Residential planning,driver mobility and CO2 emission: a microscopic look at Borlänge in Sweden

In a city there are hotspots that attract citizens, and most of the transportation arises when citizens move between their residence and primary destinations (i.e. hotspots). However, an ex ante evaluation of energy-efficient mobility and urban residential planning has seldom been conducted. Therefore, this paper proposes an ex ante evaluation method to quantify the impacts, in terms of CO₂ emissions induced by intra-urban car mobility, of residential plans for various urban areas. The method is illustrated in a case study of a Swedish midsize city, which is presently preoccupied with urban planning of new residential areas in response to substantial population growth due to immigration. In general, CO₂ emissions increase from the continued urban core area (CUCA), to the sub-polycentric area (SPA), to the edge urbanization area (EUA), where CO₂ emission of EUA is twice that of the CUCA. The average travel distances also increase in the same pattern, though the relative increase is more than four times. Apartment buildings could be more effective in meeting residential needs and mitigating CO₂ emissions than dispersed single-family houses.     

Substitute or addition to hypermobile lifestyles? Second home mobility and Finnish CO2 emissions

Tourism produces an increasing share in global greenhouse gas (GHG) emissions. These are mostly derived from transport emissions, and long-haul air travel in particular. Short-haul domestic tourism is believed by some to be a potential substitute for long-haul tourism. Using the example of Finland this paper examines the extent to which domestic second home tourism can substitute for other leisure trips and therefore contribute to reductions of travel-generated GHG emissions. Survey data are used to evaluate the CO₂ emissions caused by travel to domestic second homes, and to create statistical models that verify if the owners of domestic second homes travel to other leisure destinations less frequently than others, and if they cause less emissions by their leisure mobility than others with comparable economic and demographic background. We find that although the owners and users of domestic second homes travel for other leisure purposes less frequently than others, this does not mean their leisure mobility generates less emissions. Overall, owners of second homes produce significantly more CO₂ by their leisure mobility than non-owners. The use of second homes does not seem to be a substitute for high emission long-haul travels, but rather a part of an overall highly mobile leisure lifestyle. It is therefore necessary to better understand and influence the entire range of individual mobility behaviours in order to reduce travel-related GHG emissions.     

The Effects of Climate and Socio‐Demographics on Direct Household Carbon Dioxide Emissions in Australia

Household CO₂ emissions are a significant contributor to global greenhouse gas emissions and consequently climate warming. Despite this, there has been little consideration of how household CO₂ emissions may be affected by changes in climate. The aim of the present study has been to investigate the way climate, as well as socio‐demographic characteristics, may affect household CO₂ emissions produced from energy use. A national online survey was conducted to determine current household CO₂ emissions in Australia as well as capture the ownership and use of household appliances and installations. Electricity and gas‐based emissions as well as the ownership of a variety of household appliances and installations were found to be strongly associated with temperature. Electricity and gas emissions were found to decrease as annual average temperatures increase. However, as temperatures continue to rise under climate change this pattern may be reversed owing to increased reliance on air conditioners. One option for preventing this from occurring is to encourage houses to adopt more solar‐passive installations. Although this may be expensive, households with higher emissions tend to have higher incomes, indicating that they may have the capacity to pay for such installations.     

LIVING MATTER AND TERRESTRIAL GLACIATION

Paleogeographic reconstructions and forecasts of climatic change have been based largely on the impact of cosmic and astronomic factors and have tended to ignore the impact of the geochemical activity of living organisms. Yet the CO₂ cycle in the biosphere (volcanic emissions on the income side and photosynthesis and burial of dead organic matter on the outgo side) can have a significant impact on climatic change because of the greenhouse effect. The CO₂ theory is used to explain the sequence of glacial and interglacial stages of the Pleistocene. Active volcanism during the Alpine mountain-building period resulted in a high CO₂ content in the atmosphere fostering the building up of a large phytomass. The continued absorption of CO₂ produced a cooling trend that led to the Ice Age. The spread of the ice sheet reduced the terrestrial biomass and thus the rate of CO₂ absorption, resulting in an increase of CO₂ in the atmosphere and a warming trend. In the interglacial stage that followed, the build-up of biomass again reduced atmospheric CO₂, producing a new cooling trend. This natural glacial-interglacial rhythm has been modified in the last 5,000 years by human activity. Maninduced reduction of phytomass (through deforestation) and, more recently, the intensive combustion of fossil fuels tend to increase the CO₂ content of the atmosphere (in contrast to the natural interglacial process) and make the advent of a new glacial stage unlikely. (The article was contributed by Victor L. Mote, University of Houston.)     

Thermal effects on cathodoluminescence in forsterite

Cathodoluminescence (CL) spectral analysis has been conducted for luminescent forsterite (olivine) of terrestrial and meteoritic origins. Two emission bands at 3.15 and 2.99 eV in blue region can be assigned to structural defect centres and two emission bands at 1.91 and 1.74 eV in red region to impurity centres of Mn²⁺ and Cr³⁺, respectively. These emissions reduce their intensities at higher temperature, suggesting a temperature quenching phenomenon. The activation energy in the quenching process was estimated by a least-square fitting of the Arrhenius plots using integrated intensity of each component as follows; blue emissions at 3.15 eV: 0.08–0.10 eV and at 2.99 eV: 0.09–0.11 eV, red emissions at 1.91 eV: ～0.01 eV and at 1.74 eV: ～0.02 eV. The quenching process can be construed by the non-radiative transition by assuming the Mott-Seitz model. The values of activation energies for blue emissions caused by structural defects correspond to the vibration energy of Si-O stretching mode in the lattice, and the values for red emissions caused by Mn and Cr impurity centres to Mg-O vibration energy. It implies that the temperature quenching energy might be transferred as a phonon to the specific lattice vibration.     

Geodynamically induced variations in the emission of CO2 gas at San Faustino (Central Apennines,Italy)

The Central Apennines are affected by frequent earthquakes of moderate magnitude that occur mainly within the upper part of the crust at depths of <15 km. A large number of cold gas emissions that are rich in CO₂ are also found in the region. One particular vent with a high rate of degassing was equipped with a sensor to measure flow rates, which were recorded for a number of different periods between 2005 and 2010. Factors that could affect potentially CO₂ flow rates include barometric pressure, atmospheric temperature, precipitation and local seismicity. Our analysis indicates that the periods of anomalous flow rate were related not to the environmental factors but probably to the deformative processes of the crust associated with the local seismicity. Local seismic events as expression of geodynamic processes occurred always before and during these anomalous gas flow periods. This correlation exists only for events that occurred eastwards of the gas emission site close to the Martana fault zone. We herein consider this correlation as indication for a continuous interaction between the field of static strain and the deep fluid pressure. An approximation of the fluid pressure transmission towards the gas emission site gives reasonable values of 1–10 m² sec^?1. To make comparisons with the long‐term effects of the static strain, we also recorded the short‐term effects of the dynamic release of strain induced by the series of strong earthquakes that took place in L’Aquila in 2009. We detected a significant anomalous flow rate that occurred at the same time as this seismic sequence, during which widespread degassing was induced around the focal zone.     

Labour Productivity and Energy Use in a Three‐Sector Model: An Application to Egypt

This article presents a model of a developing economy with three sectors — industry, agriculture and energy. Industry and energy are assumed to be demand‐constrained, but agriculture supply‐constrained. The model highlights: (a) structural transformation, through labour transfer from agriculture to industry; (b) inflation, driven by the interaction of demand and the supply constraint in agriculture; and (c) the link between energy use and labour productivity. Employing a Kaldor‐Verdoorn productivity rule in industry augmented with energy intensity — energy per unit of labour — as an argument, we emphasize that labour productivity growth is driven by energy intensity rather than energy productivity growth. As a consequence, emissions reduction without North–South technology transfer and financial assistance costs growth.     

Decreasing CO2 partial pressure triggered Mg–Fe–Ca carbonate formation in ancient Martian crust preserved in the ALH84001 Meteorite

We retrace hydrogeochemical processes leading to the formation of Mg–Fe–Ca carbonate concretions (first distinct carbonate population, FDCP) in Martian meteorite ALH84001 by generic hydrogeochemical equilibrium and mass transfer modeling. Our simple conceptual models assume isochemical equilibration of orthopyroxenite minerals with pure water at varying water‐to‐rock ratios, temperatures and CO₂ partial pressures. Modeled scenarios include CO₂ partial pressures ranging from 10.1325 to 0.0001 MPa at water‐to‐rock ratios between 4380 and 43.8 mol mol^?1 and different temperatures (278, 303 and 348 K) and enable the precipitation of Mg–Fe–Ca solid solution carbonate. Modeled range and trend of carbonate compositional variation from magnesio‐siderite (core) to magnesite (rim), and the precipitation of amorphous SiO₂ and magnetite coupled to magnesite‐rich carbonate are similar to measured compositional variation. The results of this study suggest that the early Martian subsurface had been exposed to a dynamic gas pressure regime with decreasing CO₂ partial pressure at low temperatures (approximately 1.0133 to 0.0001 MPa at 278 K or 6 to 0.0001 MPa at 303 K). Moderate water‐to‐rock ratios of ca. 438 mol mol^?1 and isochemical weathering of orthopyroxenite are additional key prerequisites for the formation of secondary phase assemblages similar to ALH84001’s ‘FDCP’. Outbursts of water and CO_2(g) from confined ground water in fractured orthopyroxenite rocks below an unstable CO₂ hydrate‐containing cryosphere provide adequate environments on the early Martian surface.     

IDENTIFYING OPTIMAL SECTOR GROUPINGS WITH THE HYPOTHETICAL EXTRACTION METHOD*

ABSTRACT We formulate the problems of finding a key sector and a key group of sectors in the economy by the hypothetical extraction method (HEM), and derive their analytic solutions that are termed industries’ factor worths. It is shown that the key group of k ≥ 2 sectors is, in general, different from the set of top k industries selected on the basis of the key sector problem, the issue which is totally ignored in the input–output (IO) linkage literature. Further, the related problems of finding a key region and a key group of regions in an interregional IO setting are discussed. We also examine how a change in an input coefficient affects the factor worth of an industry. The key group problem is applied to the Australian economy for factors of water use, CO₂ emissions, and generation of profits and wages.     

Hydrogen and Fuel Cell Development in China: A Review

Hydrogen and fuel cells may have a major role in the future energy market if governments give a high priority to reduction of CO₂ emissions with associated R&D investment in efficient hydrogen technologies. It is predicted that China would have the highest share of hydrogen fuel cell vehicles in 2050 if their ambitious climate and energy security policies are adopted (OECD (Organisation for Economic Co-operation and Development)/IEA (International Energy Agency) (2005) Prospects for Hydrogen and Fuel Cells (Paris: OECD Publications)). R&D in hydrogen and fuel cell technologies in China has been pushed by the central government's commitment to reduce air pollution emissions from transportation, to enhance energy security and improve national competitiveness. The paper focuses on current policies and progress on hydrogen and fuel cell development in China. Development prospects and challenges are discussed with a view to achieving better understanding of the emerging hydrogen economy.     

Tectonic control over large-scale diffuse degassing in eastern Sicily (Italy)

Eastern Sicily (southern Italy) is characterised by the presence of many natural gas emissions (mofettes, mud volcanoes). These gases are mostly carbon dioxide and methane, with minor amounts of helium, hydrogen, carbon monoxide and hydrocarbons. In this study, the extent and orientation of soil gas anomalies (He and CO₂) were investigated on a wide area (approximately 110 km²) located just SW of Mt. Etna. From a structural point of view, this area lays on a typical foredeep–foreland system that marks the boundary between the southern part of the Eurasian plate and the northern part of the African plate in the central Mediterranean. No tectonic structure was revealed in this area by surface geological surveys. Very high soil emissions were found, and their spatial pattern reveals the existence of some active faults all directed about N50°E. This direction coincides with that of two major fault systems that cut eastern Sicily and are evident, respectively, NE and SW of the study area. Soil gas data suggest that these fault systems are the expression of a single continuous structural line which is probably responsible for the past and present magma uprise in eastern Sicily. Isotopic values of carbon of CO₂ suggest a minor contribution of organic carbon. Moreover, in the highest degassing sites the isotopic values of He found in association with CO₂ (He abundance = 11–70 p.p.m.; R/R_a between 6.0 and 6.2) suggest that both gases are mantle derived. The extent of the areas affected by high gas emissions and the amounts of deep CO₂ emitted in the investigated area (several hundred tonnes per day) may provide additional supporting evidence of a mantle upwelling taking place beneath this region.     

Study of coal gas wettability for CO2 storage and CH4 recovery

To quantify and rank gas wettability of coal as a key parameter affecting the extent of CO₂ sequestration in coal and CH₄ recovery from coal, we developed a contact angle measuring system based on a captive gas bubble technique. We used this system to study the gas wetting properties of an Australian coal from the Sydney Basin. Gas bubbles were generated and captivated beneath a coal sample within a distilled water‐filled (pH 5.7) pressurised cell. Because of the use of distilled water, and the continuous dissolution and shrinkage of the gas bubble in water during measurement, the contact angles measured correspond to a ‘transient receding’ contact angle. To take into account the mixed‐gas nature (CO₂, CH₄, and to a lesser extent N₂) of coal seam gas in the basin, we evaluated the relative wettability of coal by CH₄, CO₂ and N₂ gases in the presence of water. Measurements were taken at various pressures of up to 15 MPa for CH₄ and N₂, and up to 6 MPa for CO₂ at a constant temperature of 22°C. Overall, our results show that CO₂ wets coal more extensively than CH₄, which in turn wets coal slightly more than N₂. Moreover, the contact angle reduces as the pressure increases, and becomes < 90° at various pressures depending on the gas type. In other words, all three gases wet coal better than water under sufficiently high pressure.     

Radiocarbon method in monitoring of fossil fuel emission

The traditional radiocarbon method widely used in archaeology and geology for chronological purposes can also be used in environmental studies. Combustion of fossil fuels like coal, natural gas, petroleum, etc., in industrial and/or heavily urbanized areas, has increased the concentration of carbon dioxide in the atmosphere. The addition of fossil carbon caused changes of carbon isotopic composition, in particular, a definite decrease of ¹⁴C concentration in atmospheric CO₂ and other carbon reservoirs (ocean and terrestrial biosphere), known as the Suess effect. Tree rings, leaves, as well as other annual growing plants reflected the changes of radiocarbon concentration in the atmosphere due to processes of photosynthesis and assimilation of carbon from the air. By measuring radiocarbon concentration directly in atmospheric CO₂ samples and/or biospheric material growing in industrial and/or highly urbanized areas where high emission of dead carbon is expected, it is possible to estimate the total emission of dead CO₂. Based on equations of mass balance for CO₂ concentration, stable isotopic composition of carbon and radiocarbon concentration it is possible to calculate CO₂ con-centration associated with fossil fuel emission into the atmosphere. The procedure use differences between the radiocarbon concentration and stable isotope composition of carbon observed in clean areas and industrial or/and highly urbanized areas.     

Response of cathodoluminescence of alkali feldspar to He+ ion implantation and electron irradiation

Cathodoluminescence (CL) of minerals such as quartz and zircon has been extensively studied to be used as an indicator for geodosimetry and geochronometry. There are, however, very few investigations on CL of other rock-forming minerals such as feldspars, regardless of their great scientific interest. This study has sought to clarify the effect of He+ ion implantation and electron irradiation on luminescent emissions by acquiring CL spectra from various types of feldspars including anorthoclase, amazonite and adularia. CL intensities of UV and blue emissions, assigned to Pb²⁺ and Ti⁴⁺ impurity centers respectively, decrease with an increase in radiation dose of He⁺ ion implantation and electron irradiation time. This may be due to decrease in the luminescence efficiencies by a change of the activation energy or a conversion of the emission center to a non-luminescent center due to an alteration of the energy state. Also, CL spectroscopy of the alkali feldspar revealed an in-crease in the blue and yellow emission intensity assigned to Al-O^?-Al/Ti defect and radiation-induced defect centers with the radiation dose and the electron irradiation time. Taken together these results indicate that CL signal should be used for estimation of the α and β radiation doses from natural radionuclides that alkali feldspars have experienced.     

Characteristics of CO2‐driven cold‐water geyser,Crystal Geyser in Utah: experimental observation and mechanism analyses

Geologic carbon capture and storage (CCS) is an option for reducing CO₂ emissions, but leakage to the surface is a risk factor. Natural CO₂ reservoirs that erupt from abandoned oil and gas holes leak to the surface as spectacular cold geysers in the Colorado Plateau, United States. A better understanding of the mechanisms of CO₂‐driven cold‐water geysers will provide valuable insight about the potential modes of leakage from engineered CCS sites. A notable example of a CO₂‐driven cold‐water geyser is Crystal Geyser in central Utah. We investigated the fluid mechanics of this regularly erupting geyser by instrumenting its conduit with sensors and measuring pressure and temperature every 20 sec over a period of 17 days. Analyses of these measurements suggest that the timescale of a single‐eruption cycle is composed of four successive eruption types with two recharge periods ranging from 30 to 40 h. Current eruption patterns exhibit a bimodal distribution, but these patterns evolved during past 80 years. The field observation suggests that the geyser's eruptions are regular and predictable and reflect pressure and temperature changes resulting from Joule–Thomson cooling and endothermic CO₂ exsolution. The eruption interval between multiple small‐scale eruptions is a direct indicator of the subsequent large‐scale eruption.     

Infrared radiative cooling in the mesosphere and lower thermosphere

This paper discusses the current status of calculating infrared cooling by CO₂ in the mesosphere and lower thermosphere. It is desirable to have fast but accurate procedures for use in dynamic models. The most difficult region is from 70 to 90 km, where cooling rates are strongly influenced or, in the case of the summer mesopause region, dominated by the absorption of radiation emitted by underlying layers, with the hot bands and isotopic bands playing a significant role. A three-energy-level model is derived for the excited population levels of a CO₂ molecule. Vibrational-vibrational coupling between isotopes is also included as significant. Results from model calculations for cooling rates and NLTE source functions are presented. Global average infrared cooling rates appear to be in reasonable balance with solar heating rates, considering the uncertainties in calculating both these terms. Radiative cooling rates by CO₂ above 100 km are strongly dependent on atomic oxygen concentrations and on the rate of energy exchange between atomic oxygen and CO₂. Likewise, NO cooling, which is important above 120 km, is proportional to atomic oxygen concentrations. Since CO₂, NO and O concentrations can all vary with motions, these dependencies suggest interesting feedbacks to atmospheric dynamics.     

旅游业碳排放强度分布及其驱动因子的时空异质研究——基于30个省(市、区)2005-2014年的面板数据分析

本文利用交通运输业、邮电业、商业、餐饮业、住宿业以及社会服务业这6个行业面板数据,在揭示2005年至2014年30个省(市、区)旅游业碳排放总量与强度的时空动态变化关系时,借助LMDI法分解出影响我国旅游业碳排放增加量的关键因素。研究结果表明:①旅游业碳排放总量在时间上呈逐年上升趋势,且中、西部地区增长速度要显著高于东部地区;②旅游业碳排放强度在时间上呈逐年递减趋势,且中、西部地区下降速度要显著低于东部地区;③影响我国旅游业碳排放增加量的关键因素取决于经济产出因子(TEO)、接待人次因子(TP)、行业结构因子(TIS)、能源效率因子(TEE)、能源结构因子(TES)5个方面,前两者为增量因子,后三者为减量因子。     

Observation and analysis of NI 520.0 nm auroral emissions

The results from the analysis of simultaneous auroral ground-based optical measurements of the N(²D) 520.0 nm, N₂⁺ 1NG 470.9 nm, O(³P) 844.6 nm and the O(¹D) 630.0 nm emission intensities are presented. The data were obtained during auroral observations at Gillam (56.35°N, 265.32°E) over an observation period of about 8 hours, from UT 2:33 hrs to UT 10:06 hrs, on 20 March 1985. The soft electron flux measurements on board the DMSP satellite for the time of the experiment have also been considered in the analysis. The N(²D) density and the N(²D) 520.0 nm integral emission rate I(520.0) were calculated employing a one- and two-dimensional time-dependent ion-chemistry model and the model predictions have been compared with the experimental I(520.0) nm emission rates. It was found that the model predictions of the NI I(520.0) nm intensity based on the electron energy fluxes inferred from the experimental I(844.6)/I(427.8) emission rate ratios are smaller in magnitude than the experimental values by a factor of 5–8 after allowing for horizontal transport of [N(²D)] by neutral winds. Assuming soft electron precipitation, suggested by the OI I(630.0) nm emission measurements and the DMSP satellite electron flux data, provided good agreement between the model and experimental results. Based on the results obtained it was concluded that horizontal transport played a minor role and that the observed N(²D) I(520.0) nm emissions were mostly produced by precipitating soft electron fluxes with energies below about 100 eV.     

Observations of gravity waves from multispectral mesospheric nightglow emissions observed at 23°S

Simultaneous measurements of the 015 57.7 nm, O₂ atmospheric (0,1) band, NaD and OH (9,4) band emissions obtained during the period October November 1989 at Cachoeira Paulista (23°S, 45°W), Brazil, have been analysed to study gravity waves in the mesospheric region at a low-latitude station in the southern hemisphere. It was found that, when these emissions showed large temporal intensity variations, there were also short period quasi-coherent temporal variations superposed on them, suggesting a possible passage of internal gravity waves in the emission layers. Cross-correlation analysis indicates that the time lag between the different emissions is smaller for short period variations compared with the long period variations. The wave parameters, namely a vertical wavelength of 12 km, a horizontal derived wavelength of 200 km with a period of 80 min, estimated from one of the observed short-period coherent oscillations, are typical of the internal gravity waves at the airglow emission height.     

REGULATORY FEDERALISM AND THE DISTRIBUTION OF AIR POLLUTANT EMISSIONS*

ABSTRACT Recent empirical work suggests that (i) incomes are converging through time, and (ii) income and pollution levels are linked. This paper weds these two literatures by examining the spatial and temporal distribution of pollution. After establishing that theoretical predictions about whether pollution will converge are critically linked to certain structural parameters, we explore pollution convergence using state‐level data on two important pollutants—nitrogen oxides and sulfur oxides—from 1929 to 1999. We find stronger evidence of converging emission rates during the federal pollution control years (1970–1999) than during the local control years (1929–1969). These results suggest that income convergence alone may not be sufficient to induce convergence of pollutant emissions.