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51.
The European Commission as a whole and a number of its Member States individually have adopted a stringent long-term target for climate policy, namely that the global mean temperature should not rise more than 2 °C above pre-industrial times. This target is supported by rather thin arguments, based on inadequate methods, sloppy reasoning, and selective citation from a very narrow set of studies. In the scientific literature on “dangerous interference with the climate system”, most studies discuss either methodological issues, or carefully lay out the arguments for or against a particular target. These studies do not make specific recommendations, with the exception of cost-benefit analyses, which unanimously argue for less stringent policy targets. However, there are also a few “scientific” studies that recommend a target without supporting argumentation. Overall, the 2 °C target of the EU seems unfounded. 相似文献
52.
The purpose of this paper is to analyze the costs for reducing CO2 emissions in the power-generating sectors in Croatia, the European part of Russia, Macedonia, Serbia and the Ukraine in 2020 by using a linear programming model. The model takes into account the impact of technology learning and is based on the underlying assumptions of the so-called RAINS model frequently used to assess the potential and the costs for reducing air pollution in Europe. The results based on an exogenously given 15 percent reduction target for CO2 emissions show that the marginal cost for switching from a carbon-intense fuel to either a low-carbon or to a renewable energy source differs significantly among the countries. The marginal costs range from 4 to 90€ per ton CO2, and are mainly due to country differences in the availability of renewables, existing technologies and costs. The results also indicate that although it is clear that the Eastern European countries are not homogeneous in terms of CO2 abatement potential and costs, no general conclusions can be made of the region. This may have important implications for future JI/CDM activities. For instance, risk factors such as policy uncertainty and institutional obstacles may become crucial in determining the future allocation of JI/CDM projects across the region. 相似文献
53.
辽宁省不同地区发展日光温室适宜性分析 总被引:6,自引:0,他引:6
温度和光照是影响日光温室环境的主要因素,结合辽宁省农业气候资源的地域特点,对辽宁省不同地区发展日光温室的适宜性进行简要评价,并提出了不同地区发展适宜性建议。 相似文献
54.
Development of global electric generation and distribution systems will be central to mankind's economic and social well being. However, electricity is likely to be produced mainly from fossil fuel combustion for the foreseeable future. As a consequence, this global energy sector will contribute to growing carbon dioxide emissions, with a potential for climate alteration. Concern for potentially adverse climate effects has led to consideration of strategies for managing GHG emissions. With present technologies, extreme reduction strategies will be costly and may create significant stress on the projected world economic and energy systems. Technological options have been evaluated to a modest degree. These range from conventional emission control approaches to geo-engineering opportunities and biospheric carbon management. To be practical, these options need to be developed further and demonstrated to properly assess their operational characteristics. 相似文献
55.
In this study, energy rating of different window glazings, available in the Indian market, has been carried out. This rating is helpful in selecting the best window for a given building and a given climate. It is shown that savings by a window w.r.t. the base window (single glazed, clear glass, 6 mm thick), depend upon window type, its orientation, climatic conditions of the place, buildings dimensions and thermal transmittance of its walls and roof. The study has been performed for five different climatic zones of India. Ten types of windows have been studied which include clear glass, tinted glass, low-e coated and solar control windows. Three types of buildings are considered with U-value of their walls ranging 0.52–2.07 W/m2K and U-value of their roof ranging 0.54–2.34 W/m2K. Finally, regression analysis is performed to develop energy rating equations for different glazings, buildings and climates. 相似文献
56.
Assessing the natural ventilation cooling potential of office buildings in different climate zones in China 总被引:1,自引:0,他引:1
This paper presents an investigation of the natural ventilation cooling potential (NVCP) of office buildings in the five generally recognised climate zones in China using the Thermal Resistance Ventilation (TRV) model, which is a simplified, coupled, thermal and airflow model. The acceptable operative temperature for naturally conditioned space supplied by the ASHARE Standard 55-2004 has been used for the comfort temperature setting. Dynamic simulations for a typical office room in the five representative cities, which are Harbin, Beijing, Shanghai, Kunming and Guangzhou, have been carried out. The study demonstrates that the NVCP depends on the multiple impacts of climate, the building's thermal characteristics, internal gains, ventilation profiles and regimes. The work shows how the simplified method can be used to generate detailed, indoor, operative temperature data based on the various building conditions and control profiles which are used to investigate the NVCP at the strategic design stage. The simulation results presented in this paper can be used as a reference guideline for natural ventilation design in China. 相似文献
57.
壮族是干栏式建筑的主要发明者和干栏文化的主要创造者。黑衣壮是壮族传统文化的活化石,其民居中蕴含的低技术被动式的原生态建筑设计策略符合我国国情,具有现实的指导意义。本文在对实地进行详细调研基础上,从原生态策略的角度对其设计思想和设计手法进行分析,并对其原生态的设计策略在当代建筑设计中的延续与发展进行了探讨。 相似文献
58.
59.
Large lakes have an impact on regional weather. In addition, they can be both sensitive to and influence regional climate changes. In the climate models that are used to investigate future climate changes, lakes are greatly simplified and sometimes absent. At the regional scale, this can have strong implications for the quality of the model information about the future. Through our work with climate information users in the Laurentian Great Lakes region, we have found that basic credibility of the information requires the underlying climate models simulate lake-atmosphere-land interactions. We are not aware of efforts within the scientific community to make known how individual large lakes are represented in models and how those representations translate to the quality of the data for particular regions. We share our framework for identifying how the Laurentian Great Lakes are represented in the Coupled Model Intercomparison Project (CMIP) version 5 climate models. We found that most CMIP5 models do not simulate the Great Lakes in a way that captures their impact on the regional climate, which is a credibility issue for their projections. We provide a perspective on the usability of CMIP5 for practitioners in the Great Lakes region and offer recommendations for alternative options. 相似文献
60.
Typhoon Aere in 2004 induced severe sedimentation and loss of storage capacity of the Shihmen Reservoir in northern Taiwan. The resulting dramatic increase in the turbidity of the water seriously affected the water supply. To effectively maintain the stability of the water supply and maintain the reservoir’s storage capacity, the government of Taiwan began to plan and construct a series of improvement measures, such as a sediment flushing tunnel, the JhongJhuang Bank-Side Reservoir, and the Amuping Desilting Tunnel. However, previous studies only focused on the impact of the sediment flushing tunnel and the Amuping Desilting Tunnel on the downstream riverbed, and did not consider the possibility of increasing sediment discharge after the completion of the JhongJhuang Bank-Side Reservoir. In addition, climate change will cause the intensity of extreme rainfall to increase enormously in the future. That rainfall and extra sediment flushing will challenge the existing flood prevention facilities. Therefore, this study considered that the JhongJhuang Bank-Side Reservoir will increase sediment discharge of the Shihmen Reservoir, and used dynamical downscaling extreme typhoon data of climate change under the RCP 8.5 scenario to explore the flood prevention and riverbed migration of the main channels of the Dahan and Tamsui Rivers in the future. We used the rainfall–runoff model of Hydrologic Modeling System to simulate rainfall and runoff, and used the hydraulic and sediment transport model of CCHE1D to holistically simulate flood events and consequent river scouring and deposition behaviors. Our results showed that the projected peak discharge during the late 21st century (2075 to 2099) will be at least 50% higher than that during the baseline (1979 to 2003) period. In terms of flood prevention, the potential of overbank flooding will increase in the downstream area, and the trend of long-term change in the riverbed will be dominated by degradation (-0.489 ± 0.743 m) in the future. The improvement measures will have a limited impact on riverbed migration (0.011 ± 0.094 m) in the Dahan and Tamsui Rivers. After the operation of the JhongJhuang Bank-Side Reservoir, the Shihmen Reservoir is expected to increase the sediment discharge ratio by 70% during floods, and it will not cause excessive water turbidity that may affect downstream water supply. 相似文献