ERS-2 SAR反演海洋风矢量的研究   总被引：4，自引：0，他引：4       下载免费PDF全文

陈艳玲  黄珹  丁晓利  李志伟 《地球物理学报》2007,50(6):1688-1694

SAR(Synthetic Aperture Radar)反演海洋风矢量是当今微波遥感领域非常有意义的前沿课题. 本文首先介绍了星载SAR估算海面风向、风速的基本原理和三种主流反演算法,接着给出反演的流程图以及重要步骤. 然后,以2002年5月7日香港地区ERS-2 SAR海洋图像为例,对经典的SWDA (SAR Wind Direction Algorithm)－谱分析方法加以改进,求得具有180°模糊度的风向,并用香港天文台气象浮标实测数据消除了风向不确定性. 最后,利用CMOD4 GMF（Geophysical Model Function,地球物理模式函数）计算得到海面上10m高的风速. 与气象浮标站实测资料相比,利用ERS-2 SAR图像获取的海面风向、风速的精度均较高. 这一结果表明：如果对SAR预先进行ADC(Analog to Digital Converter)改正以及精确校准,结合改进的SWDA和CMOD4,可以获得高精度的风矢量.  相似文献   

南昌市环境空气臭氧污染现状分析   总被引：2，自引：0，他引：2  

万志勇  杨辛 《气象与减灾研究》2007,30(2):69-72

利用南昌市省外办环境空气监测点2003—2006年臭氧监测资料,使用综合污染指数法和国家《环境空气质量标准》进行分析评价。分析结果表明,南昌市省外办监测点环境空气中臭氧污染已经达到一定程度,2006年臭氧年日均值达0.203 mg/m3,年日均值超标率为12.63%;臭氧污染指数为2.03,污染负荷高达53.88%,比目前最为关注的污染物(可吸入颗粒物)污染负荷高39.07%。臭氧已成为城市环境空气中的主要污染物之一,尤其是每年的9月和10月,其污染更为严重。建议全省各城市积极创造条件开展环境空气臭氧监测,并纳入必测项目参加评价;环保部门应加强与气象部门的合作,科学分析江西环境空气臭氧污染原因,提出防治措施。  相似文献   

清咸丰六年长江三角洲地区旱灾气候背景分析   总被引：3，自引：2，他引：1  

杨煜达 《气象与减灾研究》2007,30(3):26-30

介绍了清咸丰六年(1856年)长江三角洲地区大旱的发生情况,认为此次大旱持续时间长,属夏秋连旱;旱情严重,波及面广,几乎影响到了长江三角洲的所有地区,太湖流域北部、南部,江北淮南地区最严重,太湖东部的苏州、松江二府、太仓直隶州的灾情略轻,江北东部的通州直隶州灾情也较轻,最东边的海门直隶厅甚至没有找到大灾的明确记载。大旱之后继发了大蝗灾。在此基础上,对引发此次严重干旱的气候背景进行了分析。分析结果认为,副热带高压强度偏弱,但脊线位置偏北,造成了季风雨带偏北,长江三角洲地区长时间处在副高控制下,从5月底至8月底没有出现连续性降水,造成了罕见的大旱;而春季降水不足,又加剧了灾情。  相似文献   

浙江中西部一次大范围降水过程的多普勒雷达资料分析     

周良女  汤达章  苏来琪  余春林 《气象与减灾研究》2007,30(1):37-40,F0003

运用多普勒天气雷达和天气图资料,对2006年7月6日出现在浙江中西部的1次大面积强降水过程进行了分析,探讨了多普勒天气雷达资料在大面积降水过程中的图像特征。发现在不同的降水时段,垂直风廓线(VWP)产品和径向速度PPI图像都表现出非常明显的特征。利用EVAD技术和变分法计算的散度和垂直速度产品,能比较直观地反映这次过程中大气各层辐合、辐散和垂直运动情况,并以此对浙江大面积降水过程发生、发展、维持和消亡的动力学机制进行了探讨。  相似文献   

冷空气侵入的暴雨过程物理量场变化与诊断分析   总被引：1，自引：0，他引：1  

罗冰 《气象与减灾研究》2007,30(1):24-29

通过对近年的几次有低层冷空气侵入的暴雨天气过程进行数值模拟和诊断分析,发现很多暴雨天气过程都与冷空气侵入有密切关系,连续暴雨过程是在较好的水汽条件和不稳定层结条件下发生的,K指数、Q矢量辐合、螺旋度、水汽通量辐合、涡度和上升速度等物理量大值区的范围和演变趋势,同暴雨范围及演变趋势基本一致;暴雨区上空有高位涡柱存在,并有自低层到高层的高位涡上传。  相似文献   

辽宁能源水资源与环境问题探讨   总被引：3，自引：0，他引：3       下载免费PDF全文

靳君 《气象与环境学报》2006,22(5):50-52

在分析辽宁能源状况和水资源量与分布状况及生态环境现状的基础上,揭示了经济发展与生态环境方面存在的矛盾,针对辽宁的能源利用率低、水环境安全受到威胁、区域环境污染集中等问题,结合辽宁实际情况,对此进行了探讨并提出了对策与建议。  相似文献   

Neoliberal energy transitions in the South: Kenyan experiences     

《Geoforum》2016

What is the relationship between the direction and form of an energy transition and the political economy within which it is embedded? This paper explores how the nature of (low carbon) energy transitions is strongly influenced by the process of neoliberalisation that shape energy policy in the South. We seek to understand emergent energy transitions and to advance their theorisation through an account of the political economy of energy transition in Kenya. In contrast to the often techno-managerial orientation of literatures on socio-technical transitions, we explore the political terrain upon which competing visions of energy futures and material interests collide and seek to accommodate one another. We develop a political economy account that emphasises the structural and disciplinary power of capital and global institutions to set the terms of transition. This expresses itself in both delimiting the autonomy of state actors and by reconfiguring domestic institutional and social power in ways that shape the distributional politics of transitions.  相似文献   

Regional evapotranspiration rate of oasis and surrounding desert     

Jihong Jia  Wenzhi Zhao  Shoubo Li 《水文研究》2013,27(24):3409-3414

The surface energy balance algorithm for land method was used in this study to calculate the evapotranspiration (ET) rate for the middle reaches of the Heihe River Basin, Gansu Province, China, to analyse ET distribution within the oasis and the surrounding desert and, especially, on the edge zone of the oasis. Five profile graphs were created vertical to the river. Because of the inverse humidity phenomenon, the least amount of evapotranspiration occurred on the desert close to the oasis. The average evapotranspiration rate was roughly proportioned from the edge of the oasis to inside and outside its boundary. Two meteorological ground stations located close to the oasis edge showed a notable difference in net radiation flux that led to the difference found in ET. The primary reason for the significant differences observed in net radiation may be largely the result of differences in flux reflectivity and surface temperature. Meteorological data show that water supply also played an important role. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

Governance and technology transfer in the Clean Development Mechanism in India     

Jon Phillips  Kasturi Das  Peter Newell 《Global Environmental Change》2013,23(6):1594-1604

Despite significant technological advances in emerging economies, the further development of clean energy technologies in developing countries remains crucial to reducing the greenhouse gas emissions associated with economic development. In this paper we address two significant gaps in the growing body of literature that has assessed the role of the Clean Development Mechanism in promoting the transfer of clean technologies to developing countries. First, we present a qualitative analysis of the governance of the Clean Development Mechanism in India. This provides a basis for understanding the extent to which and the ways in which governance may impact upon the likelihood that projects promote technology transfer. Second, we provide a novel quantification of the level and nature of technology transfer that has occurred in Indian Clean Development Mechanism projects, based on insights from literature on technological capability building. We find that the Clean Development Mechanism in India has produced a negligible number of projects that promote technology transfer if technology transfer is understood as a process of learning about technology. Together these qualitative and quantitative analyses show how politics and governance have contributed to the current form of the Clean Development Mechanism market in India, in which processes of building indigenous technological capabilities have been neglected.  相似文献   

ICP—AES法分析辉锑矿   总被引：1，自引：0，他引：1  

曾惠芳 《岩矿测试》1990,9(2):93-99

本文针对辉锑矿成分复杂、主元素Sb易水解、部分元素易挥发,酸不溶元素的存在以及元素之间的干扰等问题,拟定了酸溶和碱熔分解试样的分析流程。在酸溶系统中结合TBP萃淋树脂和巯基棉分离富集分组,ICP-AES法测定Fe、Ca、Mg、Cu、Mn、Pb、Zn、Co、Ni、Au、Ag、In、Tl、Cd、Bi、Ga、Mo、Se、Te、As等20个元素。碱熔系统不分离主元素,用校正因素校正元素间光谱干扰并采用内标法ICP-AES测定Al、Ti、V、Ba、Sr、Sn、Sc、Cr、Be、Si和Sb等11个元素。试样验证表明,方法可行。  相似文献