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991.
The expansion of the industrial economy and the increase of population in Northeast Asian countries have caused much interestin climate monitoring related to global warming. However, new techniques and better platforms for the measurement of globalwarming and regional databases are still old-fashioned and arenot being developed sufficiently. With respect to this agenda,since 1993, at the request of the World Meteorological Organization (WMO), to monitor functions of global warming, theKorea Meteorological Administration (KMA) has set up a Global Atmospheric Watch (GAW) Station on the western coast of Korea(Anmyun-do) and has been actively monitoring global warming overNortheast Asia. In addition, atmospheric carbon dioxide (CO2) has been measured for a similar KMA global warmingprogram at Kosan, Cheju Island since 1990. Aerosol and radiationhave also been measured at both sites as well as in Seoul. Theobservations have been analyzed using diagnostics of climate change in Northeast Asia and also have been internationally compared. Results indicate that greenhouse gases are in good statistic agreement with the NOAA/Climate Monitoring and Diagnostics Laboratory (CMDL) long-term trends of monthly meanconcentrations and seasonal cycles. Atmospheric particulatematter has also been analyzed for particular Asian types interms of optical depth, number concentration and size distribution. 相似文献
992.
To estimate the magnitude of climate change anticipated forCanada's 38 National Parks (NPs) and Park Reserves, seasonaltemperature and precipitation scenarios were constructed for 2050and 2090 using the Canadian Centre for Climate Modelling andAnalysis (CCCma) coupled model (CGCM1). For each park, we assessed impacts on physical systems, species, ecosystems andpeople. Important, widespread changes relate to marine andfreshwater hydrology, glacial balance, waning permafrost, increased natural disturbance, shorter ice season, northern andupward altitudinal species and biome shifts, and changed visitation patterns. Other changes are regional (e.g., combinedEast coast subsidence and sea level rise increase coastal erosionand deposition, whereas, on the Pacific coast, tectonic upliftnegates sea level rise). Further predictions concern individualparks (e.g., Unique fens of Bruce Peninsular NP will migratelakewards with lowered water levels, but structural regulation of Lake Huron for navigation and power generation would destroythe fens). Knowledge gaps are the most important findings. Forexample: we could not form conclusions about glacial massbalance, or its effects on rivers and fjords. Likewise, for theEast Coast Labrador Current we could neither estimate temperature and salinity effects of extra iceberg formation, nor the further effects on marine food chains, and breeding park seabirds. We recommend 1) Research on specific large knowledge gaps; 2) Climate change information exchange with protected area agencies in other northern countries; and 3) incorporating climate uncertainty into park plans and management. We discuss options for a new park management philosophy in the face of massive change and uncertainty. 相似文献
993.
Kalikhman I 《Environmental monitoring and assessment》2005,110(1-3):203-215
A mathematical model was used to compare the effects of a regular (one-pass) or interleaved (two-pass) acoustic survey on
the adequacy of reconstructing patchy distribution fields. The model simulates fish or plankton patches of different shapes
and spatial orientations, and a set of parallel or zigzag transects forming a regular or interleaved acoustic survey. The
efficiency of a survey is determined by the adequacy of a reconstructed field to that originally generated, which is evaluated
by calculating their correlations. Regarding the immovable fields, the efficiency of a regular or interleaved acoustic survey
was tested with the following two alternative assumptions: (1) the entire survey was completed; (2) the survey was interrupted
for some reason at the moment when one transect remained non-accomplished. In the former case, the efficiencies of both acoustic
surveys were nearly the same; in the latter case, the efficiency of an interleaved survey was superior to that of a regular
one. With respect to movable fields, the efficiency of the completed interleaved surveys was even higher than that of the
regular ones. Thus, the results obtained allow us to conclude that an interleaved survey is expedient in cases where there
is no preference regarding the position of a vessel for further work. 相似文献
994.
An assessment of potential biomass resources in Nigeria for the production of methane and power generation is presented in this paper. Nigeria, as an underdeveloped and populous country, needs an uninterrupted source of energy. The country's energy problems have crippled large sectors of the economy. The percentage of people connected to the national grid is 40%. These 40% experience electricity supply failure on average 10–12 hours daily. Energy generation from municipal solid waste (MSW) is an effective MSW management strategy. Yearly waste generation has increased from 6,471 gigagrams (Gg) in 1959 to 26,600 Gg in 2015. This amount is projected to reach 36,250 Gg per year by 2030. Methane emission for 2015 was 491 Gg, and it is projected to reach 669 Gg in 2030. These values translate to 3.48 × 109 kilowatt hours (kWh) of electricity for 2015, with a projected 4.74 × 109 kWh by 2030. The revenue to be derived from the electricity that is generated could have been US$365.04 × 106 for 2015, and it is estimated that it will reach US$473.82 × 106 by 2030. It was found that methane emissions from MSW increased with time, and capturing this gas for energy production will lead to a sustainable waste management. 相似文献
995.
Venkataramana Sridhar Parthkumar Modi Mirza M. Billah Prasanth Valayamkunnath Jonathan L. Goodall 《Journal of the American Water Resources Association》2019,55(4):780-799
Despite the advances in climate change modeling, extreme events pose a challenge to develop approaches that are relevant for urban stormwater infrastructure designs and best management practices. The study first investigates the statistical methods applied to the land‐based daily precipitation series acquired from the Global Historical Climatology Network‐Daily (GHCN‐D). Additional analysis was carried out on the simulated Multivariate Adaptive Constructed Analogs (MACA)‐based downscaled daily extreme precipitation of 15 General Circulation Models and Weather Research and Forecasting‐based hourly extreme precipitation of North American Regional Reanalysis to discern the return period of 24‐hr and 48‐hr events. We infer that the GHCN‐D and MACA‐based precipitation reveals increasing trends in annual and seasonal extreme daily precipitation. Both BCC‐CSM1‐1‐m and GFDL‐ESM2M models revealed that the magnitude and frequency of extreme precipitation events are projected to increase between 2016 and 2099. We conclude that the future scenarios show an increase in magnitudes of extreme precipitation up to three times across southeastern Virginia resulting in increased discharge rates at selected gauge locations. The depth‐duration‐frequency curve predicted an increase of 2–3 times in 24‐ and 48‐h precipitation intensity, higher peaks, and indicated an increase of up to 50% in flood magnitude in future scenarios. 相似文献
996.
中国环境管理面临实践困境和学科认同危机的双重考验。本文在回溯其环境学和公共管理的学科渊源基础上,分析了当下中国环境管理学的基本概念、学科归属、功能与定位,认为新时期应基于生态文明思想,重构中国环境管理学的规范价值、知识体系、政策工具与制度机制,提出了重构中国环境管理学的5项建议,包括须注意环境管理的回应性与前瞻性,学科专业性与跨学科协作并重,创新环境管理学的知识生产方式,搭建环境管理学同政治与大众对话的平台和机制,以及形成环境管理的理论、制度与实践相互转化的研究能力等。最后,提出以生态文明思想为引领,树立中国环境治理的道路自信、理论自信、制度自信、文化自信。 相似文献
997.
Jeroen van der Heijden 《Journal of Environmental Planning and Management》2019,62(3):446-465
It has been proposed that voluntary urban climate programmes overcome shortfalls in mandatory, top-down, state-led government interventions to address climate change risks. Such programmes seek commitments from households and firms to improve their environmental sustainability, but do not have the force of law. City governments are actively developing and implementing such programmes, seeking improved and accelerated urban climate action. There is little evidence, however, of whether their involvement positively affects voluntary programme performance. This article presents qualitative comparative analysis (QCA) of 26 voluntary programmes from Australia, the Netherlands and the US, seeking to understand whether, and if so how, city governments affect the performance of voluntary urban climate programmes. The results will help to inform city governments about the roles they may play in urban climate governance. 相似文献
998.
为研究受损钢结构改造施工安全预警状况,建立受损情况下钢结构改造施工安全预警指标体系,并针对BP神经网络算法易陷入局部最优的问题,提出了用改进粒子群算法(IPSO)对BP神经网络权重及阈值进行调整的IPSO-BP安全预警评估模型。通过分析某单层重钢厂房受损现状,针对其结构损伤情况和已构建的安全控制指标体系进行数值模拟分析。研究结果表明:与传统的BP模型相比,IPSO-BP模型具有更好的预测能力,构建的安全预警指标体系及预警模型可以很好地对受损钢结构改造施工过程安全状况进行综合评估,对受损钢结构改造施工安全控制具有一定的参考价值。 相似文献
999.
IntroductionWe present two studies that focus on the relationship between safety rules and the safety climate. It is expected that a reasoned acceptance, namely one based on an understanding of the bases for the rules and a collective management of the rules, should benefit the climate. Method: In an initial study (N = 202) employees replied to a questionnaire that measured the safety climate, the level of the relationship with the safety rules, and the understanding of their bases. The results highlighted the fact that a reasoned acceptance of the rules is associated with an understanding of their bases and predicts the level of safety. In a second study (N = 258) employees replied to a questionnaire measuring team reflexivity, the safety climate, and the level of relationship with the safety rules. We observed that collective management of the rules mediated the relation between team reflexivity and the safety climate. Results: The results are discussed from the point of view of their practical implications. Developing safety climate requires that operators are trained to understand the basis of safety rules and team reflexivity. 相似文献
1000.
Climate is a group‐level phenomenon that should be measured and studied at the group level. The group level has theoretical and methodological advantages over the individual level. In this paper, I theoretically review the assumptions in measuring climate at the individual and group levels and demonstrate that the group‐level assumptions are more adequate for climate research because of their influences in exposure to events, interpretation of events, and preservation of perceptions. Methodologically, I discuss advantages in group‐level climate measurement accuracy that are based on multiple evaluators of climate and I suggest group aggregation is an organizational form of “wisdom of the crowds.” Finally, I point to three topics that remain to be investigated to understand climate at the group level better. The first is use of variability measures to compensate for information that is lost in aggregation. The second is challenging the assumption that formal organizational structure defines the group boundaries. I suggest that other levels of analysis apply to group‐level climate measurement and demonstrate the use of informal, more natural groups as an additional level. Third, I point to recently developed statistical procedures that can aid the study of climate perception emergence over time. 相似文献