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991.
The adoption of the Warsaw mechanism on loss and damage has again highlighted the North-South divide in those parts of UNFCCC negotiations dealing with international climate finance. Current estimates put required funding from rich countries at 50–100 billion Euros per year to induce non-Annex I countries to take on greenhouse gas limitation commitments and to assist highly vulnerable countries. Results from survey-embedded conjoint experiments can help policy-makers anticipate opportunities and pitfalls in designing large-scale climate funding schemes. We implemented such experiments in the United States and Germany to better understand what institutional design characteristics are likely to garner more public support for climate funding among citizens in key developed countries. We find that climate funding receives more public support if it flows to efficient governments, funding decisions are made jointly by donor and recipient countries, funding is used both for mitigation and adaptation, and other donor countries contribute a large share. Contrary to what one might expect, climate change damage levels, income, and emissions in/of potential recipient countries have no significant effect on public support. These findings suggest that finance mechanisms that focus purely on compensating developing countries, without contributing to the global public good of mitigation, will find it hard to garner public support. 相似文献
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通过对陕西省教育厅举办过的两届中职学校工程测量大赛的结果总结,分析了目前中职学校工程测量教学中存在的问题及形成原因,对产生原因的各个方面进行了探讨,并提出了解决办法。 相似文献
996.
孟加拉湾风暴Mala登陆期间地形敏感试验 总被引:1,自引:0,他引:1
孟加拉湾是全球8个热带气旋易发生的地区之一。孟加拉湾风暴向偏北和偏东方向移动,会对中国青藏高原和西南地区形成重大影响,而孟加拉湾风暴的移动方向受到青藏高原和云贵高原大地形的影响很大。为了分析大地形对孟加拉湾风暴路径、结构变化和降水分布的作用和影响,文中利用WRF模式对2006年4月29—30日孟加拉湾风暴Mala的登陆过程进行数值模拟研究。试验结果表明:模拟风暴中心的路径和强度与实况虽有一定误差,但移动趋势均为东北方向,强度误差较小,表明WRF模式对本个例的模拟可以参考。通过不同地形高度敏感试验,分析风暴在登陆前后分别在全地形、半地形和零地形高度情况下的移动路径和速度、环流结构、动力结构以及在云南省产生的降水分布和强度。结果表明:风暴登陆前,大地形对风暴结构有间接影响,使高层出现倾斜。在风暴登陆过程中,地形的阻挡和摩擦作用能较明显影响风暴的移动路径和速度。风暴登陆后,地形抬升使风暴强度减弱,移动速度加快;结构由基本对称变为非对称,且斜压结构明显。地形对降水存在双重作用,一方面地形抬升使风暴产生的降水增加,另一方面地形摩擦使风暴强度减弱从而减少降水。 相似文献
997.
Simulated Spatiotemporal Response of Ocean Heat Transport to Freshwater Enhancement in North Atlantic and Associated Mechanisms 下载免费PDF全文
The Atlantic Meridional Overturning Circulation(AMOC)transports a large amount of heat to northern high latitudes,playing an important role in the global climate change.Investigation of the freshwater perturbation in North Atlantic(NA)has become one of the hot topics in the recent years.In this study,the mechanism and pathway of meridional ocean heat transport(OHT)under the enhanced freshwater input to the northern high latitudes in the Atlantic are investigated by an ocean-sea ice-atmosphere coupled model.The results show that the anomalous OHT in the freshwater experiment(FW)is dominated by the meridional circulation kinetic and ocean thermal processes.In the FW,OHT drops down during the period of weakened AMOC while the upper tropical ocean turns warmer due to the retained NA warm currents.Conversely,OHT recovers as the AMOC recovers,and the mechanism can be generalized as:1)increased ocean heat content in the tropical Southern Ocean during the early integration provides the thermal condition for the recovery of OHT in NA;2)the OHT from the Southern Ocean enters the NA through the equator alongthe deep Ekman layer;3)in NA,the recovery of OHT appears mainly along the isopycnic layers of 24.70-25.77 below the mixing layer.It is then transported into the mixing layer from the "outcropping points"innorthern high latitudes,and finally released to the atmosphere by the ocean-atmosphere heat exchange. 相似文献
998.
In this paper, the seismic response reduction performance of magnetorheological (MR) damper is experimentally investigated for a suspension bridge. First, the force–displacement and force–velocity curves under a range of excitation frequencies, amplitudes and currents are obtained by mechanical behavior test of the RD1097 type MR damper. Then a new non-linear hysteretic model is proposed to model the mechanical behavior of the MR damper and the model parameters are identified from test data. An experimental method, as well as a set of testing setups with the MR damper for longitudinal seismic response reduction of a SDOF generalized system representing the fundamental longitudinal mode of suspension bridge, is developed. Finally, the seismic response reduction experiment subject to three kinds of earthquake excitations, including the Pingsheng Bridge earthquake wave, the El-Centro wave and the Taft wave, is carried out, and nine control cases, including uncontrolled, six passive control schemes with different input currents and two semi-active Bang–Bang control schemes, are tested. The results verify that the seismic response reduction experimental method is feasible and the good performance of seismic longitudinal response reduction of the suspension bridge can be achieved by MR damper. It is also shown that the passive control with optimum input current outperforms the semi-active Bang–Bang controls. 相似文献
999.
目的:探讨CT平扫、CT血流灌注成像(CTP)、磁共振弥散加权成像(DWI)及螺旋CT血管造影(CTA)对缺血性脑血管病的比较影像学价值,找出缺血性脑血管病的合理影像检查路径。方法:30例缺血性脑血管病患者经CT、CTA、CTP、DWI检查。结果:30例患者中,12例CT平扫显示责任病灶,27例CTA显示责任血管。DWI与CTP对缺血性脑血管病的敏感性分别为73.3%,83.3%,阳性预测值分别为95.7%,92.6%,两者无显著性差异。结论:CT平扫是常规筛选检查,CTP和DWI是发现脑组织缺血改变的敏感方法,CTA适用于确定责任血管。CTP和DWI、CTA检查可根据病人经济条件及临床表现灵活选择。 相似文献
1000.
Conflicting sorption coefficients for ortho‐phenylphenol (OPP) have been reported in the literatures, which resulted in the conflicting assessments on OPP mobility in soil. To ascertain the sorption coefficient of OPP, batch experiments were performed based on OECD guideline 106, using three types of soils. Headspace solid‐phase microextraction (HS‐SPME) and GC‐MS were applied to the determination of OPP concentration in the liquid phase. The sorption isotherms obtained for all three soils under equilibrium conditions were described well, assuming linear sorption. The organic carbon normalized distribution coefficients (Koc) ranged from 894 to 1703 L kg?1, which suggested that OPP is moderately mobile in soil. The results also showed that the Koc value of OPP can be predicted precisely from Kow, whereas it was underestimated by one order of magnitude when water solubility is used. 相似文献