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Greenhouse Gas (greenhouse + gas)
Terms modified by Greenhouse Gas Selected AbstractsAccurate correlations to estimate refinery fuel gas, natural gas, and fuel oil CO2 emission factors and its uncertaintyAICHE JOURNAL, Issue 9 2010Esteban F. Mįrquez-Riquelme Abstract The quantification of Greenhouse Gas (GHG) inventories and its associated uncertainty is a relevant activity often requested by authorities. Accurate methods to calculate both inventories and the involved uncertainty are convenient for close monitoring purposes. Using Monte Carlo simulations, correlations of high accuracy between emission factors (EFs), lower heating value (LHV), and density were built for refinery fuel gas, natural gas and fuel/residual oil. In all cases, the data generated by the simulations also served the purpose of building correlations for upper and lower bounds of the EF that can be readily used to estimate the EF estimation uncertainty. The correlations were tested against actual refinery data and the results show that more accurate estimations were obtained compared with EF obtained from laboratory composition methods and from methods that estimate EF as proportional to LHV only. In the case of fuel and residual oils, the correlations developed are a function of LHV only but were improved by using a cubic polynomial. The calculation of upper and lower bounds for EF offer a convenient method to estimate EF uncertainties that are required in official GHG emissions inventory calculations. In conclusion, in addition to LHV, the use of one additional readily available fuel property, namely fuel density is sufficient to reduce uncertainty of estimation of GHG (in this case CO2) from combustion to acceptable levels. © 2010 American Institute of Chemical Engineers AIChE J, 2010 [source] Greenhouse gas and groundwater recharge abatement benefits of tree crops in south-western Australian farming systemsAUSTRALIAN JOURNAL OF AGRICULTURAL & RESOURCE ECONOMICS, Issue 2 2003Elizabeth Petersen The indirect benefits of a commercial tree crop for greenhouse gas and groundwater recharge abatement are analysed. Oil mallees are introduced into a whole-farm linear programming model as a source of income, an offset to greenhouse gas emissions from the mixed sheep and cropping enterprises and as a source of groundwater recharge abatement. The profitability of oil mallees is found to be very sensitive to the discount rate, yield and price assumptions and the relative profitability of other farm enterprises (especially the wool enterprise). Under standard assumptions where oil mallees are profitable, the trees significantly reduced greenhouse gas emissions and groundwater recharge and the farm remains profitable. If farm-level policies are introduced for greenhouse gas abatement, without tree crops or some other technological change, the current farming systems would fail and be replaced by alternative land uses. [source] Local authorities, climate change and small and medium enterprises: identifying effective policy instruments to reduce energy use and carbon emissionsCORPORATE SOCIAL RESPONSIBILITY AND ENVIRONMENTAL MANAGEMENT, Issue 3 2008Jaryn Bradford Abstract This paper discusses potential policy options available to local and municipal authorities, to achieve reductions in energy usage and greenhouse gas (GHG) emissions from small and medium-sized enterprises (SMEs). Researchers conducted surveys with 112 SMEs, and the results have been used to disaggregate the category of ,SME' into sub-sectors based on industrial sector, two measurements of employee size and annual turnover. A statistical analysis identifies key characteristics and behaviours of the sub-sectors of firms and discusses the type of policy measure these groups of SMEs would probably respond to. The key results of the research indicate that categories of firms differ in terms of energy use behaviours, internal constraints and attitudes toward possible policy options. The paper presents a ,policy matrix' to represent the most and least likely policy options to achieve energy savings from different categories of SMEs. Copyright © 2007 John Wiley & Sons, Ltd and ERP Environment. [source] Activity and composition of methanotrophic bacterial communities in planted rice soil studied by flux measurements, analyses of pmoA gene and stable isotope probing of phospholipid fatty acidsENVIRONMENTAL MICROBIOLOGY, Issue 2 2008Minita Shrestha Summary Methanotrophs in the rhizosphere of rice field ecosystems attenuate the emissions of CH4 into the atmosphere and thus play an important role for the global cycle of this greenhouse gas. Therefore, we measured the activity and composition of the methanotrophic community in the rhizosphere of rice microcosms. Methane oxidation was determined by measuring the CH4 flux in the presence and absence of difluoromethane as a specific inhibitor for methane oxidation. Methane oxidation started on day 24 and reached the maximum on day 32 after transplantation. The total methanotrophic community was analysed by terminal restriction fragment length polymorphism (T-RFLP) and cloning/sequencing of the pmoA gene, which encodes a subunit of particulate methane monooxygenase. The metabolically active methanotrophic community was analysed by stable isotope probing of microbial phospholipid fatty acids (PLFA-SIP) using 13C-labelled CH4 directly added to the rhizospheric region. Rhizospheric soil and root samples were collected after exposure to 13CH4 for 8 and 18 days. Both T-RFLP/cloning and PLFA-SIP approaches showed that type I and type II methanotrophic populations changed over time with respect to activity and population size in the rhizospheric soil and on the rice roots. However, type I methanotrophs were more active than type II methanotrophs at both time points indicating they were of particular importance in the rhizosphere. PLFA-SIP showed that the active methanotrophic populations exhibit a pronounced spatial and temporal variation in rice microcosms. [source] Comparison of greenhouse gas fluxes and nitrogen budgets from an ombotrophic bog in Scotland and a minerotrophic sedge fen in FinlandEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 5 2010J. Drewer Northern peatlands cover approximately 4% of the global land surface area. Those peatlands will be particularly vulnerable to environmental and climate change and therefore it is important to investigate their total greenhouse gas (GHG) budgets, to determine the feedback on the climate. Nitrogen (N) is known to influence the GHG budget in particular by affecting the methane (CH4) balance. At two peatland sites in Scotland and Finland GHG fluxes of carbon dioxide (CO2), methane and nitrous oxide (N2O) and nitrogen fluxes were measured as part of the European project ,NitroEurope'. The Scottish site, Auchencorth Moss, was a GHG sink of ,321, ,490 and ,321 g CO2 eq m,2 year,1 in 2006, 2007 and 2008, respectively, with CO2 as the dominating GHG. In contrast, the dominating GHG at the Finnish site, Lompolojänkkä, was CH4, resulting in the site being a net GHG source of +485 and +431 g CO2 eq m,2 year,1 in 2006 and 2007, respectively. Therefore, Auchencorth Moss had a negative global warming potential (GWP) whilst Lompolojänkkä had a positive GWP over the investigated time period. Initial results yielded a positive N budget for Lompolojänkkä of 7.1 kg N ha,1 year,1, meaning the site was gaining nitrogen, and a negative N budget for Auchencorth Moss of ,2.4 kg N ha year,1, meaning the site was losing nitrogen. [source] Nitrifier denitrification can be a source of N2O from soil: a revised approach to the dual-isotope labelling methodEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 5 2010D. M. Kool Nitrifier denitrification (i.e. nitrite reduction by ammonia oxidizers) is one of the biochemical pathways of nitrous oxide (N2O) production. It is increasingly suggested that this pathway may contribute substantially to N2O production in soil, the major source of this greenhouse gas. However, although monoculture studies recognize its potential, methodological drawbacks prohibit conclusive proof that nitrifier denitrification occurs in actual soils. Here we suggest and apply a new isotopic approach to identify its presence in soil. In incubation experiments with 12 soils, N2O production was studied using oxygen (O) and nitrogen (N) isotope tracing, accounting for O exchange. Microbial biomass C and N and phospholipid fatty acid (PLFA) patterns were analysed to explain potential differences in N2O production pathways. We found that in at least five of the soils nitrifier denitrification must have contributed to N2O production. Moreover, it may even have been responsible for all NH4+ -derived N2O in most soils. In contrast, N2O as a by-product of ammonia oxidation contributed very little to total production. Microbial biomass C and N and PLFA-distinguished microbial community composition were not indicative of differences in N2O production pathways. Overall, we show that combined O and N isotope tracing may still provide a powerful tool to understand N2O production pathways, provided that O exchange is accounted for. We conclude that nitrifier denitrification can indeed occur in soils, and may in fact be responsible for the greater proportion of total nitrifier-induced N2O production. [source] Atmospheric impact of bioenergy based on perennial crop (reed canary grass, Phalaris arundinaceae, L.) cultivation on a drained boreal organic soilGCB BIOENERGY, Issue 3 2010NARASINHA J. SHURPALI Abstract Marginal organic soils, abundant in the boreal region, are being increasingly used for bioenergy crop cultivation. Using long-term field experimental data on greenhouse gas (GHG) balance from a perennial bioenergy crop [reed canary grass (RCG), Phalaris arundinaceae L.] cultivated on a drained organic soil as an example, we show here for the first time that, with a proper cultivation and land-use practice, environmentally sound bioenergy production is possible on these problematic soil types. We performed a life cycle assessment (LCA) for RCG on this organic soil. We found that, on an average, this system produces 40% less CO2 -equivalents per MWh of energy in comparison with a conventional energy source such as coal. Climatic conditions regulating the RCG carbon exchange processes have a high impact on the benefits from this bioenergy production system. Under appropriate hydrological conditions, this system can even be carbon-negative. An LCA sensitivity analysis revealed that net ecosystem CO2 exchange and crop yield are the major LCA components, while non-CO2 GHG emissions and costs associated with crop production are the minor ones. Net bioenergy GHG emissions resulting from restricted net CO2 uptake and low crop yields, due to climatic and moisture stress during dry years, were comparable with coal emissions. However, net bioenergy emissions during wet years with high net uptake and crop yield were only a third of the coal emissions. As long-term experimental data on GHG balance of bioenergy production are scarce, scientific data stemming from field experiments are needed in shaping renewable energy source policies. [source] Greenhouse gas emissions from four bioenergy crops in England and Wales: Integrating spatial estimates of yield and soil carbon balance in life cycle analysesGCB BIOENERGY, Issue 4 2009JONATHAN HILLIER Abstract Accurate estimation of the greenhouse gas (GHG) mitigation potential of bioenergy crops requires the integration of a significant component of spatially varying information. In particular, crop yield and soil carbon (C) stocks are variables which are generally soil type and climate dependent. Since gaseous emissions from soil C depend on current C stocks, which in turn are related to previous land management it is important to consider both previous and proposed future land use in any C accounting assessment. We have conducted a spatially explicit study for England and Wales, coupling empirical yield maps with the RothC soil C turnover model to simulate soil C dynamics. We estimate soil C changes under proposed planting of four bioenergy crops, Miscanthus (Miscanthus×giganteus), short rotation coppice (SRC) poplar (Populus trichocarpa Torr. & Gray ×P. trichocarpa, var. Trichobel), winter wheat, and oilseed rape. This is then related to the former land use , arable, pasture, or forest/seminatural, and the outputs are then assessed in the context of a life cycle analysis (LCA) for each crop. By offsetting emissions from management under the previous land use, and considering fossil fuel C displaced, the GHG balance is estimated for each of the 12 land use change transitions associated with replacing arable, grassland, or forest/seminatural land, with each of the four bioenergy crops. Miscanthus and SRC are likely to have a mostly beneficial impact in reducing GHG emissions, while oilseed rape and winter wheat have either a net GHG cost, or only a marginal benefit. Previous land use is important and can make the difference between the bioenergy crop being beneficial or worse than the existing land use in terms of GHG balance. [source] Assessment of methane and nitrous oxide flux from mangroves along Eastern coast of IndiaGEOFLUIDS (ELECTRONIC), Issue 4 2008R. CHAUHAN Abstract Mangroves are considered to be a minor source of greenhouse gases (CH4 and N2O) in pristine environmental condition. However, estimates of efflux suggest that anthropogenic activities have led to a pronounced increase in greenhouse gas emission. Along the east coast of India, mangroves vary substantially in area, physiography and freshwater input, which ultimately modify the biogeochemical processes operating within this ecosystem. An attempt has here been made to elucidate the existing variation and role of climatic variability on the emission of greenhouse gases from mangroves. The flux estimates of CH4 and N2O have been quantified from Bhitarkanika mangrove accounting for spatial and temporal (seasonal) variation. The annual rates were estimated to be 0.096 × 10 9 g CH4 year,1 and 5.8 × 103g N2O year,1 for the whole mangrove area of the east coast of India. Upscaling these estimates yield an annual emission of 1.95 × 10 12 g CH4 year,1 and 1.1 × 10 11 g N2O year,1 from worldwide mangrove areas. The influence of elevated nutrient inputs through anthropogenic influence enhances the emission of greenhouse gas. The present article shows the need to develop an inventory on greenhouse gas flux from mangrove ecosystem. [source] The European carbon balance.GLOBAL CHANGE BIOLOGY, Issue 5 2010Part 2: croplands Abstract We estimated the long-term carbon balance [net biome production (NBP)] of European (EU-25) croplands and its component fluxes, over the last two decades. Net primary production (NPP) estimates, from different data sources ranged between 490 and 846 gC m,2 yr,1, and mostly reflect uncertainties in allocation, and in cropland area when using yield statistics. Inventories of soil C change over arable lands may be the most reliable source of information on NBP, but inventories lack full and harmonized coverage of EU-25. From a compilation of inventories we infer a mean loss of soil C amounting to 17 g m,2 yr,1. In addition, three process-based models, driven by historical climate and evolving agricultural technology, estimate a small sink of 15 g C m,2 yr,1 or a small source of 7.6 g C m,2 yr,1. Neither the soil C inventory data, nor the process model results support the previous European-scale NBP estimate by Janssens and colleagues of a large soil C loss of 90 ± 50 gC m,2 yr,1. Discrepancy between measured and modeled NBP is caused by erosion which is not inventoried, and the burning of harvest residues which is not modeled. When correcting the inventory NBP for the erosion flux, and the modeled NBP for agricultural fire losses, the discrepancy is reduced, and cropland NBP ranges between ,8.3 ± 13 and ,13 ± 33 g C m,2 yr,1 from the mean of the models and inventories, respectively. The mean nitrous oxide (N2O) flux estimates ranges between 32 and 37 g C Eq m,2 yr,1, which nearly doubles the CO2 losses. European croplands act as small CH4 sink of 3.3 g C Eq m,2 yr,1. Considering ecosystem CO2, N2O and CH4 fluxes provides for the net greenhouse gas balance a net source of 42,47 g C Eq m,2 yr,1. Intensifying agriculture in Eastern Europe to the same level Western Europe amounts is expected to result in a near doubling of the N2O emissions in Eastern Europe. N2O emissions will then become the main source of concern for the impact of European agriculture on climate. [source] Contribution of N2O to the greenhouse gas balance of first-generation biofuelsGLOBAL CHANGE BIOLOGY, Issue 1 2009EDWARD M. W. SMEETS Abstract In this study, we analyze the impact of fertilizer- and manure-induced N2O emissions due to energy crop production on the reduction of greenhouse gas (GHG) emissions when conventional transportation fuels are replaced by first-generation biofuels (also taking account of other GHG emissions during the entire life cycle). We calculate the nitrous oxide (N2O) emissions by applying a statistical model that uses spatial data on climate and soil. For the land use that is assumed to be replaced by energy crop production (the ,reference land-use system'), we explore a variety of options, the most important of which are cropland for food production, grassland, and natural vegetation. Calculations are also done in the case that emissions due to energy crop production are fully additional and thus no reference is considered. The results are combined with data on other emissions due to biofuels production that are derived from existing studies, resulting in total GHG emission reduction potentials for major biofuels compared with conventional fuels. The results show that N2O emissions can have an important impact on the overall GHG balance of biofuels, though there are large uncertainties. The most important ones are those in the statistical model and the GHG emissions not related to land use. Ethanol produced from sugar cane and sugar beet are relatively robust GHG savers: these biofuels change the GHG emissions by ,103% to ,60% (sugar cane) and ,58% to ,17% (sugar beet), compared with conventional transportation fuels and depending on the reference land-use system that is considered. The use of diesel from palm fruit also results in a relatively constant and substantial change of the GHG emissions by ,75% to ,39%. For corn and wheat ethanol, the figures are ,38% to 11% and ,107% to 53%, respectively. Rapeseed diesel changes the GHG emissions by ,81% to 72% and soybean diesel by ,111% to 44%. Optimized crop management, which involves the use of state-of-the-art agricultural technologies combined with an optimized fertilization regime and the use of nitrification inhibitors, can reduce N2O emissions substantially and change the GHG emissions by up to ,135 percent points (pp) compared with conventional management. However, the uncertainties in the statistical N2O emission model and in the data on non-land-use GHG emissions due to biofuels production are large; they can change the GHG emission reduction by between ,152 and 87 pp. [source] Soil greenhouse gas fluxes and global warming potential in four high-yielding maize systemsGLOBAL CHANGE BIOLOGY, Issue 9 2007M. A. A. ADVIENTO-BORBE Abstract Crop intensification is often thought to increase greenhouse gas (GHG) emissions, but studies in which crop management is optimized to exploit crop yield potential are rare. We conducted a field study in eastern Nebraska, USA to quantify GHG emissions, changes in soil organic carbon (SOC) and the net global warming potential (GWP) in four irrigated systems: continuous maize with recommended best management practices (CC-rec) or intensive management (CC-int) and maize,soybean rotation with recommended (CS-rec) or intensive management (CS-int). Grain yields of maize and soybean were generally within 80,100% of the estimated site yield potential. Large soil surface carbon dioxide (CO2) fluxes were mostly associated with rapid crop growth, high temperature and high soil water content. Within each crop rotation, soil CO2 efflux under intensive management was not consistently higher than with recommended management. Owing to differences in residue inputs, SOC increased in the two continuous maize systems, but decreased in CS-rec or remained unchanged in CS-int. N2O emission peaks were mainly associated with high temperature and high soil water content resulting from rainfall or irrigation events, but less clearly related to soil NO3 -N levels. N2O fluxes in intensively managed systems were only occasionally greater than those measured in the CC-rec and CS-rec systems. Fertilizer-induced N2O emissions ranged from 1.9% to 3.5% in 2003, from 0.8% to 1.5% in 2004 and from 0.4% to 0.5% in 2005, with no consistent differences among the four systems. All four cropping systems where net sources of GHG. However, due to increased soil C sequestration continuous maize systems had lower GWP than maize,soybean systems and intensive management did not cause a significant increase in GWP. Converting maize grain to ethanol in the two continuous maize systems resulted in a net reduction in life cycle GHG emissions of maize ethanol relative to petrol-based gasoline by 33,38%. Our study provided evidence that net GHG emissions from agricultural systems can be kept low when management is optimized toward better exploitation of the yield potential. Major components for this included (i) choosing the right combination of adopted varieties, planting date and plant population to maximize crop biomass productivity, (ii) tactical water and nitrogen (N) management decisions that contributed to high N use efficiency and avoided extreme N2O emissions, and (iii) a deep tillage and residue management approach that favored the build-up of soil organic matter from large amounts of crop residues returned. [source] Soil-atmospheric exchange of CO2, CH4, and N2O in three subtropical forest ecosystems in southern ChinaGLOBAL CHANGE BIOLOGY, Issue 3 2006XULI TANG Abstract The magnitude, temporal, and spatial patterns of soil-atmospheric greenhouse gas (hereafter referred to as GHG) exchanges in forests near the Tropic of Cancer are still highly uncertain. To contribute towards an improvement of actual estimates, soil-atmospheric CO2, CH4, and N2O fluxes were measured in three successional subtropical forests at the Dinghushan Nature Reserve (hereafter referred to as DNR) in southern China. Soils in DNR forests behaved as N2O sources and CH4 sinks. Annual mean CO2, N2O, and CH4 fluxes (mean±SD) were 7.7±4.6 Mg CO2 -C ha,1 yr,1, 3.2±1.2 kg N2O-N ha,1 yr,1, and 3.4±0.9 kg CH4 -C ha,1 yr,1, respectively. The climate was warm and wet from April through September 2003 (the hot-humid season) and became cool and dry from October 2003 through March 2004 (the cool-dry season). The seasonality of soil CO2 emission coincided with the seasonal climate pattern, with high CO2 emission rates in the hot-humid season and low rates in the cool-dry season. In contrast, seasonal patterns of CH4 and N2O fluxes were not clear, although higher CH4 uptake rates were often observed in the cool-dry season and higher N2O emission rates were often observed in the hot-humid season. GHG fluxes measured at these three sites showed a clear increasing trend with the progressive succession. If this trend is representative at the regional scale, CO2 and N2O emissions and CH4 uptake in southern China may increase in the future in light of the projected change in forest age structure. Removal of surface litter reduced soil CO2 effluxes by 17,44% in the three forests but had no significant effect on CH4 absorption and N2O emission rates. This suggests that microbial CH4 uptake and N2O production was mainly related to the mineral soil rather than in the surface litter layer. [source] Implications of climate change for grassland in Europe: impacts, adaptations and mitigation options: a reviewGRASS & FORAGE SCIENCE, Issue 2 2007A. Hopkins Summary Climate change associated with greenhouse gas (GHG) emissions may have important implications for Europe's grasslands. Projected scenarios indicate that increased temperatures and CO2 concentrations have the potential to increase herbage growth and to favour legumes more than grasses, but changes in seasonal precipitation would reduce these benefits particularly in areas with low summer rainfall. Further implications for grasslands may arise from increased frequency of droughts, storms and other extreme events. Potential farm-scale adaptive responses to climate change are identified. Grassland agriculture also contributes to GHG emissions, particularly methane and nitrous oxide, and management of grassland affects net carbon balances and carbon sequestration. Management options are identified for mitigating grassland's contribution to GHG emissions which need to be developed in a holistic way that also considers other pressures. [source] Dynamic operation plan of a combined fuel cell cogeneration, solar module, and geo-thermal heat pump system using Genetic AlgorithmINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 13 2007Shin'ya Obara Abstract A chromosome model that simulates the operation patterns of an energy system was introduced into a simple Genetic Algorithm, and a method of dynamic optimization was developed. This paper analyses the operation planning of an energy system that uses in combination a solar power module, proton-exchange membrane fuel cell cogeneration (PEMFC-CGS) with methanol steam reforming, a geo-thermal heat pump, heat storage and battery, commercial power, and a kerosene boiler. The hours of operation of each energy device and the rate of the energy output were calculated by having introduced the analysis program developed by this study. Three objective functions: (a) minimization of operation cost; (b) minimization of the error of demand-and-supply balance; and (c) minimization of the amount of greenhouse gas discharge were given to the optimization analysis of the system. Furthermore, the characteristics of the system operation planning under each objective function are described. Copyright © 2007 John Wiley & Sons, Ltd. [source] Greenhouse gas reduction potential of advanced traffic controlJOURNAL OF ADVANCED TRANSPORTATION, Issue 3 2000Abdulkader Alkadry Reducing greenhouse gas (GHG) emissions from transportation in the context of the climate change issue and the associated Kyoto Agreement of 1997 is a challenge. Since urban transportation is a major contributor to greenhouse gases, measures are required to reduce these emissions. Given that during peak periods, road vehicles propelled by petroleum fuel-based internal combustion engines produce a high level of GHG emissions due to stop and go operations, measures to improve traffic flow can play an effective mitigation role. This paper describes a simulation-based methodology and a case study for the quantification of GHG emission reduction owing to advanced traffic control systems. [source] A Spatial Analysis of Residential Greenhouse Gas Emissions in the Toronto Census Metropolitan AreaJOURNAL OF INDUSTRIAL ECOLOGY, Issue 2 2007Jared R. VandeWeghe Residential greenhouse gas (GHG) emissions in the Toronto Census Metropolitan Area are spatially analyzed to determine the impact of urban form on emission-causing activities. The key finding is that over the entire region, emissions from private auto use are on par with those from fuel use for building heating. Once beyond the transit-intensive central core, private auto emissions surpass the emissions from building operations. Variation in total auto- and building-related emissions is quite significant between census tracts, ranging from 3.1 to 13.1 tonnes of carbon dioxide equivalents per year. Of all tracts, the top ten in terms of GHG emission are located in the lower-density suburbs, and their high emissions were largely due to private auto use. [source] Effects of E-Commerce on Greenhouse Gas Emissions: A Case Study of Grocery Home Delivery in FinlandJOURNAL OF INDUSTRIAL ECOLOGY, Issue 2 2002Hanne Siikavirta Summary In this article, we present a literature review of the general and environmental effects of e-commerce in various parts of the demand-supply chain. These are further translated into effects on greenhouse gas (GHG) emissions in the food production and consumption system. The literature study revealed many opportunities for e-commerce to reduce GHG emissions in the food production and consumption system. Some possibly negative effects were also identified. Electronic grocery shopping (e-grocery) home delivery service was chosen as the subject of a case study because of its direct and indirect potential for reducing the GHG emissions in the food production and consumption system. GHG emission reduction potential through the implementation of various e-grocery home delivery strategies was quantified. Depending on the home delivery model used, it is possible to reduce the GHG emissions generated by grocery shopping by 18% to 87% compared with the situation in which household members go to the store themselves. We estimate that the maximum theoretical potential of e-grocery home delivery service for reducing the GHG emissions of Finland is roughly 0.3% to 1.3%; however, the current and estimated future market potential is much smaller, because the estimated market share of e-grocery services is only 10% by 2005. Narrowing the gap between the theoretical and the actual potential requires a model that would simultaneously provide additional value to the consumer and be profitable to companies. To be able to achieve significant reductions in GHG emissions, system-level innovations and changes are required. Further research is needed before conclusions can be reached as to whether e-commerce and e-grocery are useful tools in that respect. [source] The Ozone Component of Global Change: Potential Effects on Agricultural and Horticultural Plant Yield, Product Quality and Interactions with Invasive SpeciesJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 4 2009Fitzgerald Booker The productivity, product quality and competitive ability of important agricultural and horticultural plants in many regions of the world may be adversely affected by current and anticipated concentrations of ground-level ozone (O3). Exposure to elevated O3 typically results in suppressed photosynthesis, accelerated senescence, decreased growth and lower yields. Various approaches used to evaluate O3 effects generally concur that current yield losses range from 5% to 15% among sensitive plants. There is, however, considerable genetic variability in plant responses to O3. To illustrate this, we show that ambient O3 concentrations in the eastern United States cause substantially different levels of damage to otherwise similar snap bean cultivars. Largely undesirable effects of O3 can also occur in seed and fruit chemistry as well as in forage nutritive value, with consequences for animal production. Ozone may alter herbicide efficacy and foster establishment of some invasive species. We conclude that current and projected levels of O3 in many regions worldwide are toxic to sensitive plants of agricultural and horticultural significance. Plant breeding that incorporates O3 sensitivity into selection strategies will be increasingly necessary to achieve sustainable production with changing atmospheric composition, while reductions in O3 precursor emissions will likely benefit world food production and reduce atmospheric concentrations of an important greenhouse gas. [source] Methodology for the design and evaluation of distillation systems: Exergy analysis, economic features and GHG emissionsAICHE JOURNAL, Issue 7 2010Hajnalka Kencse Abstract This work presents a process design methodology that evaluates the distillation systems based on exergetic, economic, and greenhouse gas (GHG) emission aspects. The aim of the methodology is to determine how these three features should be applied in process design to obtain information about the accuracy of the design alternatives. The methodology is tested and demonstrated on three different energy-integrated distillation systems: the direct sequence with backward heat-integration (DQB), fully thermally coupled distillation column (FTCDC), and sloppy distillation system with forward heat-integration (SQF). The average relative emission saving is the highest for the DQB scheme and this sequence shows the most flexible range of use. The case studies prove the accuracy of our evaluation methodology. On the other hand, it highlights and demonstrates that the exergy analysis can predict the results of the economic study and the environmental evaluation to make the decisions, associated with process design, much simpler. © 2009 American Institute of Chemical Engineers AIChE J, 2010 [source] THE FUTURE TRAJECTORY OF U.S. CO2 EMISSIONS: THE ROLE OF STATE VS.JOURNAL OF REGIONAL SCIENCE, Issue 1 2007AGGREGATE INFORMATION ABSTRACT This paper provides comparisons of a variety of time-series methods for short-run forecasts of the main greenhouse gas, carbon dioxide, for the United States, using a recently released state-level data set from 1960,2001. We test the out-of-sample performance of univariate and multivariate forecasting models by aggregating state-level forecasts versus forecasting the aggregate directly. We find evidence that forecasting the disaggregate series and accounting for spatial effects drastically improves forecasting performance under root mean squared forecast error loss. Based on the in-sample observations we attempt to explain the emergence of voluntary efforts by states to reduce greenhouse gas emissions. We find evidence that states with decreasing per capita emissions and a "greener" median voter are more likely to push toward voluntary cutbacks in emissions. [source] First assessment of methane and carbon dioxide emissions from shallow and deep zones of boreal reservoirs upon ice break-upLAKES & RESERVOIRS: RESEARCH AND MANAGEMENT, Issue 1 2006Éric Duchemin Abstract Most studies dealing with greenhouse gas (GHG) emissions from large boreal reservoirs were conducted during the ice-free period. In this paper, the potential methane (CH4) and carbon dioxide emissions are estimated for two hydroelectric reservoirs, as well as for a small experimental reservoir from boreal latitudes (northern Quebec, Canada) at the ice break-up event through diffusion (diffusive fluxes) and release of bubbles (bubbling fluxes). The results of this preliminary study suggest that the winter diffusive fluxes at the air,water interface of the sampled reservoirs represent < 7% of their cumulative carbon emissions during the ice-free period. Furthermore, the release upon ice-break of CH4 bubbles accumulated under the ice cover during the winter could represent 2% of the summer carbon emissions from hydroelectric reservoirs in northern Quebec. The results presented herein suggest that the GHG emissions upon ice break-up from the boreal reservoirs investigated are a small, but non-negligible, component of their annual GHG emissions. [source] Advancement of renewables in Bangladesh and Thailand: Policy intervention and institutional settingsNATURAL RESOURCES FORUM, Issue 3 2006Sk Noim Uddin Abstract This article reviews and analyses the advancement of renewable sources of energy in Bangladesh and Thailand in terms of policy intervention and institutional settings. Since renewable forms of energy emit far smaller amounts of greenhouse gas compared with fossil fuels, their use should mitigate climate change impacts while contributing to the provision of energy services. The article turns first to a review of energy,environment trends and the potential for renewables in these two nations. It then discusses strategies for the advancement of renewables. It is argued that further significant efforts can be made towards the advancement of renewables in Bangladesh and Thailand. These two nations could also learn from the experience in industrialized nations and other developing nations with regard to requisite policy instruments and processes. A number of barriers remain to the advancement of renewables, especially in terms of policy arrangements, institutional settings, financing mechanisms and technologies. Resources, cooperation and learning are required in order to overcome such barriers and to foster the development of necessary policy measures. Implementation of the clean development mechanism (CDM) under the Kyoto Protocol, and replication and adaptation of effective strategies from other settings are possible avenues for this. [source] NOx Emissions Reduction Through Water InjectionNAVAL ENGINEERS JOURNAL, Issue 3 2006Ernst Radloff Transport Canada is committed to protect the environment and to achieve a more sustainable transportation system. The Transportation Development Centre of Transport Canada, in collaboration with the Environment Research and Measurement Division of Environment Canada, is conducting research on marine emissions control technologies to lower greenhouse gas (GHG) emissions. » The ongoing work on emissions control technologies comprises both laboratory and field trials. An initial round of laboratory tests demonstrated the viability of a Water Injection System (WIS) to reduce NOx emissions. The results indicate that the WIS has achieved a 20 to 28% NOx reduction over a 25 to 75% load range with a maximum of 33% water injection. The WIS was optimized during laboratory bench tests and will be installed on a RORO vessel operating between Montreal, Quebec, and St. John's, Newfoundland. The WIS provides a cost-effective solution for NOx reduction on Canadian vessels fitted with older medium-speed engines. [source] Quantifying the effects of fungicides and disease resistance on greenhouse gas emissions associated with wheat productionPLANT PATHOLOGY, Issue 6 2008P. M. Berry A method is presented to quantify the net effect of disease management on greenhouse gas (GHG) emissions per hectare of crop and per tonne of crop produce (grain, animal feed, flour or bioethanol). Calculations were based on experimental and survey data representative of UK wheat production during the period 2004,06. Elite wheat cultivars, with contrasting yields and levels of disease resistance, were compared. Across cultivars, fungicides increased yields by an average of 1·78 t ha,1 and GHG emissions were reduced from 386 to 327 kg CO2 eq. t,1 grain. The amount by which fungicides increased yield , and hence reduced emissions per tonne , was negatively correlated with cultivar resistance to septoria leaf blotch (Mycosphaerella graminicola, anamorph Septoria tritici). GHG emissions of treated cultivars were always less than those of untreated cultivars. Without fungicide use, an additional 0·93 Mt CO2 eq. would be emitted to maintain annual UK grain production at 15 Mt, if the additional land required for wheat production displaced other UK arable crops/set aside. The GHG cost would be much greater if grassland or natural vegetation were displaced. These additional emissions would be reduced substantially if cultivars had more effective septoria leaf blotch resistance. The GHGs associated with UK fungicide use were calculated to be 0·06 Mt CO2 eq. per annum. It was estimated that if it were possible to eliminate diseases completely by increasing disease resistance without any yield penalty and/or developing better fungicides, emissions could theoretically be reduced further to 313 kg CO2 eq. t,1 grain. [source] Stable isotope natural abundance of nitrous oxide emitted from Antarctic tundra soils: effects of sea animal excrement depositionsRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 22 2008Renbin Zhu Nitrous oxide (N2O), a greenhouse gas, is mainly emitted from soils during the nitrification and denitrification processes. N2O stable isotope investigations can help to characterize the N2O sources and N2O production mechanisms. N2O isotope measurements have been conducted for different types of global terrestrial ecosystems. However, no isotopic data of N2O emitted from Antarctic tundra ecosystems have been reported although the coastal ice-free tundra around Antarctic continent is the largest sea animal colony on the global scale. Here, we report for the first time stable isotope composition of N2O emitted from Antarctic sea animal colonies (including penguin, seal and skua colonies) and normal tundra soils using insitu field observations and laboratory incubations, and we have analyzed the effects of sea animal excrement depositions on stable isotope natural abundance of N2O. For all the field sites, the soil-emitted N2O was 15N- and 18O-depleted compared with N2O in local ambient air. The mean , values of the soil-emitted N2O were ,15N,=,,13.5,±,3.2, and ,18O,=,26.2,±,1.4, for the penguin colony, ,15N,=,,11.5,±,5.1, and ,18O,=,26.4,±,3.5, for the skua colony and ,15N,=,,18.9,±,0.7, and ,18O,=,28.8,±,1.3, for the seal colony. In the soil incubations, the isotopic composition of N2O was measured under N2 and under ambient air conditions. The soils incubated under the ambient air emitted very little N2O (2.93,µg,N2ON,kg,1). Under N2 conditions, much more N2O was formed (9.74,µg,N2ON,kg,1), and the mean ,15N and ,18O values of N2O were ,19.1,±,8.0, and 21.3,±,4.3,, respectively, from penguin colony soils, and ,17.0,±,4.2, and 20.6,±,3.5,, respectively, from seal colony soils. The data from in situ field observations and laboratory experiments point to denitrification as the predominant N2O source from Antarctic sea animal colonies. Copyright © 2008 John Wiley & Sons, Ltd. [source] Off-gas treatment carbon footprint calculator: Form and functionREMEDIATION, Issue 1 2008Lowell Kessel The quantification of greenhouse gas (GHG) emissions can be a powerful sustainability measurement indicator for assessing environmental impacts of various operations, which can include remediation of chemically impacted media or construction projects. A carbon footprint calculator was developed and is presented in this article as one tool for applying sustainable practices to environmental remediation,specifically to assess the GHG footprint for remediation projects. The calculator is constructed from a compilation of published metrics and "standards." © 2008 Wiley Periodicals, Inc. [source] Isotope applications in environmental investigations part II: Groundwater age dating and recharge processes, and provenance of sulfur and methaneREMEDIATION, Issue 2 2003Julie K. Sueker Measurement of the isotopic composition of solids, solutes, gases, and water complement standard hydrogeological investigation techniques by providing information that may not otherwise be obtainable. Groundwater age estimates determined from the decay of radio-isotopes or from groundwater concentrations of anthropogenic gases such as chlorofluorocarbons (CFCs) and sulfur hexafluoride (SF6) are used to verify flow regimes and constrain or calibrate hydrologic flow models. Groundwater recharge rates are estimated by measuring the concentrations or activities of a variety of isotopes including 2H, 3H, 18O, and 36Cl. Excess sulfur causes salinization of water supplies and acidification of precipitation, surface water, and groundwater. The wide range of sulfur isotopic compositions exhibited by different sulfur species and sources allows the application of sulfur isotopes to trace sources and fate of sulfur in the environment. Methane is a ubiquitous gas that has economic value when located in extractable reservoirs. Methane is also a greenhouse gas and is a potential explosion and health hazard when it accumulates in buildings and water distribution systems. The carbon and hydrogen isotopic composition of methane can be used to determine the provenance of methane, distinguishing between thermogenic and biogenic sources. The addition of isotopic analyses to environmental investigations can be a cost-effective means of resolving intractable issues. © 2003 Wiley Periodicals, Inc. [source] Factors affecting methane production and mitigation in ruminantsANIMAL SCIENCE JOURNAL, Issue 1 2010Masaki SHIBATA ABSTRACT Methane (CH4) is the second most important greenhouse gas (GHG) and that emitted from enteric fermentation in livestock is the single largest source of emissions in Japan. Many factors influence ruminant CH4 production, including level of intake, type and quality of feeds and environmental temperature. The objectives of this review are to identify the factors affecting CH4 production in ruminants, to examine technologies for the mitigation of CH4 emissions from ruminants, and to identify areas requiring further research. The following equation for CH4 prediction was formulated using only dry matter intake (DMI) and has been adopted in Japan to estimate emissions from ruminant livestock for the National GHG Inventory Report: Y = ,17.766 + 42.793X , 0.849X2, where Y is CH4 production (L/day) and X is DMI (kg/day). Technologies for the mitigation of CH4 emissions from ruminants include increasing productivity by improving nutritional management, the manipulation of ruminal fermentation by changing feed composition, the addition of CH4 inhibitors, and defaunation. Considering the importance of ruminant livestock, it is essential to establish economically feasible ways of reducing ruminant CH4 production while improving productivity; it is therefore critical to conduct a full system analysis to select the best combination of approaches or new technologies to be applied under long-term field conditions. [source] Carbon pollution (greenhouse gas) measurement and reportingASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 4 2010Andrew Gunst Abstract The processes of Carbon Reporting and Emissions Trading in countries including the United States and Australia have developed from appearing unlikely in 2007 to the implementation of mandatory data reporting commencing in July 2008 in Australia and January 2010 in the United States. The onus is on emitting corporations to determine whether they must report. The data reported will have financial importance if and when Australia and the United States join Europe in placing a price on Carbon. To date, much of the public discussion in these countries has centred on the financial aspects of a Carbon tax or Emissions Trading Scheme (ETS). However, significant challenges exist in identifying and quantifying the emissions which the financial community seeks to trade, and business community understanding of the details of greenhouse emissions is not strong. Greenhouse emission reporting regulations and guidelines in Australia, where the first mandatory reports have been lodged by the 680 largest emitters, are outlined. Industrial examples are used to illustrate the challenges of understanding greenhouse gas emissions and their estimation, and how Chemical Engineering methodologies are useful in overcoming these challenges. Copyright © 2010 Curtin University of Technology and John Wiley & Sons, Ltd. [source] | |||||||||||||||||||||||||