A GIS approach to modelling CO2 emissions associated with the pupil-school commute

Concerns have been raised in numerous countries over declining rates of active transport to school. In a UK context, the pupil-school commute is estimated to contribute around 658 kilotonnes of CO₂ per year; however, tackling this issue effectively requires an improved understanding of how emissions can be modelled and mapped over a variety of scales. This paper implements a new estimation technique for the modelling of CO₂ emissions linked with the school commute that integrates both transport network-level routing and geographically disaggregate vehicle emissions data. The model is then applied to a national cohort of pupils in England. Areas demonstrating the highest emissions were typically more rural and/or comprising more affluent resident populations. Emissions were also shown to increase with school year, with larger step changes between educational stages reflecting the different geography of school locations. Furthermore, where secondary school entry policies were selective or based on a religious domination, average emissions were typically higher than in non-selective schools.     

Carbon dioxide concentration and flux in an urban residential area in Seoul,Korea

The carbon dioxide （CO2） concentrations and fluxes measured at a height of 17.5 m above the ground by a sonic anemometer and an open-path gas analyzer at an urban residential site in Seoul, Korea from February 2011 to January 2012 were analyzed. The annual mean CO2 concentration was found to be 750 mg m-3, with a maximum monthly mean concentration of 827 mg m-3 in January and a minimum value of 679 mg m-3 in August. Meanwhile, the annual mean CO2 flux was found to be 0.45 mg m-2 s-1, with a maximum monthly mean flux of 0.91 mg m-2 s-1 in January and a minimum value of 0.19 mg m-2 s-1 in June. The hourly mean CO2 concentration was found to show a significant diurnal variation; a maximum at 0700-0900 LST and a minimum at 1400-1600 LST, with a large diurnal range in winter and a small one in summer, mainly caused by diurnal changes in mixing height, CO2 flux, and surface complexity. The hourly mean CO2 flux was also found to show a significant diurnal variation, but it showed two maxima at 0700-0900 LST and 2100-2400 LST, and two minima at 1100-1500 LST and 0300-0500 LST, mainly caused by a diurnal pattern in CO2 emissions and sinks from road traffic, domestic heating and cooking by liquefied natural gas use, and the different horizontal distribution of CO2 sources and sinks near the site. Differential advection with respect to wind direction was also found to be a cause of diurnal variations in both the CO2 concentration and flux.     

南北极区冬春季节大气平流层CO次峰现象

ACE-FTS（加拿大“大气化学实验”的傅里叶变换光谱仪）和Aura-MLS（美国Aura卫星的微波临边探测器）卫星CO观测资料的分析结果显示,南北半球极区大气平流层中部,于当地冬末春初季节存在明显的CO浓度垂直分布次峰值现象。应用观测密度较大、范围覆盖较广的Aura-MLS卫星资料,通过对冬春季节极区CO浓度的季节内变化进行分析后发现,冬季来自大气中间层富含CO的空气能够逐渐下沉并进入到平流层中部,在冬末春初时节,平流层上部的CO浓度快速下降,而平流层中部的CO浓度变化则较慢,从而使大气平流层中CO浓度呈现悬球状的空间分布结构,卫星观测廓线资料分析结果则呈现出次峰值现象。相应的同化气象数据MERRA的风场资料和Aura-MLS卫星观测OH资料分析结果表明,垂直输送的减弱、水平交换的加强和OH浓度的回升可能是导致平流层上部CO浓度快速减少的原因,而在平流层中部极低的OH浓度以及极弱的水平交换使CO保持较长的化学寿命,并使这一现象得以从晚冬维持到春季。     

中国旅游业能源消耗与CO2排放量的初步估算

随着旅游产业规模的不断壮大,旅游业对气候、环境的影响日益引起国际机构和社会各界的关注.旅游业能源利用及二氧化碳排放是旅游对环境影响的重要驱动力之一,成为近5年来世界旅游研究的新兴热点.旅游产业特点决定了旅游业能源消耗和二氧化碳排放量的测算是个世界性的难题.本文采用"自下而上"法,通过文献研究与数理统计方法,首次系统估算...     

贸易对中国产业能源活动碳排放的影响

研究对外贸易对我国碳排放的影响,可以分清我国碳排放的来源,有利于我国合理制定碳减排政策和科学应对全球气候变化问题.当前有关国际贸易中隐含碳排放的研究大多没有处理好加工贸易这一重要因素.本文在理清区域间相互贸易中隐含碳排放的复杂关系基础上利用非竞争型投入产出表模型,构建了两区域产业能源活动碳排放联系模型,将直接排放分解为...     

二氧化碳羽流地热系统水-岩-气相互作用:以松辽盆地泉头组为例

二氧化碳羽流地热系统(CPGS)是利用CO2地质储存场地进行地热能开发的一种工程技术,也是整合CO2减排与开发深部地热资源的理想方式。但伴随着对深部地热的提取,注入储层的超临界CO2使深部咸水的pH值降低,导致周围岩体产生溶解和沉淀,从而引起孔隙度、渗透率等地层物性的变化,最终改变系统的生产能力和净热提取效率。以松辽盆地泉头组为目标储层,采用室内实验、数值模拟等技术手段,通过实验和数值计算结果的对比,揭示系统水-岩-气相互作用对热储矿物组分的改变。研究结果显示:实验过程中矿物溶解对温度和盐度变化较为敏感,而受压力影响较小;在实验和模拟时间内发生溶解的矿物主要是长石类矿物,方解石在反应后全部溶解;石英、伊利石和高岭石的矿物组分体积分数有所增加,并有少量菱铁矿生成。     

http://www.sciencedirect.com/science/article/pii/S1674987114000590

This paper reviews the origin and evolution of fluid inclusions in ultramafic xenoliths,providing a framework for interpreting the chemistry of mantle fluids in the different geodynamic settings.Fluid inclusion data show that in the shallow mantle,at depths below about 100 km,the dominant fluid phase is CO_2±brines,changing to alkali-,carbonate-rich(silicate) melts at higher pressures.Major solutes in aqueous fluids are chlorides,silica and alkalis(saline brines;5-50 wt.%NaCl eq.).Fluid inclusions in peridotites record CO_2 fluxing from reacting metasomatic carbonate-rich melts at high pressures,and suggest significant upper-mantle carbon outgassing over time.Mantle-derived CO_2(±brines) may eventually reach upper-crustal levels,including the atmosphere,independently from,and additionally to magma degassing in active volcanoes.     

洋底高原：了解地球内部的窗口

洋底高原是洋壳的重要组成部分,它是分布在洋底的一种面积广大、且具有异常洋壳厚度的区域。洋底高原通常规模巨大,绝大多数喷发于大洋环境,岩石组成主要为镁铁质到超镁铁质,岩石类型主要为拉斑玄武岩。大多数洋底高原的岩石组成较为相似,而且均形成于一期或两期时间较短却大规模集中喷发的岩浆活动,目前认为是大规模的热地幔物质从地幔深部上升到岩石圈底部,由于巨大地幔柱头部（地幔羽）引起的熔融作用形成的。正是由于洋底高原与地幔柱之间具有这种十分密切的关系,因此对洋底高原的研究将成为我们了解地球内部的窗口。以ODP对翁通-爪哇和凯尔盖朗（Kerguelen）海台的研究为例,简单介绍了洋底高原的基本特征、地幔柱在其形成过程中的作用以及目前在这一领域还未解决的一些问题。     

易自燃煤层综采工作面回采期间防灭火技术研究

宁夏灵武矿区所采煤层均属易自燃煤层,矿区煤炭自燃防治形势严峻.常规的注水、灌浆、注阻化剂灭火、氮气防灭火难以有效达到矿井防灭火要求.针对以上难题,以灵武矿区枣泉煤矿为例,分析了工作面开采期间的CO气体产生机理,据此提出了煤自燃火灾预防及治理技术思路.通过胶体隔离带的注胶防灭火技术手段,防灭火效果显著,工作面CO的的体积分数持续下降(＜6×10-6),有效得保证了矿井的安全生产.