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《Climate Policy》2001,1(3):309-326
Carbon dioxide emissions from UK energy use have fallen by more than 20% over the last 30 years, and carbon intensity — carbon emissions per unit of GDP — has halved. These reductions have been achieved by a combination of decarbonisation of the energy system and substantial improvements in energy efficiency. Use of natural gas in power generation has been a big factor in recent years, but energy efficiency improvements in households and particularly industry have been more important over a longer period. Government policies designed primarily to address climate change have not been important contributors, until recently.Future reductions in emissions will require more proactive policies. However, they are possible without any economic difficulties, notably by adopting cost-effective energy efficiency measures, using new renewable energy sources and reducing dependence on private cars. These policies will improve economic efficiency. The new UK Climate Change Programme includes policies that combine regulation, investment, fiscal measures and other economic instruments. By working with the grain of other social, environmental and economic policies, they can achieve far more than a carbon tax alone, set at any politically acceptable level. Modelling the costs of emission reductions using a carbon tax as the only instrument would not only massively over-estimate costs, it would bear little resemblance to real world politics.The paper demonstrates that a more diverse set of policy instruments is likely to be an effective and politically acceptable approach in a mature industrial economy. It is concluded that the UK’s Kyoto target of a 12.5% reduction in greenhouse gas emissions is not challenging. The UK Government’s target of reducing carbon dioxide emissions by 20% between 1990 and 2010 is also achievable. By 2010 per capita emissions from the UK will be well below 2.5 tC per year. Claims that some countries, notably the USA, could not reduce per capita emissions below 6 tC per year seem inconsistent with this experience. 相似文献
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The relationship between summer rainfall anomalies in northeast China and two types of El Ni?o events is investigated by using observation data and an AGCM. It is shown that, for different types of El Ni?o events, there is different rainfall anomaly pattern in the following summer. In the following year of a typical El Ni?o event, there are remarkable positive rainfall anomalies in the central-western region of northeast China, whereas the pattern of more rainfall in the south end and less rainfall in the north end of northeast China easily appears in an El Ni?o Modoki event. The reason for the distinct differences is that, associated with the different sea surface temperature anomalies (SSTA) along the equatorial Pacific, the large-scale circulation anomalies along east coast of East Asia shift northward in the following summer of El Ni?o Modoki events. Influenced by the anomalous anticyclone in Philippine Sea, southwesterly anomalies over eastern China strengthens summer monsoon and bring more water vapor to Northeast China. Meanwhile, convergence and updraft is strengthened by the anomalous cyclone right in Northeast China in typical El Ni?o events. These moisture and atmospheric circulation conditions are favorable for enhanced precipitation. However, because of the northward shift, the anomalous anticyclone which is in Philippine Sea in typical El Ni?o cases shifts to the south of Japan in Modoki years, and the anomalous cyclone which is in the Northeast China in typical El Ni?o cases shifts to the north of Northeast China, leading to the “dipole pattern” of rainfall anomalies. According to the results of numerical experiments, we further conform that the tropical SSTA in different types of El Ni?o event can give rise to observed rainfall anomaly patterns in Northeast China. 相似文献
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中国降水异常的特征分析 总被引：9，自引：0，他引：9
异常降水直接影响着农业和其他生产活动。文中计算分析了中国160个测站的一些反映降水变化的常规统计量,认为这些统计量难以反映出降水异常的变化特征。文中从非线性动力学和统计学相结合的角度出发,分析了相隔1～20 a间不同时间尺度的降水变率之间的关系,找到可以区分任意地区降水异常特点的特征参数,由此可进一步判断某个地区旱涝灾害发生的可能性以及强度的大小,为气候研究工作提供必要的依据。 相似文献
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本文利用中国气象科学数据共享服务网提供的中国地面降水日值0.1°×0.1°格点数据集(V2.0)、FY-2E逐小时红外黑体辐射亮温(Temperature of Black Body,以下简称TBB)资料和欧洲中心ERA-Interim0.5°×0.5°,6小时一次温度、风场、位势高度、相对湿度等资料对2012年7月21~22日一次四川暴雨进行了初步分析。结果表明,西南低涡活动为此次四川盆地强降水过程提供了有利的发生条件。在此基础之上,副热带高压引导的暖湿空气与西伯利亚南下的冷空气相汇于四川盆地,风切变的生成,大量不稳定能量在四川盆地东部累积,和盆地上空形成的上升气流,为此次降水过程提供了有利的天气条件。随着西南低涡的东移减弱,四川盆地此次降水过程也随之结束。 相似文献
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利用广汉机场2010~2014年遥测地面风场资料,分析了春季地面风的年变化、月变化以及日变化特征,讨论了地面风对飞行训练的影响。结果表明:广汉机场春季盛行偏北风,此外主要还受到北西北、北东北风的影响,飞行训练易遭遇左侧风;4~5m/s以及6m/s以上的地面风日数年变化不大,但春季最大风速的年变化差异较大;3~5月月平均地面风速呈递增特征,从3月到5月主导风向由北风顺时针变化为东北风,东东南、东南、南东南风频率逐渐增加,左侧风以及逆风影响增大。地面风速的日变化呈现出“一峰一谷”的大陆型变化特征,即白天风速大,夜间风速小,午后风速最大,4~5m/s的风受日变化影响大,6m/s以上的风主要受天气系统的影响。 相似文献
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以2010、2015、2019年冬春航季我国客运航空网络为研究对象,采用标准差椭圆与复杂网络相关指标,对指标进行反距离权重法插值,分析十年来我国客运航空网络空间结构演化特征。发现：1）从机场空间来看,西部地区机场数量处于相对增长状态,同时西北机场群布局中心向西北方向移动,而其余五大机场群布局稳定,使得机场布局中心逐渐西移,有均衡布局趋势;2）从航线网络来看,规模增长迅速,由于高度值节点地位稳定,低度值节点占比减少,使得度分布集聚性增加,另外网络运输效率与节点可达性呈增长趋势,平均度值附近高聚类系数节点增加,网络层级加强,但网络小世界特征有所减弱;3）从节点中心性来看,成都、西安、重庆3个城市接近中心性与介数中心性增加明显,在网络中的价值与控制力得到提升,网络中介枢纽向内陆演化。 相似文献