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1.
Methane is, after carbon dioxide, the most important anthropogenic greenhouse gas. Governments plan to abate methane emissions. A crude set of estimates of reduction costs is included in FUND, an integratedassessment model of climate change. In a cost-benefit analysis, methane emission reduction is found to be instrumental in controlling the optimal rate of climate change. In a cost-effectiveness analysis, methane emission reduction largely replaces carbon dioxide emission reduction. Methane emission reduction reinforces the case for international cooperation in climate policy, but complicates the efficient allocation of emission reduction efforts. Methane emission reduction at the short run does not help to achieve the ultimate objective of the Framework Convention on Climate Change. 相似文献
2.
垃圾填埋场甲烷排放是全球人为温室气体排放的重要来源,对于整个大气中温室气体增加引起的气候效应的影响不容忽视,是世界各国现代化进程中迫切需要解决的一个严重的社会公害问题.文章从填埋场甲烷产生的相关因素、垃圾处理现状和填埋场甲烷减排技术等方面对国内外研究现状做了总结.甲烷的产生受填埋场中的垃圾特性、含水率、温度、pH值、填埋时间、渗滤液含量和其他因素影响.当前的填埋场减排技术包括原位减排、资源化利用和末端控制等,填埋场可以从多方面共同作用实现减排目标. 相似文献
3.
The shale gas boom in the United States spurred a shift in electricity generation from coal to natural gas. Natural gas combined cycle units emit half of the CO2 to produce the same energy as a coal unit; therefore, the market trend is credited for a reduction in GHG emissions from the US power sector. However, methane that escapes the natural gas supply chain may undercut these relative climate benefits. In 2016, Canada, the United States and Mexico pledged to reduce methane emissions from the oil and natural gas sector 40–45% from 2012 levels by 2025. This article reviews the science-policy landscape of methane measurement and mitigation relevant for meeting this pledge, including changes in US policy following the 2016 presidential election. Considerable policy incoherence exists in all three countries. Reliable inventories remain elusive; despite government and private sector research efforts, the magnitude of methane emissions remains in dispute. Meanwhile, mitigation efforts vary significantly. A framework that integrates science and policy would enable actors to more effectively inform, leverage and pursue advances in methane measurement and mitigation. The framework is applied to North America, but could apply to other geographic contexts.
Key policy insights
The oil and gas sector’s contribution to atmospheric methane concentrations is becoming an increasingly prominent issue in climate policy.
Efforts to measure and control fugitive methane emissions do not presently proceed within a coherent framework that integrates science and policy.
In 2016, the governments of Canada, Mexico and the United States pledged to reduce methane emissions from the oil and natural gas sector 40–45% from 2012 levels by 2025.
The 2016 presidential election in the United States has halted American progress at the federal level, suggesting a heavier reliance on industry and subnational efforts in that country.
Collectively or individually, the countries, individual agencies, or private stakeholders could use the proposed North American Methane Reduction framework to direct research, enhance monitoring and evaluate mitigation efforts, and improve the chances that continental methane reduction targets will be achieved.
4.
Methane emissions from livestock enteric fermentation and manure management represent about 40% of total anthropogenic greenhouse
gas emissions from the agriculture sector and are projected to increase substantially in the coming decades, with most of
the growth occurring in non-Annex 1 countries. To mitigate livestock methane, incentive policies based on producer-level emissions
are generally not feasible because of high administrative costs and producer transaction costs. In contrast, incentive policies
based on sectoral emissions are likely administratively feasible, even in developing countries. This study uses an economic
model of global agriculture to estimate the effects of two sectoral mitigation policies: a carbon tax and an emissions trading
scheme based on average national methane emissions per unit of commodity. The analysis shows how the composition and location
of livestock production and emissions change in response to the policies. Results illustrate the importance of global mitigation
efforts: when policies are limited to Annex 1 countries, increased methane emissions in non-Annex 1 countries offset approximately
two-thirds of Annex 1 emissions reductions. While non-Annex 1 countries face substantial disincentives to enacting domestic
carbon taxes, developing countries could benefit from participating in a global sectoral emissions trading scheme. We illustrate
one scheme in which non-Annex 1 countries collectively earn USD 2.4 billion annually from methane emission permit sales when
methane is priced at USD 30/t CO2-eq. 相似文献
5.
Peter J. Marcotullio Andrea Sarzynski Jochen Albrecht Niels Schulz 《Global Environmental Change》2012,22(4):944-958
This paper aims to advance two objectives: (1) identify and explore greenhouse gas emissions from urban areas in Asia at the regional level; and (2) explore covariates of urban greenhouse gas emissions. We use the Emissions Database for Global Atmospheric Research estimates for carbon dioxide, methane, nitrous oxide, and sulfur hexafluoride from 14 source activities for the year 2000, which are allocated on a 1/10° global grid. We extract emissions for 3535 urban extents all with populations over 50,000, accounting for approximately 91% of the region's urban population. We use regression analysis to associate emissions with urban area and growth, economic, and biophysical characteristics. Our findings suggest that urban areas account for between 30 and 38% of total anthropogenic greenhouse gas emissions for the region and that emission per capita averages from urban areas are lower than those at the national level. Important covariates for total urban greenhouse gas emissions include population size, density and growth rate, income per capita, development status and elevation. This is a first and preliminary assessment of regional baseline trends using these data and this top-down analysis. 相似文献
6.
Xiaoyan Zhang Xiyan Xu Gensuo Jia Benjamin Poulter Zhen Zhang 《Climate Dynamics》2020,54(9):4095-4107
The variability of methane emissions from wetlands in the tropics and northern temperate regions can explain more than 70% of the interannual variation in global wetland methane emissions, which are largely driven by climate variability. We use climate reanalysis, remote sensing wetland area dataset and simulations from 11 land models contributing to Global Methane Budget to investigate the interannual variation and anomalies of wetland methane emissions in the Asian Monsoon region. Methane emissions in this region steadily increased over 2000–2012. However, abnormally low methane emissions were found in equatorial fully humid (Af), warm temperate winter dry (Cw), and warm temperate fully humid (Cf) Asian Monsoon climate sub-regions in 2008, 2009 and 2011, respectively. These spatially-shifting low emissions occurred simultaneously with observed wetland area shrinkage due to abnormally low precipitation. Interannual variability of wetland methane emissions in Asian Monsoon region are primarily driven by South Asian Monsoon system. However, the abnormally low emissions are related to strong La Niña events, and its accompanying effect of weakened East Asian Monsoon system and eastward Western Pacific subtropical high, which drives the shifting pattern of rainfall, and thus the spatial pattern of methane emission anomalies. 相似文献
7.
Deforestation, the second largest source of anthropogenic greenhouse gas emissions, is largely driven by expanding forestry and agriculture. However, despite agricultural expansion being increasingly driven by foreign demand, the links between deforestation and foreign demand for agricultural commodities have only been partially mapped. Here we present a pan-tropical quantification of carbon emissions from deforestation associated with the expansion of agriculture and forest plantations, and trace embodied emissions through global supply chains to consumers. We find that in the period 2010–2014, expansion of agriculture and tree plantations into forests across the tropics was associated with net emissions of approximately 2.6 gigatonnes carbon dioxide per year. Cattle and oilseed products account for over half of these emissions. Europe and China are major importers, and for many developed countries, deforestation emissions embodied in imports rival or exceed emissions from domestic agriculture. Depending on the trade model used, 29–39% of deforestation-related emissions were driven by international trade. This is substantially higher than the share of fossil carbon emissions embodied in trade, indicating that efforts to reduce greenhouse gas emissions from land-use change need to consider the role of international demand in driving deforestation. Additionally, we find that deforestation emissions are similar to, or larger than, other emissions in the carbon footprint of key forest-risk commodities. Similarly, deforestation emissions constitute a substantial share (˜15%) of the total carbon footprint of food consumption in EU countries. This highlights the need for consumption-based accounts to include emissions from deforestation, and for the implementation of policy measures that cross these international supply-chains if deforestation emissions are to be effectively reduced. 相似文献
8.
《Global Environmental Change》1999,9(3):179-201
Anthropogenic sources of methane emissions are thought to be nearly twice as high as emissions from natural sources. As the second most important anthropogenic greenhouse gas after carbon dioxide, methane ought to be addressed by policy makers when they consider reductions of national greenhouse-gas inventories. This article first comprehensively reviews source and sink estimates of methane by natural and anthropogenic sectors (wetlands, wet-paddy rice farming, livestock farming, biomass burning, landfills, coal mining, and venting of natural gas or natural-gas pipeline leaks), then proceeds to suggest where different mitigation strategies might be applied. The final section considers how the scenario of a warmer planet may affect the methane biogeochemical cycle. 相似文献
9.
Unanticipated sabotage of two underwater pipelines in the Baltic Sea(Nord Stream 1 and 2) happened on 26September 2022. Massive quantities of natural gas, primarily methane, were released into the atmosphere, which lasted for about one week. As a more powerful greenhouse gas than CO2, the potential climatic impact of methane is a global concern.Using multiple methods and datasets, a recent study reported a relatively accurate magnitude of the leaked methane at 0.22 ±0.03 million tons(... 相似文献
10.
The use of shale gas is commonly considered as a low-cost option for meeting ambitious climate policy targets. This article explores global and country-specific effects of increasing global shale gas exploitation on the energy markets, on greenhouse gas emissions, and on mitigation costs. The global techno-economic partial equilibrium model POLES (Prospective Outlook on Long-term Energy Systems) is employed to compare policies which limit global warming to 2°C and baseline scenarios when the availability of shale gas is either high or low. According to the simulation results, a high availability of shale gas has rather small effects on the costs of meeting climate targets in the medium and long term. In the long term, a higher availability of shale gas increases baseline emissions of greenhouse gases for most countries and for the world, and leads to higher compliance costs for most, but not all, countries. Allowing for global trading of emission certificates does not alter these general results. In sum, these findings cast doubt on shale gas’s potential as a low-cost option for meeting ambitious global climate targets.
POLICY RELEVANCE
Many countries with a large shale gas resource base consider the expansion of local shale gas extraction as an option to reduce their GHG emissions. The findings in this article imply that a higher availability of shale gas in these countries might actually increase emissions and mitigation costs for these countries and also for the world. An increase in shale gas extraction may spur a switch from coal to gas electricity generation, thus lowering emissions. At the global level and for many countries, though, this effect is more than offset by a crowding out of renewable and nuclear energy carriers, and by lower energy prices, leading to higher emissions and higher mitigation costs in turn. These findings would warrant a re-evaluation of the climate strategy in most countries relying on the exploitation of shale gas to meet their climate targets. 相似文献
11.
Joanne H. Shorter J. Barry Mcmanus Charles E. Kolb Eugene J. Allwine Brian K. Lamb Byard W. Mosher Robert C. Harriss Uwe Partchatka Horst Fischer Geoffrey W. Harris Paul J. Crutzen Hans-Josef Karbach 《Journal of Atmospheric Chemistry》1996,24(2):121-140
We have investigated methane emissions from urban sources in the former East Germany using innovative measurement techniques including a mobile real-time methane instrument and tracer release experiments. Anthropogenic and biogenic sources were studied with the emphasis on methane emissions from gas system sources, including urban distribution facilities and a production plant. Methane fluxes from pressure regulating stations ranged from 0.006 to 24. l/min. Emissions from diffuse sources in urban areas were also measured with concentration maps and whole city flux experiments. The area fluxes of the two towns studied were 0.37 and 1.9 g/m2/s. The emissions from individual gas system stations and total town emissions of this study are comparable to results of similar sites examined in the United States. 相似文献
12.
By GUNNAR BÖRJESSON JERKER SAMUELSSON JEFFREY CHANTON ROLF ADOLFSSON BO GALLE BO H. SVENSSON 《Tellus. Series B, Chemical and physical meteorology》2009,61(2):424-435
Seven Swedish landfills were investigated from 2001 to 2003. On each landfill, a measure of the total methane production was calculated from data on: (1) methane emissions (leakage); (2) methane oxidation and (3) from gas recovery.
Methane emissions were determined via a tracer gas (N2 O) release-based remote sensing method. N2 O and CH4 were measured with an Fourier Transform infrared detector at a distance of more than 1 km downwind from the landfills. Methane oxidation in the landfill covers was measured with the stable carbon isotope method. The efficiency in gas recovery systems proved to be highly variable, but on an average, 51% of the produced landfill gas was captured.
A first-order decay model, based on four fractions (waste from households and parks, sludges and industrial waste), showed that the use of a degradable organic carbon fraction (DOCf) value of 0.54, in accordance with the default value for DOCf of 0.50 in the latest IPCC model, gave an emission estimate similar to the official national reports. 相似文献
Methane emissions were determined via a tracer gas (N
A first-order decay model, based on four fractions (waste from households and parks, sludges and industrial waste), showed that the use of a degradable organic carbon fraction (DOCf) value of 0.54, in accordance with the default value for DOCf of 0.50 in the latest IPCC model, gave an emission estimate similar to the official national reports. 相似文献
13.
Reliable estimates of carbon and other environmental footprints of agricultural commodities require capturing a large diversity of conditions along global supply chains. Life Cycle Assessment (LCA) faces limitations when it comes to addressing spatial and temporal variability in production, transportation and manufacturing systems. We present a bottom-up approach for quantifying the greenhouse gas (GHG) emissions embedded in the production and trade of agricultural products with a high spatial resolution, by means of the integration of LCA principles with enhanced physical trade flow analysis. Our approach estimates the carbon footprint (as tonnes of carbon dioxide equivalents per tonne of product) of Brazilian soy exports over the period 2010–2015 based on ~90,000 individual traded flows of beans, oil and protein cake identified from the municipality of origin through international markets. Soy is the most traded agricultural commodity in the world and the main agricultural export crop in Brazil, where it is associated with significant environmental impacts. We detect an extremely large spatial variability in carbon emissions across sourcing areas, countries of import, and sub-stages throughout the supply chain. The largest carbon footprints are associated with municipalities across the MATOPIBA states and Pará, where soy is directly linked to natural vegetation loss. Importing soy from the aforementioned states entailed up to six times greater emissions per unit of product than the Brazilian average (0.69 t t−1). The European Union (EU) had the largest carbon footprint (0.77 t t−1) due to a larger share of emissions from embodied deforestation than for instance in China (0.67 t t−1), the largest soy importer. Total GHG emissions from Brazilian soy exports in 2010–2015 are estimated at 223.46 Mt, of which more than half were imported by China although the EU imported greater emissions from deforestation in absolute terms. Our approach contributes data for enhanced environmental stewardship across supply chains at the local, regional, national and international scales, while informing the debate on global responsibility for the impacts of agricultural production and trade. 相似文献
14.
附件一国家温室气体排放趋势及其履约进展 总被引：2，自引：0，他引：2
对《联合国气候变化框架公约》秘书处最新公布的温室气体排放数据进行统计分析,结果显示：相对于基准年（1990年）,附件一国家温室气体排放总量整体呈下降趋势。其中,经济转型期国家温室气体排放总量总体上呈逐年下降趋势,非经济转型期国家的温室气体排放总量有逐年增长的趋势。美国和加拿大能源部门的温室气体排放量增长最为显著,相对于1990年,2005年其增幅分别为19.2%和28.6%;英国和德国能源部门温室气体减排量最为显著,其减幅分别为7.8%和17.4%。在2005年,有超过一半的附件一国家的实际排放量低于其目标排放量,履约进展状况良好。 相似文献
15.
采用静态箱-气相色谱法在江汉平原开展早稻、晚稻、中稻、虾稻和再生稻5种稻作类型温室气体排放监测试验,研究不同稻作模式下稻田CH4和N2O排放特征、总增温潜势及温室气体排放强度,为准确评估稻田生态系统温室气体排放提供参考依据。结果表明:CH4排放集中在水稻前期淹水阶段,排放峰值最高为虾稻(85.7 mg·m-2·h-1),较其他稻作模式高71.7%～191.5%。N2O排放峰值主要出现于中期晒田和施肥阶段,排放峰值最高为再生稻(1100.7μg·m-2·h-1),较其他稻作模式高16.8%～654.9%。CH4累积排放量从大到小依次为虾稻、再生稻、早稻、晚稻、中稻;N2O累积排放量从大到小依次为再生稻、早稻、晚稻、中稻、虾稻;总增温潜势从大到小依次为虾稻、再生稻、早稻、晚稻、中稻;温室气体排放强度从大到小依次为虾稻、早稻、再生稻、晚稻、中稻。CH4排... 相似文献
16.
对《联合国气候变化框架公约》秘书处最新公布的温室气体排放数据进行统计分析,结果显示：相对于基准年（1990年）,附件一国家温室气体排放总量整体呈下降趋势。其中,经济转型期国家温室气体排放总量总体上呈逐年下降趋势,非经济转型期国家的温室气体排放总量有逐年增长的趋势。美国和加拿大能源部门的温室气体排放量增长最为显著,相对于1990年,2005年其增幅分别为19.2%和28.6%;英国和德国能源部门温室气体减排量最为显著,其减幅分别为7.8%和17.4%。在2005年,有超过一半的附件一国家的实际排放量低于其目标排放量,履约进展状况良好。 相似文献
17.
Modeling Methane Emissions from Paddy Rice Fields under Elevated Atmospheric Carbon Dioxide Conditions 总被引：1，自引：0，他引：1
Methane(CH4 ) emissions from paddy rice fields substantially contribute to the dramatic increase of this greenhouse gas in the atmosphere.Due to great concern about climate change,it is necessary to predict the effects of the dramatic increase in atmospheric carbon dioxide(CO2 ) on CH4 emissions from paddy rice fields.CH4MOD 1.0 is the most widely validated model for simulating CH4 emissions from paddy rice fields exposed to ambient CO2(hereinafter referred to as aCO2 ).We upgraded the model to CH4MOD 2.0 b... 相似文献
18.
Tom M. L. Wigley 《Climatic change》2011,108(3):601-608
Carbon dioxide (CO2) emissions from fossil fuel combustion may be reduced by using natural gas rather than coal to produce energy. Gas produces
approximately half the amount of CO2 per unit of primary energy compared with coal. Here we consider a scenario where a fraction of coal usage is replaced by
natural gas (i.e., methane, CH4) over a given time period, and where a percentage of the gas production is assumed to leak into the atmosphere. The additional
CH4 from leakage adds to the radiative forcing of the climate system, offsetting the reduction in CO2 forcing that accompanies the transition from coal to gas. We also consider the effects of: methane leakage from coal mining;
changes in radiative forcing due to changes in the emissions of sulfur dioxide and carbonaceous aerosols; and differences
in the efficiency of electricity production between coal- and gas-fired power generation. On balance, these factors more than
offset the reduction in warming due to reduced CO2 emissions. When gas replaces coal there is additional warming out to 2,050 with an assumed leakage rate of 0%, and out to
2,140 if the leakage rate is as high as 10%. The overall effects on global-mean temperature over the 21st century, however,
are small. 相似文献
19.
D. G. Victor 《Climatic change》1992,20(2):113-141
A model of the U.S. automobile market is used to test the role that natural gas vehicles (NGVs) might play in reducing greenhouse-gas emissions. Since natural gas (primarily methane) emits less CO2 per unit of energy than petroleum products, NGVs are an obvious pathway to lower CO2 emissions. High-and low-demand scenarios are used to forecast the emissions from unrestricted growth and a modest program of conservation, respectively. Based on these scenarios, a reference scenario is developed that projects a possible future path of automobile use and efficiency. It is found that without a dramatic increase in automobile use, fuel consumption and greenhouse-gas emissions from automobiles in the United States will probably decrease in the future, provided that efficiency continues to improve at modest rates. In theory, NGVs can help shift emissions even further down.A second objective is to quantify the role that leaking methane might play in offsetting some of the greenhouse advantages of NGVs. To do this, a simple atmospheric chemistry model is applied to the reference scenario; several leak rates and feedback factors are used to test the sensitivity of the projected green-house forcing from now until 2050. Committed warming beyond 2050 is not included, and the results should be interpreted with that in mind.It is highly unlikely that switching automobiles from gasoline to natural gas will appreciably lower future greenhouse forcing. Constraints on vehicle miles travelled as well as continued improvements in vehicle efficiency will make a much larger contribution towards controlling global warming. 相似文献
20.
Luiz Pinguelli Rosa Marco Aurelio dos Santos Bohdan Matvienko Ednaldo Oliveira dos Santos Elizabeth Sikar 《Climatic change》2004,66(1-2):9-21
This paper discusses emissions by power-dams in the tropics. Greenhouse gas emissions from tropical power-dams are produced underwater through biomass decomposition by bacteria. The gases produced in these dams are mainly nitrogen, carbon dioxide and methane. A methodology was established for measuring greenhouse gases emitted by various power-dams in Brazil. Experimental measurements of gas emissions by dams were made to determine accurately their emissions of methane (CH4) and carbon dioxide (CO2) gases through bubbles formed on the lake bottom by decomposing organic matter, as well as rising up the lake gradient by molecular diffusion.The main source of gas in power-dams reservoirs is the bacterial decomposition (aerobic and anaerobic) of autochthonous and allochthonous organic matter that basically produces CO2 and CH4. The types and modes of gas production and release in the tropics are reviewed. 相似文献