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1.
本文以甘孜州2009年“7.23”特大泥石流灾害为例,应用常规气象资料对灾害的气象成因及其灾害的诱发因素进行了分析。表明:短时强降水是引发这次特大泥石流灾害的直接原因。其地貌、地表及土壤结构状况本身以及大量地兴修水利,挖掘沙土,破坏生态平衡成为这次特大泥石流灾害发生的诱发因素。根据地质气象灾害的成因分析对防灾减灾提出具体的防御对策。  相似文献   

2.
云南楚雄特大滑坡泥石流气象成因   总被引:3,自引:1,他引:2  
余峙丹  张辉  郭荣芬 《气象科技》2010,38(1):136-140
2008年11月2日连续性的大雨、暴雨引发了云南楚雄州特大地质灾害,造成巨大生命财产损失。文章利用高空探测资料、测站雨量、加密自动站雨量、卫星云图等资料分析了诱发楚雄州"11.02"特大滑坡泥石流灾害的气象成因。结果表明:除了地质地貌自然原因外,楚雄州出现历史罕见秋季连续强降水天气过程是造成这次灾害的前期气候背景;中尺度辐合天气系统、充沛水汽输送及辐合、高低空急流、中低层切变导致的11月1日20:00至2日20:00楚雄州暴雨是引发"11.02"滑坡泥石流灾害的直接气象原因。  相似文献   

3.
利用加密地面自动气象站、常规MICAPS资料、每6 h一次的1°×1°NCEP再分析资料、FY-2E气象卫星云图、多普勒天气雷达回波等多源实测资料,综合分析了2012年6月10日凌晨发生在贵州省凯里市舟溪镇的泥石流灾害的气象成因。结果表明:造成这次泥石流灾害的气象触发因素是一场短时特大暴雨所致;此次局地暴雨天气过程是在高空西南气流、近地层切变线及地面辐合线的共同作用下发生的。FY气象卫星资料揭示出中β尺度对流云团是特大暴雨发生的直接影响系统,并与泥石流灾害点的位置有密切关系。多普勒天气雷达资料分析得到此次舟溪暴雨属于暖云性质的降水,并且先后受到4个雷暴单体的影响,造成了类似"列车效应"的强降水。来自孟加拉湾的暖湿空气是本次暴雨的主要水汽来源,泥石流灾害点发生在最强上升气流的东侧,大气层结不稳定是产生强对流天气的重要前提条件。  相似文献   

4.
舟曲“8.8”特大山洪泥石流灾害气象成因分析   总被引:18,自引:4,他引:14  
曲晓波  张涛  刘鑫华  周庆亮  张小雯 《气象》2010,36(10):102-105
本文利用气象监测数据分析了2010年8月8日凌晨发生在甘肃省舟曲县的特大山洪泥石流灾害的气象成因。经过分析表明,造成此次特大山洪泥石流的主要气象触发因素是一场局地性强、短时强度大、突发性强的短历时强降雨型的强对流天气过程;经过雷达、卫星资料分析,其天气系统具有明显的中尺度特征;这种中尺度天气系统的发生、发展是在高空有冷空气东移南下的大尺度环流背景下,由低层切变线天气系统强迫作用造成的。  相似文献   

5.
"5.12"汶川特大地震重灾区泥石流滑坡气候特征分析   总被引:5,自引:0,他引:5  
本文通过对汶川“5.12”特大地震重灾区1991-2003年的泥石流、滑坡等山地灾害的终初日、时空分布及其与降水的关系的分析,还对这次特大地震造成堰塞湖的滑坡面积进行了统计分析。得出了汶川特大地震重灾区的泥石流、滑坡的时空分布、多发时段与集中发生时段、终初日及其出现地点、泥石流、滑坡与当日雨量与前期降水的关系等特征方面新的认识。指出了“5.12”特大地震造成堰塞湖的滑坡面易发生群发性泥石流、滑坡等山地灾害的严重隐患。从而为抗震救灾和灾后重建工作提供科学依据。  相似文献   

6.
2003年6月21日,维他克河发生了特大山洪,洪峰流量排在有正式水文资料记载以来的第二位,部分河沟发生泥石流,给流域造成了严重灾害。本文根据流域实测降水、流量及气象卫星云图等资料,对此次洪水、泥石流过程的水文特性和气象成因作了初步分析。  相似文献   

7.
地质气象灾害的定点预报   总被引:1,自引:0,他引:1  
本文针对地质灾害中与气象因素结合最为紧密的滑坡和泥石流两种灾害类型,从灾害成因、预报依据、预报方法、系统建设等方面阐述了定点地质气象灾害的预警与预报的理论框架,对于气象部门与国土部门联合开展地质气象灾害预警预报做出了科学的解释。  相似文献   

8.
本文针对地质灾害中与气象因素结合最为紧密的滑坡和泥石流两种灾害类型,从灾害成因、预报依据、预报方法、系统建设等方面阐述了定点地质气象灾害的预警与预报的理论框架,对于气象部门与国土部门联合开展地质气象灾害预警预报做出了科学的解释.  相似文献   

9.
该文根据气象、水文、地质灾害、灾害损失等资料,采用对比分析方法对2011年6月6日发生在黔西南州望谟县的特大暴雨山洪地质灾害影响进行初步评估。结果表明:这是一次重大的自然灾害事件,给人民群众的生命财产造成了重大损失。造成打易镇及其附近滑坡泥石流灾害的1 h雨量阈值为35 mm左右、2 h累计雨量阈值为140 mm左右。望谟河上游的打易雨量站开始出现强降水的时间与望谟河中段(望谟水文站——县城)水位暴涨、超警戒水位的时间差为2 h左右。造成这次重大灾害的原因是综合性的,首要原因是短历时突发性特大暴雨,降雨时间短、强度大,引发了特大山洪、山体滑坡、泥石流等次生灾害;其次是地理及人为因素。  相似文献   

10.
山洪泥石流是辽东半岛山区常见的一种自然灾害。由辽宁省气象台主持的“辽东半岛山洪泥石流规律及预测研究”历时7年,取得了显著的成果。 研究人员通过查阅大量资料和多次深入到灾区现场调查,分析了辽东半岛山洪泥石流产生的自然环境条件和决定泥石流发生的特强暴雨的诱发因素,揭示了山洪泥石流的成因,摸清了辽东半岛山洪泥石流灾害的规律。根据暴雨  相似文献   

11.
叶茵  余清 《贵州气象》2004,28(4):37-38
我局从1999~2003年,测报工作连续4年未出现错情,在此期间共有1个250个班,9个百班无错通过上级业务部门验收.在仪器保管、使用、维护上符合要求,对外报送的各种表、簿都能做好出门合格.  相似文献   

12.
13.
The impact of high resolution modern vegetation cover on the West African climate is examined using the International Centre for Theoretical Physics Regional Climate Model implementing the NCAR Community Land Model. Two high resolution 25 km long-term simulations driven by the output from a coarser 50-km resolution simulation are performed for the period 1998–2010. One high resolution simulation uses an earlier and coarser-resolution version of plant functional type distribution and leaf area index, while the other uses a more recent, higher-quality, and finer-resolution version of the data. The results indicate that the new land cover distribution substantially alters the distribution of temperature with warming in Central Nigeria, northern Gulf of Guinea and part of the Sahel due to the replacement of C4 grass with corn; and cooling along the coastlines of the Gulf of Guinea and in Central Africa due to the replacement of C4 grass with tropical broadleaf evergreen trees. Changes in latent heat flux appear to be largely responsible for these temperature changes with a net decrease (increase) in regions of warming (cooling). The improved land cover distribution also results in a wetter monsoon season. The presence of corn tends to favor larger precipitation amounts via more intense events, while the presence of tropical broadleaf evergreen trees tends to favor the occurrence of both more intense and more frequent events. The wetter conditions appear to be sustained via (1) an enhanced soil moisture feedback; and (2) elevated moisture transport due to increased low-level convergence in regions south of 10N where the most substantial land cover differences are present. Overall the changes induced by the improved vegetation cover improve, to some extent, the performance of the high resolution regional climate model in simulating the main West African summer monsoon features.  相似文献   

14.
由中国历史气候记录对季风导致唐朝灭亡说的质疑   总被引:1,自引:0,他引:1  
2007年1月4日杂志发表了Yancheva等10人的题为"Influence of the intertropical convergence zone on the East-Asian monsoon"(热带辐合带对东亚季风的影响)的论文[1],这是德国波兹坦地学研究中心气候动力与沉积学科的主管豪格(G.H.Haug)率领的科研小组的一项成果,认为是季风的变化引起的长期干旱导致了唐朝的灭亡.  相似文献   

15.
16.
Summary ?Some features of the climate system that can be considered predictors of the onset and end of the convective season over the Amazon were identified using one-month lag correlations and field composites. The fields analyzed were sea surface temperature (SST), outgoing long-wave radiation (OLR), vertical velocity and upper tropospheric winds. Warm (cold) anomalies in the SST in the tropical North Atlantic and the Caribbean Sea tend to be associated with delayed (early) onsets. Likewise, there is a tendency towards a delayed (early) end of the convective season with cold (warm) anomalies in these ocean regions. In addition, the SST in the cold tongue region of the equatorial Pacific is negatively, though weakly correlated with the onset date. The signal of this SST is more evident in the case of the end date, which is earlier with respect to its mean date in most of El Ni?o cases. The convective activity intensity itself conditions the onset and the end of the convective season, as it is evidenced by the behavior of the OLR and the vertical velocity fields. The more (less) intense the convective activity over South America during the preceding month, the earlier the onset and the later the end of the convective season on the Amazon region. The prediction of the onset and end dates of the convective season in the Amazon region was explored using a simple multiple regression technique based on the variables that have shown precursor signals with respect to these dates. The correlation coefficient between the predicted and the observed onset date is 0.81, and in the case of the end date, it is 0.76. The skill to predict early, delayed and normal categories was high, since in more than two thirds of the cases the category was successfully predicted, and there were no predictions of categories opposed to those observed. Received July 23, 2001; revised February 22, 2002; accepted April 26, 2002  相似文献   

17.
2005 is the bicentenary of the Beaufort Scale and its wind-speed codes: the marine version in 1805 and the land version later. In the 1920s when anemometers had come into general use, the Beaufort Scale was quantified by a formula based on experiment. In the early 1970s two tornado wind-speed scales were proposed: (1) an International T-Scale based on the Beaufort Scale; and (2) Fujita's damage scale developed for North America. The International Beaufort Scale and the T-Scale share a common root in having an integral theoretical relationship with an established scientific basis, whereas Fujita's Scale introduces criteria that make its intensities non-integral with Beaufort. Forces on the T-Scale, where T stands for Tornado force, span the range 0 to 10 which is highly useful world wide. The shorter range of Fujita's Scale (0 to 5) is acceptable for American use but less convenient elsewhere. To illustrate the simplicity of the decimal T-Scale, mean hurricane wind speed of Beaufort 12 is T2 on the T-Scale but F1.121 on the F-Scale; while a tornado wind speed of T9 (= B26) becomes F4.761. However, the three wind scales can be uni-fied by either making F-Scale numbers exactly half the magnitude of T-Scale numbers [i.e. F′half = T / 2 = (B / 4) − 4] or by doubling the numbers of this revised version to give integral equivalence with the T-Scale. The result is a decimal formula F′double = T = (B / 2) − 4 named the TF-Scale where TF stands for Tornado Force. This harmonious 10-digit scale has all the criteria needed for world-wide practical effectiveness.  相似文献   

18.
准两年振荡对大气中微量气体分布的影响   总被引:11,自引:5,他引:6  
张弘  陈月娟  吴北婴 《大气科学》2000,24(1):103-110
NCAR的包含化学、辐射、动力相互作用的两维模式(SOCRATES)移植回国后进行了初步的模拟试验,用以研究某些对环境问题重要的微量气体的化学、辐射、动力传输过程。在不考虑极地平流层云和气溶胶表面非均相化学等情况下,模式积分多年,计算结果稳定,模拟的风场、温度场显示出正常的季节变化,模拟的微量气体分布与卫星实测资料对照,结果也比较一致。为了探讨热带平流层风场的准两年周期振荡(QBO)对平流层微量气体分布的影响,我们做了QBO强迫的数值试验,即在模式中加入QBO强迫,并与不考虑QBO强迫的模拟结果对比。结果表明,QBO与其相关的次级环流所引起动力输送的变化,使平流层微量气体分布发生变化。  相似文献   

19.
Here, we analyze the characteristics and the formation mechanisms of low-level jets(LLJs) in the middle reaches of the Yangtze River during the 2010 mei-yu season using Wuhan station radiosonde data and the fifth generation of the European Centre for Medium-Range Weather Forecasts(ERA5) reanalysis dataset. Our results show that the vertical structure of LLJs is characterized by a predominance of boundary layer jets(BLJs) concentrated at heights of 900–1200 m.The BLJs occur most frequently at 230...  相似文献   

20.
流场配置及地形对西南低涡形成的动力作用   总被引:10,自引:8,他引:10  
高守亭 《大气科学》1987,11(3):263-271
本文采用定常二层模式讨论较小地形及高、低层流场配置对西南低涡形成的动力作用。指出了西南低涡的形成是与盆地、河谷以及其上气流分层有关的一种定常态.在上、下为西风分层时期,低层的浅薄暖湿西风有利于西南低涡的形成.在上、下为东、西风分层时期,上层浅薄东风亦有利于西南低涡的形成.小型的凸起山脉对西南低涡的形成没有作用.  相似文献   

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