyses existing definitions and typologies of climate change actions. A definition of ‘climate change transformation’ is proposed which includes the integration of adaptation and mitigation goals to enable a new regime in which global warming is limited to 1.5OC. A new three-part typology: ‘coping, malaction and transformation,’ is presented for categorising climate change actions by the extent to which they integrate adaptation and mitigation, and define a new regime. The typology is accompanied by illustrations to demonstrate the relationship between adaptation and mitigation. The definition, typology and illustration serve to guide effective climate change decision making, and provides principles to guide application in urban environments.  相似文献   
67.
Through their consumption behavior, households are responsible for 72% of global greenhouse gas emissions. Thus, they are key actors in reaching the 1.5 °C goal under the Paris Agreement. However, the possible contribution and position of households in climate policies is neither well understood, nor do households receive sufficiently high priority in current climate policy strategies. This paper investigates how behavioral change can achieve a substantial reduction in greenhouse gas emissions in European high-income countries. It uses theoretical thinking and some core results from the HOPE research project, which investigated household preferences for reducing emissions in four European cities in France, Germany, Norway and Sweden. The paper makes five major points: First, car and plane mobility, meat and dairy consumption, as well as heating are the most dominant components of household footprints. Second, household living situations (demographics, size of home) greatly influence the household potential to reduce their footprint, even more than country or city location. Third, household decisions can be sequential and temporally dynamic, shifting through different phases such as childhood, adulthood, and illness. Fourth, short term voluntary efforts will not be sufficient by themselves to reach the drastic reductions needed to achieve the 1.5 °C goal; instead, households need a regulatory framework supporting their behavioral changes. Fifth, there is a mismatch between the roles and responsibilities conveyed by current climate policies and household perceptions of responsibility. We then conclude with further recommendations for research and policy.  相似文献   
68.
Through their consumption behavior, households are responsible for 72% of global greenhouse gas emissions. Thus, they are key actors in reaching the 1.5 °C goal under the Paris Agreement. However, the possible contribution and position of households in climate policies is neither well understood, nor do households receive sufficiently high priority in current climate policy strategies. This paper investigates how behavioral change can achieve a substantial reduction in greenhouse gas emissions in European high-income countries. It uses theoretical thinking and some core results from the HOPE research project, which investigated household preferences for reducing emissions in four European cities in France, Germany, Norway and Sweden. The paper makes five major points: First, car and plane mobility, meat and dairy consumption, as well as heating are the most dominant components of household footprints. Second, household living situations (demographics, size of home) greatly influence the household potential to reduce their footprint, even more than country or city location. Third, household decisions can be sequential and temporally dynamic, shifting through different phases such as childhood, adulthood, and illness. Fourth, short term voluntary efforts will not be sufficient by themselves to reach the drastic reductions needed to achieve the 1.5 °C goal; instead, households need a regulatory framework supporting their behavioral changes. Fifth, there is a mismatch between the roles and responsibilities conveyed by current climate policies and household perceptions of responsibility. We then conclude with further recommendations for research and policy.  相似文献   
69.
Insights into flood mitigation behaviour are important because of the ongoing shift to risk-based flood management approaches in Europe and worldwide, which envisage a contribution from flood-prone households to risk reduction. The recent literature on factors that influence flood mitigation behaviour indicates that flood-coping appraisal is an important variable to understand and explain flood mitigation behaviour. Coping appraisal originates from Protection Motivation Theory (PMT), and refers to the cognitive process that people undergo when evaluating their own ability to avoid a certain risk. However, the empirical literature on the importance of coping appraisal is still scarce, and, in particular, little is known about the independent influence of the three single components of coping appraisal on precautionary behaviour: namely, response efficacy, self-efficacy, and response cost. This study presents the results of a recent survey among 752 flood-prone households along the river Rhine in order to provide detailed insights into the influence of the components of flood-coping appraisal on four different types of flood mitigation behaviour: structural building measures, adapted building use, the deployment of flood barriers, and the purchase of flood insurance. The results confirm that flood-coping appraisal is an important variable in terms of precautionary behaviour. In particular, both response efficacy and self-efficacy contribute to the models which explain the four different types of flood-mitigation behaviour. Based on these findings, it is concluded that risk communication should focus more strongly on the potential of flood-mitigation measures to effectively reduce or avoid flood damage, as well as on information about how to implement such measures in practice.  相似文献   
70.
As part of the Copenhagen Accord, Annex I Parties (industrialised countries) and non-Annex I Parties (developing countries) have submitted reduction proposals (pledges) and mitigation actions to the UNFCCC secretariat. Our calculations show that if the current reduction offers of Annex I and non-Annex I countries are fully implemented, global greenhouse gas emissions could amount to 48.6-49.7 GtCO2eq by 2020. Recent literature suggests that the emission level should be between 42 and 46 GtCO2eq by 2020 to maintain a “medium” chance (50-66%) of meeting the 2 °C target. The emission gap is therefore 2.6-7.7 GtCO2eq. We have identified a combined set of options, which could result in an additional 2.8 GtCO2eq emission reduction. This would lead to an emission level just within the range needed. The options include reducing deforestation and emissions from bunker fuels, excluding emissions allowance increases from land use and forestry rules, and taking into account the national climate plans of China and India. However, there are also important risks that could widen the emissions gap, like lower reductions from countries with only a conditional pledge and the use of Kyoto and/or trading of new surplus emission allowances.  相似文献   
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