鄱阳湖区平垸行洪、退田还湖后的防洪减灾形势分析   总被引：4，自引：0，他引：4  

吴敦银李荣昉  王永文 《水文》2004,24(6):26-31

根据鄱阳湖区“退田还湖”的实际资料，采用洪水模拟的方法分析计算出“退田还湖”降低湖口站洪水位和减少1954年洪水超额分洪量，分析了“退田还湖”后鄱阳湖区的防洪减灾形势，提出应继续加强对鄱阳湖区防洪工程的建设，探讨了“退田还湖”后江湖洪水关系的变化趋势。  相似文献   

华南地区崩岗侵蚀灾害及其防治   总被引：9，自引：0，他引：9  

刘瑞华 《水文地质工程地质》2004,31(4):54-57

根据区域调查和定位研究资料,介绍了华南地区崩岗侵蚀及其灾害特点,概述了崩岗的形成、发育规律及其演变过程,分析了崩岗侵蚀及其灾害的影响因素。提出进行崩岗灾害防治时,应在水土保持传统方法基础上,整合水文地质学和工程地质学及其它相关学科理论,应用GIS技术对崩岗侵蚀进行科学监测和管理,为坡地利用和环境整治以及灾害防治提供依据。  相似文献   

Effects of temperature and humidity upon the transport of sedimentary particles by wind   总被引：3，自引：0，他引：3  

Cheryl McKenna Neuman 《Sedimentology》2004,51(1):1-17

Wind tunnel simulations of aeolian transport carried out over a range in mean temperature between 32 °C and ?9 °C suggest that cold airflows support higher mass transport rates (Q) than very warm air. The magnitude of this increase is larger than expected, so that analytical and semi‐empirical models underestimate Q. Extrapolation of the results suggests that, at ?40 °C, as for example in the dry valleys of Antarctica in winter, Q may be as much as 70% higher than for the equivalent wind speed in hot deserts at air temperatures of 40 °C. Temperature‐dependent changes in air density and turbulence contribute to this result. The decreased tension of water adsorbed onto particle surfaces at low temperatures is postulated to reduce interparticle cohesion and, thus, to increase the elasticity of particle impacts on cold beds. Definition of the roles that temperature and humidity play in aeolian transport is relevant to studies of palaeoenvironmental reconstruction and extraterrestrial (or planetary) geology. Investigation of present‐day, cold climate features and of climate change effects also requires knowledge of these fundamental relations.  相似文献   

Meteorological Office, Pune-411 005     

U. S. De  Medha Khole  M. M. Dandekar 《Natural Hazards》2004,31(2):487-497

Natural disasters like floods, tornadoes, tropicalcyclones, heat and cold wavewreak havoc and cause tremendous loss ofproperty all over the world. Most ofthe natural disasters are either dueto weather or are triggered due toweather related processes.Extreme weather events claimed thousands oflives and caused damage on vastscale. Recent super cyclone which affectedOrissa in 1999, Bangladesh cyclone of1970 and Hurricane Andrew in 1992 areexamples of some of the more damagingtropical cyclones which affected developingas well as the developed world. Heatand cold waves are also extreme events,which cause enormous losses in terms oflives lost and human discomfort and ailmentsarising out of them. The heat waveof 1995 and 1998 are still fresh in the mindof the Indian public. The estimated lossof human lives due to heat wave in 1998 was morethan 15,000. Economic losses asa result of these disasters and in particular inassociation with tropical cyclones haveincreased enormously over the last three decades.During 1961–1991, total loss oflives from drought alone was 1,333,728 overthe whole world. In terms of economiclosses, there is 8–10 fold increase from thebase figure of 1960. The socio-economicimpact of natural disaster is complex dependingupon the vulnerability of the placeand mitigation strategies that are put in place.Meteorology plays a crucial role in forewarningpeople about the severe/extremeweather systems and a constant endeavour by themeteorological services worldover has gone a long way towards minimizing thelosses caused by natural disasters.The paper summarises the natural disasterstatistics over south Asia and the possibleprediction strategies for combating theirsocio-economic impacts.  相似文献   

利用遥感综合分析西风引导气流与地形对沙尘运移路径的影响   总被引：2，自引：7，他引：2  

刘志丽  马建文  张仁健  王志刚  哈斯巴干  李启青 《中国沙漠》2004,24(3):330-334

沙尘暴的发生受大气环流、地表状况、降雨的影响，还受到局部地区地形的影响。一次规模较大的沙尘暴过程，沙尘可以从蒙古国和我国西部沙源地输送到我国东部、韩国、日本乃至夏威夷、美国西海岸。中日亚洲沙尘暴ADEC项目对亚洲沙尘暴的起沙、传输和降落的运行机制已经作了深入的研究，并建立了亚洲沙尘暴的数值模拟系统。本文以影响北京地区的沙尘暴事件为例，利用遥感技术，综合DEM地形数据和地面实测数据分析西风引导气流和地形对沙尘运移路径影响，将MODIs影像数据和DEM地形数据以及地面观测站点实测数据相结合，进行综合分析，结果表明在一次沙尘暴过程中，沙尘在运移过程中的运移路径明显地受到西风引导气流、沙尘粒子自然沉降规律以及局部地形的影响，要预防(减少)北京地区的沙尘暴仅仅作好北京地区的生态环境建设是不够的，加强北京周边地区，尤其是张家口地区、官厅水库库区及库区周围地区的生态环境建设尤为重要。  相似文献   

中国热带近百年气候波动与灾害     

黄镇国  张伟强  HUANG Zhenguo  ZHANG Weiqiang 《地理学报(英文版)》2004,14(Z1)

The temperature appeared rising trend during the 20th century in China's tropics.Two cooling stages and two warming stages in the process of climatic fluctuation can be recognized.After the 1980s the climate is the warmest which corresponds to the global change,but the warmest period is the 1940s in Kunming.The climate pattern mostly appears contemporaneity of warming and humidity,which is different from the situation of whole China.The natural disasters tend to be aggravated.The number of typhoons increased.Flood damages occurred frequently in the years of more typhoons.The number of droughts and cold damages increased.It was snowed in Guangzhou.There was frost in Haikou and Yaxian.Four years of heavy snow have been recorded in Kunming.  相似文献   

2003年9月19日陕西暴雨分析          下载免费PDF全文

高菊霞  李建芳 《山西气象》2005,(2):5-8

利用太原地区发生的798个地质灾害个例和汛期降水资料,从地质环境背景着手,在地理信息系统(MAPGIS)支持下,对太原地质灾害危险性区划和诱发因素进行了系统研究。提出了精细的地质环境概率量化评价方法,得出了地质灾害影响因素的重要结论。建立了地质灾害预报模型,制定了预报等级标准和预报规则。经业务试验,预报结果与实况基本吻合。  相似文献   

自动风向转换程序设计思路          下载免费PDF全文

李鸿飞  程波范  郝惠平  姜子明  武志跃  刘小伟 《山西气象》2005,(2):43-46

由于OSSMO 2004版地面测报业务软件中抄录报表风向不太方便，故长治县气象局自行设计了自动风向角度和方位的转换程序。本程序用OBJECT PASCAL语言编写，在DELPHI中实现，采用Microsoft．Jet．OLEDB．4．0数据库引擎及ADO的方式操作数据库。  相似文献   

Numerical Simulation of Wind and Temperature Fields over Beijing Area in Summer   总被引：4，自引：0，他引：4  

HU Xiaoming  LIU Shuhu  WANG Yingchun  LI Ju 《Acta Meteorologica Sinica》2005,19(1):120-127

1. IntroductionThe basic role of urban-rural boundary layer re-search is to study all kinds of physical process changesin the atmosphere boundary layer over urban and itssurrounding areas. Urban heat island (UHI) is a well-known feature of urban-rural climate. Attempts toincrease the understanding of the causes of the UHIand other urban-rural boundary layer phenomena haveused observational, theoretical and modelling methodssince long before. Seaman (1989) used a hydrostaticmodel, with real …  相似文献   

2003年2月14日新疆石河子南5.0和5.4级地震灾害减轻因素的分析     

罗福忠  胡伟华  宋立军 《内陆地震》2005,19(1):86-89

2003年2月14日新疆石河子南发生了5．0和5．4级地震。地震发生在北天山石场东南高山区内，位于亚马特断裂与斜切天山的博罗科努断裂所夹持断块的南缘。地震仅对石河子南山矿区所属的红沟煤矿、小沟煤矿与沙湾县煤矿等50、60年代建造的部分危房造成了轻微的破坏，大部分地区的房屋基本完好。造成地震灾害减轻的主要原因为多条断裂的隔震作用与居民点位于山区较平缓地带、场地条件较好等因素。  相似文献