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421.
The European Union (EU) is an important destination for developing country exports. Has the EU’s commitment to the Kyoto Protocol induced developing countries to reduce their carbon dioxide (CO2) emissions? Our analyses of 136 developing countries from 1981 through 2007 suggests that: developing countries’ export dependence on the EU is associated with CO2 emission reductions post-Kyoto in relation to the pre-Kyoto time period; this also holds for SO2, which, while not covered under Kyoto, is linked with CO2 emission levels; this does not hold for PM10, a pollutant which is not covered under Kyoto and is not directly associated with CO2 emissions related to industrial activities; developing countries’ export dependence on non-EU developed countries and on the rest of the world is not associated with significant reductions in emissions between pre- and post-Kyoto for these pollutants . In sum, even in the absence of binding regulatory mandates, the EU appears to exert market leverage to project its regulatory preferences abroad. 相似文献
422.
YouTube videos are a ubiquitous source of information but also a venue for users to comment on discussion boards that addend videos. There are no moderators of these discussions, and thus there is a possibility for self-appointed leaders to emerge, responding incessantly and across a genre of videos. These “elites,” as they are labelled here, use the discussion as a personal campaign tool, diminishing the deliberative potential of provocative topics. To determine whether this is happening and to complement existing research analyzing the content of comments, this paper focuses on the structure of the discussions that follow the most popular climate change-related videos. Network analysis confirms that discussions can be elite-driven, appearing in two different network structure types. Among the core group of elite commenters, most are either climate change activists or sceptics, and the most prolific commenters among this core group are activists. 相似文献
423.
Life cycle assessments of municipal solid waste management systems: A comparative analysis of selected peer-reviewed literature 总被引:1,自引:0,他引:1
Life cycle assessment (LCA) is a popular tool used to evaluate the environmental performance of municipal solid waste (MSW) management systems. Although reviews of LCAs of MSW have been undertaken to assess the validity of the ‘waste hierarchy,’ a recent review of the goal, scope and results of LCAs of mixed-material MSW management systems has yet to be performed. This paper is a comparative analysis of 20 process-based LCAs of MSW published between 2002 and 2008 in a total of 11 English-language peer-reviewed journals. It quantifies the methodological transparency of the studies and the frequency of use of particular system boundaries, types of data sources, environmental impact categories, impact weightings, economic valuations, sensitivity analyses, and LCA computer models. Net energy use (NEU), global warming potential (GWP), and acidification potential (AP) values for various types of MSW management systems are also compared using statistical indicators.The reviewed LCAs differ substantially in their system boundaries. Half or more of the LCAs either do not mention or are unclear in whether or not life cycle emissions from energy inputs or capital equipment are included in the calculation of results. Only four impact categories are common to more than half of the reviewed LCAs. The human and ecological toxicity impact categories are much less common than global warming potential, acidification, and eutrophication.A financial life cycle costing is present in eight of the reviewed LCAs, while an economic valuation of the environmental impacts is observed in five. Explicit sensitivity analyses are present in 4/20 of the studies, although many more LCAs evaluate the effects of varying model parameters by increasing the number of waste management scenarios. There is no consensus on whether or not to use the marginal or average source of electricity in calculating environmental impacts. Eight out of the 20 do not mention this source while the remaining LCAs are evenly split between the marginal and average electricity source. One quarter of the reviewed LCAs supply weighted results for the overall environmental performance of MSW management scenarios. All but one of these concurred with the ‘hierarchy of waste’ that the environmental performance of landfilling is lower than that of all the other treatment methods, and that thermal treatments are inferior to recycling.The comparative analyses of the NEU, GWP and AP results are based on 37, 45, and 42 MSW management scenarios, respectively. As measures of statistical dispersion, the interquartile ranges of the NEU, GWP and AP values are lowest for the landfilling (AP, NEU) and thermal treatment (GWP) scenarios. The results of the statistical analysis of the NEU, AP and GWP values appear to indicate that thermal treatment scenarios have a better environmental performance than landfilling, while the results for mixed treatment scenarios are less obvious. A comparison of the relative environmental performances of MSW treatment scenario types within each study did not provide a clear confirmation or repudiation of the waste hierarchy.This paper concludes that many recently published LCAs do not ensure that the methodological assumptions are made clear to the reader. Lack of transparency makes the results difficult to interpret, and hampers meaningful comparisons between the LCA results. A convergence in the adoption of particular assumptions that are more representative of MSW management systems would facilitate the comparison of the results. 相似文献
424.
S. A. Shavnin I. A. Yusupov A. A. Montile D. Yu. Golikov A. I. Montile 《Russian Journal of Ecology》2009,40(1):1-5
The effect of increased ambient temperature on the vertical, radial, and volume increments of Scots pine (Pinus sylvestris L.) trees has been studied in the zone of thermal impact from a burning petroleum gas flare. Regular age-dependent changes in the pattern of increment dependence on the distance from the flare and ambient temperature have been revealed. The mechanisms of these changes are explained. It is concluded that an increase in ambient temperature by 1.0–1.5° C has a favorable effect on the dynamics of Scots pine growth. 相似文献
425.
Global warming has greatly concerned the whole world. Owing to the limitation we currently have, it is still difficult to completely understand the mechanism and physical science of climate change. Now both certainty and uncertainty coexist in the understanding of climate warming. This paper aims to summarize certainties and uncertainties in climate-warming studies, which focus on seven key problems related to human activities, namely, global warming, atmospheric concentrations of greenhouse gases, relationship between greenhouse gas emissions and climate warming, climate models, future climate change, 2°C warming threshold and tipping point in the Earth’s system. We should comprehensively take into account the level of certainty and uncertainty in our understanding of climate change while adapting to and mitigating global warming and adjusting our industrial structures accordingly. This would allow us to respond to change with certainty, while avoiding the risks associated with uncertainty. 相似文献
426.
全球气候变化研究初探 总被引:3,自引:0,他引:3
全球气候变化尤其气候变暖对人类生存环境的影响已受到国际社会的普遍关注.二战以后,随着人口的急剧增多和社会的现代化,环境污染与全球变暖的趋势不断加重.为了人类生存的需要,必须加强对气候变暖的了解和研究,并采取相应措施阻止或减缓全球气候变暖的过程. 相似文献
427.
依据哈尔滨市1970-2005年的探空资料,采用线性模拟、相关和回归等分析方法,对哈尔滨市35年来地面及高空气候的变化进行分析和预测。研究结果认为:①哈尔滨市对流层中下层、平流层下层气候变化明显,对流层中下层气候变暖变湿,且对流层下层经向风速变小,年平均风速也变小,其中值得关注的是温度升高可延伸到400hPa,比湿增加也从地面延伸到400hPa;②建立了二氧化碳与水汽之间的关系方程,二氧化碳增加,水汽含量也随之增加,二氧化碳每增加一个单位,水汽就增加0.011g/kg;③各层次温度与比湿存在线性关系,水汽对各层次温度所起到的增加作用,随高度的增加增温效果越明显。 相似文献
428.
In this study we utilize content analysis techniques to examine how the issue of global warming and climate change has been characterized during the period of 1992 through 2005 by the Houston Chronicle—the largest regional newspaper in the Texas coastal region. A total of 795 global warming and climate change news articles from the Houston Chronicle are collected, coded and analyzed. Data analyses are organized and presented with regard to issue salience, various issue attributes (issue image, scope, linkage, participant, proposed solution and responsible party), use of science, and scientific information sources cited in the news stories. We find that regional media attention to the global climate change issue generally increases over time and an overwhelming majority of the news articles view the issue as a harmful problem. However, given the scientific consensus that global warming will result in significant devastating climate change consequences to the coastal regions, there are still a fair number of news articles delivering mixed, undetermined or even non-harmful messages. We also find that climate change is often discussed as a national or international-global issue, and frequently linked to a number of other public issues rather than just being viewed as an environmental–ecological problem. Moreover, we find that emphasis on issue solutions is placed more on mitigation strategies than on adaptation behaviors, and that both governmental and non-governmental actions and responsibilities are suggested for dealing with climate change. In addition, our findings indicate that the regional newspaper in Texas obtains scientific information on climate change primarily from academic institutions. Implications of our findings and recommendations for future research are discussed in the concluding section. 相似文献
429.
S. Paramasivam K. Jayaraman Takela C. Wilson Ashok K. Alva Luma Kelson Leandra B. Jones 《Journal of environmental science and health. Part. B》2013,48(3):317-324
Ammonia (NH3) emission from livestock manures used in agriculture reduces N uptake by crops and negatively impacts air quality. This laboratory study was conducted to evaluate NH3emission from different livestock manures applied to two soils: Candler fins sand (CFS; light-textured soil, pH 6.8 and field capacity soil water content of 70 g kg? 1) from Lake Alfred, Florida and Ogeechee loamy sand (OLS; medium-textured soil, pH 5.2 and field capacity soil water content of 140 g kg? 1) from Savannah, Georgia. Poultry litter (PL) collected from a poultry farm near Douglas, Georgia, and fresh solid separate of swine manure (SM) collected from a farm near Clinton, North Carolina were used. Each of the soil was weighed in 100 g sub samples and amended with either PL or SM at rates equivalent to either 0, 2.24, 5.60, 11.20, or 22.40 Mg ha? 1 in 1L Mason jars and incubated in the laboratory at field capacity soil water content for 19 days to monitor NH3 volatilization. Results indicated a greater NH3 loss from soils amended with SM compared to that with PL. The cumulative NH3volatilization loss over 19 days ranged from 4 to 27% and 14 to 32% of total N applied as PL and SM, respectively. Volatilization of NH3 was greater from light-textured CFS than that from medium-textured OLS. Volatilization loss increased with increasing rates of manure application. Ammonia volatilization was lower at night time than that during the day time. Differences in major factors such as soil water content, temperature, soil type and live stock manure type influenced the diurnal variation in volatilization loss of NH3 from soils. A significant portion (> 50%) of cumulative NH3 emission over 19 d occurred during the first 5–7 d following the application of livestock manures. Results of this study demonstrate that application of low rates of livestock manure (≤ 5.60 Mg ha? 1) is recommended to minimize NH3 emissions. 相似文献
430.
In Life Cycle Assessment (LCA), carbon dioxide (CO2) emissions from biomass combustion are traditionally assumed climate neutral if the bioenergy system is CO2 flux neutral, i.e. the quantity of CO2 released approximately equals the amount of CO2 sequestered in biomass. This convention is a plausible assumption for fast growing biomass species, but is inappropriate for slower growing biomass, like forests. In this case, the climate impact from biomass combustion can be potentially underestimated if CO2 emissions are ignored, or overestimated, if biogenic CO2 is considered equal to anthropogenic CO2. The estimation of the effective climate impact should take into account how the CO2 fluxes are distributed over time: the emission of CO2 from bioenergy approximately occurs at a single point in time, while the absorption by the new trees is spread over several decades. Our research target is to include this dynamic time dimension in unit-based impact analysis, using a boreal forest stand as case study. The boreal forest growth is modelled with an appropriate function, and is investigated under different forestry regimes (affecting the growth rate and the year of harvest). Specific atmospheric decay functions for biomass-derived CO2 are then elaborated for selected combinations of forest management options. The contribution to global warming is finally quantified using the GWPbio index as climate metric. Results estimates the effects of these practices on the characterization factor used for the global warming potential of CO2 from bioenergy, and point out the key role played by the selected time horizon. 相似文献