近年来灾害天气机理和预测研究的进展   总被引：4，自引：3，他引：4  

赵思雄  孙建华 《大气科学》2013,37(2):297-312

本文对近年来灾害天气机理和预测的研究成果作了简要的概述,涉及致洪暴雨、登陆台风、寒潮暴雪、强沙尘暴、高温酷暑等,紧密结合一些重大的极端天气事件展开分析.近年灾害天气频发,影响依旧十分严重.灾害天气多涉及各种尺度的系统以及它们之间的相互作用,加上气候变化,环流异常,中尺度系统活跃,使灾害天气的情况更趋复杂.本文对此作了探讨,并提出了一些需要面对和思考的问题,与大家切磋.  相似文献   

鄱阳湖湖泊流域系统水文水动力联合模拟   总被引：5，自引：5，他引：0  

李云良  张奇  姚静  李相虎 《湖泊科学》2013,25(2):227-235

本文以鄱阳湖湖泊流域系统为研究对象,鉴于该湖泊流域系统尺度较大,下垫面自然属性呈现高度空间异质性且具有流域-平原区-湖泊不同机制的水文水动力过程,为了真实描述湖泊流域间的水文水动力联系及反映不同过程间的作用机制,构建了鄱阳湖湖泊流域联合模拟模型.该模型基于自主研发的流域分布式水文模型WATLAC和湖滨平原区产流模型以及水动力模型MIKE 21 3个不同功能子模型的连接来实现该复杂系统的模拟.模型的联合采用输入-输出驱动及子模型的顺序执行进程,即将五大子流域与平原区入湖径流量作为输入条件来驱动湖泊水动力模型,模拟湖泊水位对流域入湖径流量的响应.以2000-2005年鄱阳湖流域6个水文站点的河道径流量、流域基流指数以及湖泊4个站点的水位资料来率定模型,其中各站点日径流量拟合的纳希效率系数E_ns为0.71~0.84,确定性系数R²介于0.70~0.88之间,而湖泊各站点水位拟合的纳希效率系数E_ns变化为0.88~0.98,确定性系数R²为0.96~0.98,均取得令人满意的率定结果.本文提出的鄱阳湖湖泊流域系统水文水动力联合模拟模型能较为理想再现湖泊水位对流域降雨-径流过程的响应.水位模拟结果进一步表明,该联合模型能用来获取重要的水动力空间变化特征.该模型可作为有效工具定量揭示湖泊流域系统水文水动力过程对气候变化和流域人类活动的响应.  相似文献   

气体水合物未来的能源   总被引：1，自引：0，他引：1  

张立生 《四川地质学报》1999,(1)

由水分子和甲烷等天然气体组成的笼形包合物气体水合物,是一种冰雪状的白色结晶物质,是新近发现的一种能源矿产,产出于大洋底的水下沉积物和陆上极地冻土带中。气体水合物是一种高密度的能源矿产,储量巨大,各大洋中都有,被称为２１世纪的能源,倍受各国政府和学者们的重视。  相似文献   

Geographic EducationResearch and the Changing Institutional Structure of American Education     

Fred M. Shelley 《The Professional geographer》1999,51(4):592-597

Professional geographers are paying increasing attention to the development of a research agenda concerning geographic education. In doing so, it is essential that geographers pay close attention to fundamental changes in the structure of education itself. Traditional educational methods and procedures associated with industrial society are being replaced by new and innovative modes of education that are linked to post-industrial social organization. This article explores the implications of these changes for understanding the teaching and learning of geography in the future.  相似文献   

新疆呼图壁21号泉动水位震兆特征   总被引：2，自引：0，他引：2  

高小其  许秋龙  杨马陵 《华南地震》2004,24(2):28-35

介绍了新疆呼图壁21号泉的水文地球化学环境,分析了该泉动水位变化的原因;总结了其震兆特征的变化规律,并对该泉的映震效能进行了评价。最后对其映震机理和映震性能较好的原因进行了探讨和分析。  相似文献   

SITE EVALUATION AND VOLCANIC HAZARD ASSESSMENT FOR THE NUCLEAR POWER PLANTS OF CHINA          下载免费PDF全文

XU Jian-dong  YU Hong-mei  ZHOU Ben-gang  CUI Wen-ling  DU Long  WEI Fei-xiang 《地震地质》2019,41(5):1289-1301

Starting from the 1980's of last century, China has launched the national plan of constructing nuclear power plants along the coastline region in eastern China. Currently, in some of these candidate sites, nuclear facilities have been installed and are in operation, but some other nuclear power plants are still under construction or in site evaluation. In 2012 the Atomic Energy Commission issued the specific guide for volcanic hazards in site evaluation for nuclear installations(IAEA Safety Standards Series No. SSG-21), which was prepared under the IAEA's program for safety standards. It supplements and provides recommendations for meeting the requirements for nuclear installations established in the safety requirements publication on site evaluation for nuclear installations in relation to volcanic hazards. To satisfy the safety standards for volcanic hazard, we follow the IAEA SSG-21 guidelines and develop a simple and practical diffusion program in order to evaluate the potential volcanic hazard caused by tephra fallout from the explosive eruptions. In this practice, we carried out a case study of the active volcanoes in north Hainan Province so as to conduct the probabilistic analysis of the potential volcanic hazard in the surrounding region. The Quaternary volcanism in north Hainan Island, so-called Qiongbei volcanic field is characterized by multi periodic activity, in which the most recent eruption is dated at about 4 000a BP. According to IAEA SSG-21, a capable volcano is one for which both 1)a future eruption or related volcanic event is credible; and 2)such an event has the potential to produce phenomena that may affect a site. Therefore, the Qiongbei volcanic field is capable of producing hazardous phenomena that may reach the potential nuclear power plants around. The input parameters for the simulation of tephra fallout from the future eruption of the Qiongbei volcanic field, such as the size, density and shape of the tephra, the bulk volume and column height, the diffusion parameter P(z), wind direction and intensity, were obtained by field investigation and laboratory analysis. We carried out more than 10000 tephra fallout simulations using a statistical dataset of wind profiles which are obtained from China Meteorological Data Sharing Service System(CMDSSS). Tephra fallout hazard probability maps were constructed for tephra thickness threshold of 1cm. Our results show that the tephra produced by the future large-scale explosive eruption from the Qiongbei volcanic field can affect the area in a range about 250km away from the eruption center. In summary, the current key technical parameters related to volcanic activity and potential hazards in IAEA/SSG-21 guidelines, such as 10Ma volcanic life cycle and 1×10^-7 volcanic disaster screening probability threshold, etc. are based on the volcanic activity characteristics in the volcanic island arc system. In consideration of the relatively low level of volcanic activity compared with volcanic island arc system due to the different tectonic background of volcanism in mainland China, the time scale of volcanic disaster assessment in IAEA SSG-21 guideline is relatively high for volcanoes in mainland China. We suggest that the study of "conceptual model" of volcanic activity should be strengthened in future work to prove that there is no credible potential for future eruptions, so that these volcanoes should be screened out at early stage instead of further evaluation by probabilistic model.  相似文献   

"海上丝绸之路"沿岸国家海洋综合风险分析与量化评估——以菲律宾为例     

洪梅  高正飞  曾文华  朱伟军  李明 《海洋通报》2019,38(3)

在"21世纪海上丝绸之路"重大战略构想的背景下,结合东盟国家对海上丝绸之路的重要作用。本文从海洋经济和海洋环境的角度对东盟国家存在的海洋综合风险进行评估分析,这对我国加强对东盟国家的认识,规避来自海洋方面的风险,更好地与其进行合作具有重要意义。主要针对东盟四国构建了评价海洋综合风险的指标体系;在此基础上,提出了基于改进的投影寻踪方法的海洋综合风险评估模型,以东盟四国中的菲律宾作为代表开展实验验证,最终得到菲律宾的海洋综合风险等级,并依据评级结果对我国与菲律宾的合作提供辅助建议。  相似文献   

Spectral characteristics of the nearshore waves off Paradip,India during monsoon and extreme events     

V. M. Aboobacker  P. Vethamony  K. Sudheesh  S. P. Rupali 《Natural Hazards》2009,49(2):311-323

Spectral and statistical wave parameters obtained from the measured time series wave data off Paradip, east coast of India during May 1996–January 1997 were analysed along with MIKE 21 spectral wave model (SW) results. Statistical wave parameters and directional wave energy spectra distinctly separate out the wave conditions that prevailed off Paradip in the monsoon, fair weather and extreme weather events during the above period. Frequency-energy spectra during extreme events are single peaked, and the maximum energy distribution is in a narrow frequency band with an average directional spreading of 20°. Spectra for other seasons are multi-peaked, and energy is distributed over a wide range of frequencies and directions. The NCEP re-analysis winds were used in the model, and the results clearly bring out the wave features during depressions. The simulated wave parameters reasonably show good match with the measurements. For example, the correlation coefficient between the measured and modelled significant wave height is 0.87 and the bias −0.25.  相似文献   

21世纪海上丝绸之路战略构架下中国-肯尼亚海洋合作之探讨          下载免费PDF全文

徐静静  谭攻克 《海洋开发与管理》2018,35(5):10-13

21世纪海上丝绸之路战略是新时期我国重要的对外战略,加强与沿线国家在海上的务实合作是21世纪海上丝绸之路建设的重要内容。文章通过探讨21世纪海上丝绸之路战略对海上合作在合作原则、合作思路及合作重点等方面提出的要求,分析我国21世纪海上丝绸之路建设重要据点——肯尼亚的战略优势及海洋优势,提出中国与肯尼亚海洋合作应从推动双方海洋科研院所之间建立合作机制、建设中肯海洋渔业联合研究中心、资助联合研究项目的开展、加强双方人员交流,扩大青年科学家培训规模、加强双方在海洋非传统安全领域的合作5个方面重点推进的建议,为今后中-肯海洋合作指明方向。  相似文献   

“21世纪海上丝绸之路”航运服务业网络格局研究   总被引：1，自引：0，他引：1  

王列辉  张楠翌  朱艳 《地理科学》2020,40(10):1663-1670

在“一带一路”倡议下，发展航运服务业对于巩固与提升中国在全球航运网络中的地位具有重要意义。构建103家跨国公司在“21世纪海上丝绸之路（海丝之路）”沿线1 054个城市的分布数据库，分析7种航运服务业在“海丝之路”沿线的网络特征。研究表明：① “海丝之路”沿线航运服务业网络的层级分布特征明显，处于第一层级的均为亚洲城市，说明亚洲航运服务业在航运服务业网络中地位重要。② 在“海丝之路”这一层面，伦敦、香港、新加坡等城市和地区构成大的联系三角，在中国层面，上海、香港、北京构成小的联系三角。③ 高端航运服务业主要分布在欧洲城市，亚洲城市在中端航运服务业方面占据重要地位，在低端航运服务业方面，非洲城市在仓储服务业表现突出，亚洲和欧洲城市则在船舶修造业实力雄厚。④ 高端航运服务业往往受城市的历史、文化、语言、法律、制度影响较大，对地方的根植性较强，倾向于首都等内陆城市，而中低端航运服务业主要依托于货物运输，受自然条件和区位条件等因素的影响较大，往往随货物运输转移而转移，倾向于分布在港口城市。  相似文献