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郄秀书 袁善锋 陈志雄 王东方 刘冬霞 孙萌宇 孙竹玲 Abhay SRIVASTAVA 张鸿波 卢晶雨 肖辉 毕永恒 冯亮 田野 徐燕 蒋如斌 刘明远 肖现 段树 苏德斌 孙成云 徐文静 张义军 陆高鹏 Da-Lin ZHANG 银燕 余晔 《中国科学:地球科学》2021,(1)
在国家"973"项目"雷电重大灾害天气系统的动力-微物理-电过程和成灾机理"(简称:雷暴973)资助下,2014~2018年连续五年在北京组织开展了雷电(也称闪电)灾害天气系统的暖季综合协同观测实验,旨在获得对北京及周边城市群区域的雷电天气系统特征和规律的实际认识,探索雷电资料在数值预报模式中的同化方法,以期改进雷电重大灾害天气系统的预报效果.主要观测设备包括:由16个子站构成的雷电(全闪)三维定位系统、2台X波段双线偏振多普勒雷达和4台激光雨滴谱仪等,协同观测还充分利用了中国气象局在京津冀地区的中尺度气象观测网.观测结果表明,受地形和环境条件影响,飑线和多单体雷暴是影响北京地区的两类主要的雷电灾害天气系统,它们除产生频繁的雷电活动外,还常伴随突发性局地短时强降水和冰雹,造成城区突发洪涝灾害.雷电密度的高值区位于北京昌平区东部、顺义区的中部和东部以及中心城区.超强雷暴(占总雷暴数的5%)、强雷暴(占比35%)和弱雷暴(占比60%)对总雷电分布的贡献分别为37%、56%和7%.北京城区的热岛效应对过境雷暴增强产生了重要作用,超强雷暴在中心城区的雷电频数可以高达每分钟数百次.雷电活动与雷暴云的热动力、微物理特征之间存在紧密联系,因此雷电频数可以作为冰雹、短时强降水等灾害性天气的指示因子.在对流可分辨数值预报模式中,建立并引入雷电资料同化方案,通过调整或修正模式的热动力和微物理参量,可明显提高模式对强对流和降水的预报效果. 相似文献
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热带气旋背景条件下的城市效应与广州夏季雷暴 总被引：1，自引：0，他引：1
利用广州地区中尺度自动气象站观测网资料、广州雷达回波资料以及卫星TBB资料等, 分析了2005年8月初受热带气旋外围气流影响条件下广州地区“城市热岛”(UHI)的演变特征, 并主要对期间8月4日夜间和7日午后发生在广州城区的两次雷暴过程及其与UHI等城市效应的关系进行了研究. 结果发现两次雷暴的形成均与UHI相关, UHI引起局地气流发生辐合并引发对流发展, 对流降水发生的时间和位置均与UHI的演变及其相应的辐合区有良好对应关系, 对流易于在UHI发展较强的时段和位置上发生. 而且受城市的影响, 两次雷暴在移动经过广州城区时均得到了进一步发展, 最强的对流回波出现在中心城区上空, 降水也集中落在中心城区. 所有这些特征表明两次雷暴的形成和发展均与城市的影响有关. 相似文献
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2016年4月19日云南地区爆发了一次强飑线天气,并相继对楚雄和昆明台的洞体应变观测产生了显著干扰.那么其扰动的全貌和机制究竟如何?截止目前,还鲜有研究.有鉴于此,本文结合多普勒天气雷达和地面气象观测要素数据,对楚雄和昆明台洞体应变的响应历程进行了深入分析.结果表明：(1)飑线过境时的“雷暴鼻”是洞体应变呈脉冲状张性变化的主因,由此产生的最大应变量为19.04×10-9;(2)各台洞体应变的扰动形态与“雷暴鼻”高度相似,说明其台基岩体均能以线弹性变形的方式响应飑线过程中的气压剧变;(3)“雷暴鼻”中周期性气压的能量主要集中在8～20 cpd频段内;(4)洞体应变对“雷暴鼻”的响应存在一定的相位超前现象.以上结果,不单有助于辨识云南地区洞体应变时序曲线中飑线噪声,而且还能为高频段气压效应的精确改正等提供观测证据. 相似文献
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地震前兆数字化仪器受到强雷暴干扰研究 总被引：4，自引：2，他引：4
邱永平 《地震地磁观测与研究》2003,24(5):100-105
引言 随着科学技术的不断进步,我国的地震监测仪器设备也从模拟观测时代进入了数字观测时代。然而,自动化数字观测仪器不同于传统的手动模拟观测仪器,它对安全供电要求很高,如大的电压波动、瞬间的强雷暴干扰等都会对仪器的连续稳定工作产生较大的影响,甚至毁坏仪器。因此,在数字化观测仪器设备安装之前,一般都进行供电、通信、地线、避雷等观测环境条件的改造,以确保仪器能够正常工作,取得连续、稳定、及时、可靠的观测资料,为地震监测、预报、研究服务。但是,根据目前人类所能掌握的科技水平,不管采取何种避雷措施,在强雷暴天气出现时,难… 相似文献
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为获取雷暴高能辐射的强度、能量及时间等信息,本文设计了一套基于双通道闪烁体探测器的分布式雷暴高能辐射观测系统.该系统由远程终端单元和高能辐射探测单元组成,基于本底放射性统计涨落实现了短爆发事件的在线识别,并可通过累积能谱数据离线检索γ射线辉光事件,具有测量能量范围宽、抗干扰能力强、易组网等特点.利用碘化钠闪烁体探测器建立的国内首个分布式雷暴高能辐射观测系统在人工引雷试验中得到应用验证,在全部5次人工触发闪电的22次先导/回击过程中,捕获到17次高能辐射事件.试验结果表明该系统具备复杂电磁环境下的雷暴高能辐射在线监测与数据采集能力,将为本领域研究持续提供观测资料,推动国内高能大气物理研究的发展. 相似文献
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下击暴流为雷暴天气中强下沉气流猛烈冲击地面后形成并沿地面传播的近地面短时强风,其风场特征同传统的大气边界层近地风显著不同。近年来下击暴流作用下输电线-塔结构的倒塌破坏事故层出不穷。根据美国、澳大利亚和南非等国的调查,80%以上的输电线-塔的风致倒塌事故主要为下击暴流所引起。而我国对此却少有研究。据此,本文简要介绍了下击暴流在输电线-塔抗风研究中的重要性,并从尺度特征、风速特征、随机特征和压力特征四个方面对下击暴流的基本特征进行了综述。其次,阐述了下击暴流对输电线-塔结构的灾害作用和下击暴流作用下输电线-塔的破坏特征。最后,论述了下击暴流对输电线-塔结构抗风设计的影响。指出了将雷暴强风,尤其是发生频度高、破坏性强的下击暴流纳入到风荷载规范,是非常重要而迫切的工作。 相似文献
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本文自主研制性能稳定的双金属球三维电场探空仪,并结合气象探空仪等构建了雷暴电场-气象综合探空系统,实现了雷暴云内三维电场及温度、湿度的同步测量.2019年夏季对华北平原地区雷暴开展穿云观测,并结合地面大气电场、雷达回波、变分多普勒雷达分析系统(VDRAS)反演的动力场等资料进行综合研究,首次给出该地区雷暴云内的电场和电荷结构分布特征.对2019年8月7日发生的一次中尺度对流系统电场探空发现,在雷暴减弱阶段,其弱回波区内存在5个极性交替的电荷区:4.4~5.6 km之间的上部正电荷区(0℃附近)、3.6~4.4 km之间的中部负电荷区和1.0~3.6 km之间的下部正电荷区,此外在1 km下方有一个负极性电荷区,雷暴云顶附近5.7~6.9 km之间为一个弱负极性屏蔽电荷区.其中,中部负电荷区和下部正电荷区由多个不同强度、不同厚度的电荷层构成.此外,电场探空系统在中部负电荷区高度范围内经历的上升—下沉—再次上升的往返探空数据表明,雷暴云内动力环境复杂,电荷结构分布相似但又有所差异,反映了实际雷暴云内电荷分布的时空不均匀性和复杂性. 相似文献
9.
中国华北春季沙尘天气频次的气候预测模型 总被引：2，自引：0，他引：2
对中国北方沙尘天气发生频次进行气候预测具有重大社会价值和科学意义,也是十分困难的一项课题．以北京站和天津站的情况为代表,首先分析了中国华北春季沙尘天气频次（DWF）的季节平均表面温度、降水、北极涛动、南极涛动、南方涛动、近地面经向风以及欧亚西风指数的相关性,旨在利用这些气候要素或大气环流因子建立中国华北春季DWF的预测模型．然后,分别基于观测资料和中国科学院大气物理研究所九层全球大气环流格点模（IAP9L—AGCM）的32a（1970～2001年）跨年度集合回报试验结果,建立了两个适合于预测中国华北春季沙尘天气发生频次的预测模型——模型Ⅰ和模型Ⅱ．其中,模型Ⅰ的试预报结果与实测间的相关系数达到0．933,因此有望提前一个季度进行较为准确的预测．如果基于气候模式的跨年度预测结果,在模型Ⅰ的预测思想上弓l入春季沙尘天气发生的同期气候信号,预测模型（模型Ⅱ）的试预报结果与实测间的相关系数可达0．948,不但表现出了更大的预测潜力,还可将模型Ⅰ实时气候预测的时间提前到半年．最后,检验了两个模型的实时气候预测能力．结果表明,这两个模型对中国华北春季DWF的年际变化和线性趋势都具有较强的预测能力,并且各具优势．其中,模型Ⅱ可在很大程度上提高IAP9L—AGCM原预测方法对春季DWF的实时预测准确度,可以考虑将其预测思想在中国其它沙尘天气多发区的气候预测中推广应用． 相似文献
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Space physics is a young discipline in Turkey. Since 1970 various national near-Earth space research activities and several
international collaborations have been conducted in Turkey and some of these are continuing. In May 2004 a four-week Graduate
Course on “Space and Atmospheric Physics I and II” was held at the Tübitak Feza Gürsey Institute in Istanbul, Turkey. This
paper explains the background behind this initiative, and gives an introduction to the topics that were covered during the
course, especially emphasizing how solar-terrestrial physics is applied to space weather. During the course the students,
in parallel with the lectures delivered, performed projects based on the curriculum, and using information available on the
Internet and in the literature. A resumé of their results concerning the well-known “space weather” event at the end of 2003
is given. 相似文献
12.
A three-component geomagnetic survey was carried out during the period from 2002 to 2004 in China including Jiujiang-Ruichang region. Comparing the ＂2005.0 surface spline model of China geomagnetic field＂ created on the basis of the survey data with the ＂1970.0 surface spline model of China geomagnetic field＂, we can see an obvious abnormity in the geomagnetic horizontal component within a range of about 100 km around the epicenter of the Ms=5.7 Jiujiang-Ruichang earthquake occurred on November 26, 2005. After the earthquake, we carded out a repeated geomagnetic survey at 21 stations in the Jiujiang-Ruichang region and created a corresponding ＂2005.0 partially revised surface spline model of China geomagnetic field＂. By comparing the above three models, analyzing the geomagnetic horizontal component at the profile in the Jiujiang-Ruichang region and quantitatively studying the geomagnetic data of every stations around the Ms=5.7 earthquake, we have obtained the geomagnetic abnormity associated with this earthquake. Then the geomagnetic abnormity and its relation with seismic activity are discussed in this paper. 相似文献
13.
In this paper, based on the previous study of practical use of seismic regime windows and seismic regime belts, the problem
of establishing a “seismic regime network” consisting of “windows” and “belts” is further posed and discussed according to
the observed fact that many “windows” and “belts” make responses to one earthquake. For the convenience of usage, the “seismic
regime network” is divided into two classes, the first class and the second one. The former can be used in tendency prediction
for long-term seismic activity in a large area, the latter used in short-term prediction in a small area. In this paper, after
briefly discussing the physical significance of “seismic regime network”, it is pointed out that this simple and easily used
method can be used to observe and extract seismic precursory information from a large area before a great earthquake, thus
it can provide a reliable basis for the analysis and judgement of seismic regime tendency in time and space. No doult, this
method is of certain practical significance.
The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,13, 161–169, 1991.
The English version of this paper is improved by Prof. Shaoxie Xu. 相似文献
14.
Chiara Turino Paola Morasca Gabriele Ferretti Davide Scafidi Daniele Spallarossa 《Journal of Seismology》2010,14(2):393-411
Reliable automatic procedure for locating earthquake in quasi-real time is strongly needed for seismic warning system, earthquake
preparedness, and producing shaking maps. The reliability of an automatic location algorithm is influenced by several factors
such as errors in picking seismic phases, network geometry, and velocity model uncertainties. The main purpose of this work
is to investigate the performances of different automatic procedures to choose the most suitable one to be applied for the
quasi-real-time earthquake locations in northwestern Italy. The reliability of two automatic-picking algorithms (one based
on the Characteristic Function (CF) analysis, CF picker, and the other one based on the Akaike’s information criterion (AIC),
AIC picker) and two location methods (“Hypoellipse” and “NonLinLoc” codes) is analysed by comparing the automatically determined
hypocentral coordinates with reference ones. Reference locations are computed by the “Hypoellipse” code considering manually
revised data and tested using quarry blasts. The comparison is made on a dataset composed by 575 seismic events for the period
2000–2007 as recorded by the Regional Seismic network of Northwestern Italy. For P phases, similar results, in terms of both
amount of detected picks and magnitude of travel time differences with respect to manual picks, are obtained applying the
AIC and the CF picker; on the contrary, for S phases, the AIC picker seems to provide a significant greater number of readings
than the CF picker. Furthermore, the “NonLinLoc” software (applied to a 3D velocity model) is proved to be more reliable than
the “Hypoellipse” code (applied to layered 1D velocity models), leading to more reliable automatic locations also when outliers
(wrong picks) are present. 相似文献
15.
赵和云 《地震学报(英文版)》1994,7(3):465-474
ＴｈｅｐａｔｔｅｒｎｃｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆｔｈｅｔｅｎｄｅｎｃｙｖａｒｉａｔｉｏｎｓｏｆｅａｒｔｈｒｅｓｉｓｔｉｖｉｔｙａｎｄｉｔｓｒｅｌａｔｉｏｎｔｏｅａｒｔｈｑｕａｋｅｓＨｅ－ＹｕｎＺＨＡＯ（赵和云）（ＥａｒｔｈｑｕａｋｅＲｅｓｅａｒ... 相似文献
16.
Hidemi M. Ito Akihiko Wakayama Mitsuyuki Hoshiba De-Yi Feng Ming-Zhou Lin 《地震学报(英文版)》1993,6(4):813-821
We have developed a workstation-assisted information processing system. The system has three major functions: information
retrieval from seismic data, detection of earthquake precursors, and graphical display of relevant results. Fuzziness is inevitably
involved in these functions, an adequate treatment of which is vital. The system accepts instructions given by a successive
choice of words in hierarchal structure, which is followed by a tune-up of the corresponding membership function. The degrees
of fuzziness in the outputs are recognized visually, for example, by coloring. This contrivance together with dynamic data
exchange among the above functions facilitates the operation of the system.
The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,15, 399–406, 1993.
This study is partly supported by a project “Fuzzy systems and their applications to human and natural sciences” of Science
and Technology Agency. 相似文献
17.
Automatic pickings in earthquake real-time monitoring systems often contain noise bursts and/or phases of different event(s)
occurring almost simultaneously. Typically, a locator uses these picks as P and S waves arrival times coming from a single
event and, therefore, should be complemented by a distinctive phase association logic. The method we propose manages to automatically
associate data related to different events and eliminates the influence of spoiled data from single events. The method is
based on “network beamforming”, a robust and stable algorithm, which utilizes a hypocenter grid search for the stack maximum
of a set of complex exponents applied to the P phase readings. The algorithm separates the residual outliers and then uses
them for location. If successful, a hypocenter is established for the interfering event. The solutions obtained are overall
robust and independent from the estimate of origin times. The preliminary epicenter for the grid search is provided by the
intersection of perpendicular bisectors in the modified “arrival order algorithm” or by the modified “Tnow” algorithm, which uses non-arrival information. We applied this method to automatic first arrival phase readings of 915 events
registered by the Hi-net Japan seismic network and our results are statistically promising. Here, we present two interesting
and complicated examples. 相似文献
18.
Introduction In the years when the reliable data could not be obtained and in the analysis of strain property and magnitude in history, the intensity, property and activity pattern of strain field were mainly inferred on the bases of geometric characters of surface traces and behaviors (especially the faults) as well as the characteristics of petrology (XIE, et al, 1993; Molnar, Tapponnier, 1975, 1977; Tapponnier, Molnar, 1977; FU, et al, 2000). However, they are the averaged results accumu… 相似文献
19.
O. K. Kedrov E. O. Kedrov N. A. Sergeyeva L. P. Zabarinskaya V. R. Gordon A. B. Chulkov 《Izvestiya Physics of the Solid Earth》2010,46(11):974-999
The Method of Dynamic Calibration (MDC) of stations of the International Monitoring System (IMS) was developed for calibrating
regions where no underground nuclear explosions were carried out, with the purpose of providing conditions for implementation
of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) in nontrivial cases. Initially, the MDC had been presented in [Kedrov,
2001; Kedrov et al., 2001; Kedrov O.K. and Kedrov E.O., 2003] and then considered in detail in [Kedrov et al., 2008]. The
core of MDC relates to adapting diagnostic parameters for the identification of underground nuclear explosions (UNE) and earthquakes
elaborated for the region of Eurasia, taken as a basic region (BR), for other researched regions that differ from BR in the
character of the attenuation of seismic waves. The unique characteristic of this method lies in the fact that calibration
of diagnostic parameters with the help of attenuation coefficients b
Δ at varied source-station traces is implemented using only natural seismicity data within the limits of an explored region
and does not require special underground chemical explosions. The MDC algorithm is implemented in the research program ”Kalibr”,
which was tested by using the experimental data from Eurasia region. It is shown in this work that MDC can be used for calibration
of regions where a very low level of natural seismicity is observed. According to the results of the calibration of diagnostic
parameters at IMS stations in several regions of North America, Africa, and Asia, the approximate classification of propagation
conditions for seismic signals at source-station traces in platform and tectonically active regions is made. The results for
the development of two research programs, “Spektr” and “Signal”, are presented; this software is intended for automation of
calculation procedures for spectral diagnostic parameters of UNEs’ and earthquakes’ identification by amplitude spectra of
P waves and by the maximal amplitudes of P, S, and LR signals. The application of these programs allowed us to accelerate the whole calibration procedure for a particular source-station
trace using the ”Kalibr” program. 相似文献
20.
IntroductionMore than 30 years has passed since gravity method was used to Study the eanhquake prediction in China in later 1960s (In America, Germany, Japan and the former Soviet Union etC. it haspassed nearly half a century). In this 30 years the most remarkable success achieved are as follows.First, in the cognition aspect, the questions whether the gravity will change or not before earthquake and how much the magnitUde of change has been answered. TO the fial queStion, the answer is p… 相似文献