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381.
西北太平洋热带气旋迅速增强特征及其影响因子   总被引:2,自引:1,他引:2  
选取西北太平洋上热带气旋(TC)24小时风速变化累积频率达95%所对应的15.4 m/s作为迅速增强(RI)的标准,研究了RI个例的基本特征以及TC自身特征因子与环境因子对RI的作用。结果表明,TC迅速增强过程的持续时间平均为33小时,最长可达78小时,并且TC经过迅速增强过程几乎都达到了台风级别以上,其中,一半以上达到了强台风级别以上。对比迅速增强(RI)和非迅速增强(non-RI)个例得到,RI个例相对于non-RI个例发生区域偏南偏东,两者的移动速度没有明显差异,但RI个例有较大向西移动分量并且前12小时增强较大;相对于non-RI个例,RI个例离最大潜在强度较远并且发生在较暖水区和55%~75%的低层相对湿度的条件下;RI个例发生在较小的垂直风切变和较弱的对流层上层东风气流情况下,由上层槽或冷低压引起的强迫弱于平均状况时RI较易发生。TC前12小时强度变化(DVMX)、海表面温度(SST)和垂直风切变(SHR)是影响迅速增强的主要因子,当DVMX≥6.3 m/s时RI发生的可能性最大,达到17.2%。当有若干个影响因子共同起作用时发生RI可能性显著增加,其中以较大的前12小时强度变化(DVMX≥6.3 m/s)、较高的海表面温度(SST≥29.4℃)、较弱的垂直风切变(SHR≤5.9 m/s)、较小的相对涡旋角动量通量辐合(REFC≤-1.6 m/(s.d))、偏东经度(LON≥138.2°E)和低纬度(LAT≤16.7°N)共同作用时,RI发生的可能性达到最大,可达66.7%。  相似文献   
382.
基于手机短信的地震灾情速报平台,是尽可能利用现有的移动通信网络和基层单位覆盖面齐全的特点快捷完成灾情收集。在全省范围内的每个乡镇培训出3~5名手机短信灾情速报员,在破坏性地震发生时,省局应急指挥中心迅速给这些人员发送灾情收集指令,灾区的速报员按照所收到短信的提示逐步展开排查确定灾害等级,然后将灾情等级代码反馈给省级地震应急指挥中心,灾情速报平台自动处理收集的短信,最后按灾区的受灾轻重程度在地图上表示出来。  相似文献   
383.
无锡市地震速报信息智能发布系统的研制与应用   总被引:1,自引:0,他引:1  
建设地震速报信息智能发布系统,是把EQIM速报信息共享服务系统、地震信息自动发布平台、发布子平台等实现一体化集成。系统建成后,实时获取各类地震速报结果、自动规范生成多种类型的地震信息,实现地震速报信息的规范、实时、多手段智能发布。通过扩展发布服务、对接地震信息数据,提高信息发布的及时性、准确性和多样性。  相似文献   
384.
结合2009年1月1日起正式执行的《国家速报台站大地震速报评比标准》的要求,对太原基准地震台2009年速报工作中存在的主要问题进行了总结分析,对如何改进工作,有效提高速报质量,提出了改进措施。  相似文献   
385.
通过对乌鲁木齐地震台宽频带数字地震仪记录的具有代表性、典型性的地震波形震相分析,展示乌鲁木齐地震台宽频带数字地震仪记录波形震相特征,找出快速判定震相的方法,进一步提高大震速报质量。  相似文献   
386.
Unstable fault deformation and information synthesis   总被引:2,自引:0,他引:2  
UnstablefaultdeformationandinformationsynthesisWAN-JUBO(薄万举),JUE-MINXIE(谢觉民)andGUAN-SHOULOU(楼关寿)FirstCrustalDeformationMonit...  相似文献   
387.
Earthquake detection and location are essential in earthquake studies, which generally consists of two main classes: waveform-based and pick-based methods. To evaluate the ability of two different methods, a graphics-processing-unit-based Match & Locate (GPU-M&L) method and a rapid earthquake association and location (REAL) method are applied to continuous seismic data recorded by 24 digital seismic stations from Jiangsu Seismic Network during 2013 for comparison. GPU-M&L is one of waveform-based methods by waveform cross-correlations while REAL is one of pick-based method to associate arrivals of different seismic phases and locate events through counting the number of P and S picks and travel time residuals. Twenty-six templates are selected from the Jiangsu Seismic Network local catalog by using the GPU-M&L. The number of newly detected and located events is about 2.8 times more than those listed in the local catalog. We both utilize a deep-neural-network-based arrival-time picking method called PhaseNet and a short-term/long-term average (STA/LTA) trigger algorithm for seismic phase detection and picking by applying the REAL. We then refine seismic locations using a least-squares location method (VELEST) and a high-precision relative location method (hypoDD). By applying STA/LTA and PhaseNet, 1006 and 1893 events are associated and located, respectively. The newly detected events are mainly clustered and show steeply dipping fault planes. By analyzing the performance of these methods based on long-term continuous seismic data, the detected catalogs by the GPU-M&L and REAL show that the magnitudes of completeness are 1.4 and 0.8, respectively, which are smaller than 2.6 given by the local catalog. Although REAL provides improvement compared with GPU-M&L, REAL is highly dependent on phase detection and picking which is strongly affected by signal-noise ratio (SNR). Stations at southeast of the study region with low SNR may lead to few detections in the same area.  相似文献   
388.
Groundwater ridging is the rapid rise of a shallow water table during a rainfall event, in an environment where, in the pre‐event period, the capillary fringe extends to the ground surface. Groundwater ridging is widely cited to account for the observed significant appearance of pre‐event water in a stream stormflow hydrograph. Various hypotheses have been advanced to explain the groundwater‐ridging mechanism; and most recently, from a field study site in South Africa, an energy hypothesis was proposed, which explains that groundwater‐ridging water‐table rise is a result of rapid introduction and transmission of additional pressure head into the capillary fringe from an intense rainfall at the ground surface. However, there is a need for further analysis and evidence from other field study sites to confirm and support this newly proposed energy hypothesis. The objectives of this paper are, therefore, as follows: to review previous observations on groundwater ridging, from other study sites, in order to deduce evidence of the newly proposed energy hypothesis; to present and evaluate a one‐dimensional diffusion mathematical model that can simulate groundwater‐ridging water‐table rise, based on the newly proposed energy hypothesis; and to evaluate the importance of a capillary fringe in streamflow generation. Analysis of previous observations from other study sites generally indicated that the rate of groundwater‐ridging water‐table rise is directly related to the rainfall intensity, hence confirming and agreeing with the newly proposed energy hypothesis. Additionally, theoretical results by the mathematical model agreed fairly well with the field results observed under natural rainfall, confirming that the rapidly rainfall‐induced energy is diffusively transmitted downwards through pore water, elevating the pressure head at every depth. The results in this study also support the concept of a three‐end‐member stream stormflow hydrograph and contribute to the explanation of how catchments can store water for long periods but then release it rapidly during storm events. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
389.
依据陕西地震台网速报信息发布流程,以及地震速报信息向地市地震网站发布的实际情况,利用"十五"门户网站管理软件,在技术上探讨了地震速报信息向市县级地震网站快速发布的三种方式.  相似文献   
390.
山西数字地震台网地震自动定位系统运行分析   总被引:1,自引:0,他引:1  
选取2009年7月至2010年8月山西地震台网速报软件的自动定位结果与"十五"Jopens系统人机交互处理的定位结果进行对比分析,得出,速报软件自动定位地震参数与人机交互处理的编目结果基本吻合,可以作为地震速报的依据和参考。  相似文献   
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