Charting a low carbon future for shipping: A UK perspective

Projected growth in the international shipping industry is set to outstrip CO₂ reductions arising from incremental improvements to technology and operations currently being planned and implemented. Using original scenarios, this paper demonstrates for the first time that it is possible for a nation's shipping to make a fair contribution to meeting global climate change commitments, but that this requires transformation of the sector. The scale and nature of technology change varies depending on the level of demand and how this is satisfied. The scenarios show that to develop successful marine mitigation policy, it is essential to consider the interdependencies between ship speed, level and pattern of demand for services, and the extent and rate of innovation in propulsion technology. Across the scenarios, it is difficult to foresee how deep decarbonisation can be achieved without an immediate, fleet-wide speed reduction; and a land-based energy-system transition strongly influences shipping demand, which in turn, influences the extent of required low-carbon propulsion technology change. Setting the industry on a 2 °C heading requires multifaceted and near-term changes in the shipping sector, but these are unlikely to materialise without a major shift by stakeholders to realise new and innovative deep decarbonisation policies in the coming decade.     

Global energy scenarios and their implications for future shipped trade

About half of the world's oil supply, a fifth of coal supply and a tenth of natural gas supply are traded by ship. Accordingly, any significant shift in the size and shape of the global energy system has important consequences for shipping, which underpins international trade and supports economic development. The Paris Agreement requires an acceleration of the drive towards energy system decarbonisation. Yet, the International Maritime Organisation's understanding of the future is more in line with the high-carbon scenarios analysed here. This paper is a first comprehensive and global assessment of implications of fundamental changes to global and regional energy systems for international shipping, under-researched in energy scenarios consistent with deep decarbonisation. It concludes that, despite uncertainties (particularly with negative emission technologies), fossil fuel trade by the middle of the century will almost certainly be significantly lower under low-carbon than under high-carbon scenarios, and (for oil and coal) lower than in 2012. As to bioenergy and captured carbon dioxide, while their supply is expected to increase during a low-carbon transition, worldwide shipped trade in these commodities will not necessarily grow, based on the analysis in this paper. In other words, if the low-carbon futures envisioned in the Paris Agreement materialise, energy-related shipping will likely decline (by a quarter for oil and by 50% for coal in the median < 2 °C scenarios by 2050), with significant ramifications for policies and regulation in the shipping sector and international trade.     

Nonlinear incremental analysis of fire-damaged r.c. base-isolated structures subjected to near-fault ground motions

Amplification of structural response of r.c. base-isolated structures is expected under near-fault ground motions, yet there is a lack of knowledge of their behavior in the case of fire. To investigate the nonlinear seismic response following a fire, an incremental dynamic analysis is carried out on five-storey r.c. base-isolated framed buildings with fire-protected High-Damping-Laminated-Rubber Bearings (HDLRBs), designed in line with the Italian seismic code. Horizontal components of near-fault ground motions characterized by forward-directivity or fling-step pulse-type are considered. The nonlinear seismic response of base-isolated structures in a no fire situation is compared with that in the event of fire, at 45 (i.e. R45) and 60 (i.e. R60) minutes of fire resistance, assuming both damaged (i.e. DS) and repaired (i.e. RS) stiffness conditions. Five fire scenarios are considered assuming the fire compartment confined to the area of the first level (i.e. F1), the first two (i.e. F1/2) and the upper (i.e. Fi, i=3–5) levels, with the parametric temperature–time fire curve evaluated in accordance with Eurocode 1. The nonlinear seismic analysis is performed by using a step-by-step procedure based on a two-parameter implicit integration scheme and an initial-stress-like iterative procedure. At each step of the analysis, plastic conditions are checked at the critical (end) sections of the girders and columns, where thermal mapping with reduced mechanical properties is evaluated with the 500 °C isotherm method proposed by Eurocode 2. A viscoelastic model with variable stiffness properties in the horizontal and vertical directions, depending on the axial force and lateral deformation, simulates the response of an HDLRB.     

北京平原地下水可持续开采方案分析

地下水过量开采已经引起北京平原地下水位持续下降,降落漏斗逐年扩大以及一系列环境问题。控制地下水开采,增加地下水补给以达到地下水可持续开采应当成为北京市水资源管理的重要任务。本文根据北京市中长期供水规划、水资源特点和地下水开采现状设计了4种地下水开发利用开采方案:即维持现状开采、增加补给量、减少开采量以及联合方案。运用已建北京平原地下水数值模拟模型对4个方案进行了模拟,分析了地下水系统水均衡量变化,地下水流场变化以及地下水动态变化,以此确定可能的可持续开发方案。结果表明,维持现状开采必将使含水层地下水疏干;增补和减开单独实施虽能改善现状,但难以实现。只有应用增补和减开的联合方案,才有可能实现地下水可持续开发。其为北京平原地下水资源的合理开发提供重要的依据。     

基于幕景分析法的土地开发整理规划环境影响评价——以江苏省涟水县为例

土地开发整理规划实施结果对规划区域内的生态环境产生重要影响。有关这方面的研究理论在我国尚少见报导,具体评价的方法、指标体系及模型构建均未形成规范性体系。本文以江苏省涟水县为例,运用幕景分析方法对《涟水县土地开发整理规划》(2000~2010)进行分析,并建立评价模型对规划前后的自然环境效应进行评价。结果表明:1997年涟水县的自然环境效应值低于2000年,其原因在于该县在这三年间,严格控制建设对耕地的占用,通过土地开发整理补充了更多的耕地。2010年自然态将来幕景得出的环境质量是下降的,原因是建设对农用地和未利用地的破碎化,加大了斑块密度。而2010年干扰态将来幕景与自然态相比,其自然生态正效应得到明显提升,增长了0.6736个百分点,表明合理设计土地开发整理规划对促进区域生态环境健康具有十分重要的作用。     

气候变化对藏东北牧业生产关键期的影响

利用藏东北10个气象站1961-2013年逐日平均气温资料,采用反距离权重插值法、线性回归、Mann-Kendall检验等方法,分析了牧草生长季(PGS)、牧草青草期(GGD)、牲畜抓膘期(FD)和牲畜掉膘期(FLD)等牧业生产关键期的时空变化,预估了未来50 a和100 a牧业生产关键期的变化.结果表明:近53 a PGS因结束日推迟而延长1.70 d·(10a)^-1,GGD平均每10 a延长1.53 d,牲畜抓膘开始期线性趋势不明显,结束期趋于推迟,FD平均每10 a延长1.84 d;牲畜掉膘开始日期显著推迟,结束日明显提前,FLD以-4.33 d·(10a)^-1的速度显著缩短.PGS的变化趋势与经度呈正相关,与海拔高度为负相关.PGS突变发生较早,出现在1998年;2005年是GGD明显变长的突变点,而FD和FLD的突变时间均发生在2003年.在10 a年际变化尺度上,近30 a PGS、GGD和FD呈逐年代增加趋势,而FLD趋于减少.如果气候按升温率0.044℃·a^-1变化,50 a后PGS、GGD和FD分别延长20.2、18.4和21.6 d,FLD缩短23.2 d;未来100 a PGS、GGD和FD可能分别延长40.3、36.9和43.2 d,FLD缩短46.5 d.这种变化趋势十分有利于藏东北牧草生产.     

Recursive cross-entropy downscaling model for spatially explicit future land uses: A case study of the Heihe River Basin

Downscaling methods assist decision makers in coping with the uncertainty regarding sustainable local area developments. In particular, they allow investigating local heterogeneities regarding water, food, energy, and environment consistently with global, national, and sub-national drivers and trends. In this paper, we develop a conceptual framework that integrates a partial equilibrium Global Biosphere Management Model (GLOBIOM) with a dynamic cross-entropy downscaling model to derive spatially explicit projections of land uses at 1-km spatial resolution from 2010 to 2050 relying on aggregate land demand projections. The fusion of the two models is applied in a case study in Heihe River Basin to analyze the extent of potential cropland, grassland, and unused land transformations, which may exacerbate already extensive water consumption caused by rapid expansion of irrigated agriculture in the case study region. The outcomes are illustrated for two Shared Socioeconomic Pathway scenarios. The kappa coefficients show that the downscaling results are in agreement with the land use and land cover map of the Heihe River Basin, which indicates that the proposed approach produces realistic local land use projections. The downscaling results show that under both SSP scenarios the cropland area is expected to increase from 2010 to 2050, while the grassland area is projected to increase sharply from 2010 to 2030 and then gradually come to a standstill after 2030. The results can be used as an input for planning sustainable land and water management in the study area, and the conceptual framework provides a general approach to creating high-resolution land-use datasets.     

Carbon dioxide emissions from Russia's electricity sector: future scenarios

Abstract

This article investigates future greenhouse gas emission scenarios for Russia's electricity sector, a topic of importance since Russia's ratification of the Kyoto Protocol in November 2004. Eleven scenarios are constructed to the year 2020 considering economic and technological details in both the demand and supply sides of the sector. The scenarios are based upon a thorough review of the different factors controlling carbon dioxide emissions, including potential economic growth, changes in energy efficiency and technological development, and that Russia may export large amounts of natural gas to European and Asian markets. The most likely scenario is that Russia will double industrial output over the next 10 years, increase energy efficiency in the demand sector, will remain consistent to the goals of the Energy Strategy 2020 and will implement more efficient technology in the electricity supply sector. Consequently, carbon dioxide emissions will still be 102 million tonnes below 1990 levels in 2010, representing a significant source for emission reduction credits available to be sold on international markets or transferred to the next crediting period.     

China's role in attaining the global 2°C target

In the recent climate change negotiations it was declared that the increase in global temperature should be kept below 2°C by 2100, relative to pre-industrial levels. China's CO₂ emissions from energy and cement processes already account for nearly 24% of global emissions, a trend that is expected to keep increasing. Thus the role of China in global GHG mitigation is crucial. A scenario analysis of China's CO₂ emissions is presented here and the feasibility of China reaching a low-carbon scenario is discussed. The results suggest that recent and continued technological progress will make it possible for China to limit its CO₂ emissions and for these emissions to peak before 2025 and therefore that the global 2°C target can be achieved.

Policy relevance

In signing the Copenhagen Accord, China agreed to the global 2°C target. Results from this article could be used to justify low-carbon development policies and negotiations. While many still doubt the feasibility of a low-carbon pathway to support the global 2°C target, the results suggest that such a pathway can be realistically achieved. This conclusion should increase confidence and guide the policy framework further to make possible China's low-carbon development. Related policies and measures, such as renewable energy development, energy efficiency, economic structure optimization, technology innovation, low-carbon investment, and carbon capture and storage (CCS) development, should be further enhanced. Furthermore, China can play a larger role in the international negotiations process. In the global context, the 2°C target could be reaffirmed and a global regime on an emissions mitigation protocol could be framed with countries’ emissions target up to 2050.     

Research progress and prospects of digital restructuring of global-local interactions北大核心CSCD

Global-local interaction is an important research topic in economic geography. In recent years, the rapid development of digitalization in various countries and regions has profoundly affected the global production and trade networks. However, there is a lack of systematic theoretical discussion on digitalization and global-local interaction studies. The objective of this study is to conceptually rethink the role of digitalization in reshaping global-local interactions from a dynamic and relational perspective. To do this, the study first systematically reviewed the digital turn in economic geography and discussed the rethinking of digitalization. It is found that the understanding of digitalization is gradually moving beyond the limits of isolated, static, and passive technocentric approaches and towards a more dynamic, relational, and open perspective. Second, the study combined the digital turn with the relational turn in relational economic geography, which constructs theoretical bridges between digitalization and global-local studies. Third, this study provided a basic understanding for sorting out the evolution of the research frameworks, that is, from the global value chain (GVC) to the global production network (GPN) and then to the digital ecosystem (DE). We argued that digitalization has been deeply involved in shaping the global economic landscape, restructuring global-local production relations, and reconstructing regional development. Based on this recognition, we discussed the primary performance of digitalization on the restructuring of global-local interaction from three aspects: enterprise relationship, spatial effect and interaction mechanism. Finally, grounded in the practice of China's urban and regional digital economy development, the possible theoretical innovations and prospects for future research on digitalization and global-local interaction in the Chinese context were proposed. The study pointed out that we can integrate the regional practices of China's digital development with more in-depth research from the perspectives of the platform ecosystems, spatial effects, location analysis, local development models, and so on in future research. © 2023, Editorial office of PROGRESS IN GEOGRAPHY. All rights reserved.