The El-Nino-triggered landslides and their socioeconomic impact on Kenya   总被引：1，自引：0，他引：1  

W. M. Ngecu  E. M. Mathu 《Environmental Geology》1999,38(4):277-284

 Kenya experienced extraordinarily heavy rainfall between May 1997 and February 1998 due to the El-Nino weather phenomenon. This period of about 10 months heavy rainfall caused widespread landslides and floods which were experienced in various parts of the country. Normally mid-December to late March is the driest and hottest season in Kenya. However, during this period, the season turned out to be the wettest with one of the heaviest precipitation events recorded in the country in the past several decades. Research investigations have revealed that the landslides were a result of four major factors. The factors included, geology and soils of the landslide prone areas, high relief, steep slopes with poor anchorage for slope stability, continuous heavy precipitation which resulted into oversaturation of rocks and soils. The effects of the El-Nino-triggered landslides in Kenya were enormous. Although statistical data about landslide destruction are not presently quantified, human and animal fatalities and plant destruction were enormous. Fertile farmlands, roads, railway lines, bridges, telephone and power lines were relocated and destroyed. Soil erosion which increased from higher surface runoff and surface exposure filled rivers with sediments. The sediments were transported to the hydro-electricity producing dams which eventually became clogged and power generation stopped. The national economic loss to the country is estimated at about US $ 1 billion and will take a long time to recover. Received: 7 April 1998 · Accepted: 2 March 1999  相似文献   

El Nino年和La Nina年的非线性临界层与副高的形成、维持和振荡     

陶丽  陆维松 《热带气象学报》1999,15(1):1-9

采用欧洲中心１９８２年１２月、１９８３年４月、１９８４年１０月和１９８５年４月的月平均纬向风场实际观测资料,作为非线性临界层模式的基本气流进行数值积分,得到：用１９８２年１２月和１９８３年４月的基流模拟出的副高强、范围大、数目少,维持２￣３个单体,且向西移,东西振荡周期１－２个月。用１９８４年１０月和１９８５年４月的基流模拟出的副高弱、范围小,成带状分布,数目多达４个单体,副高合并、分裂得较快,亦  相似文献   

广州气温与厄尔尼诺的多尺度相互联系   总被引：3，自引：0，他引：3  

吴洪宝  特&#;米&#;松涅奇金 《热带气象学报》1999,15(4):340-346

通过对广州气温距平和Ｎｉｎｏ　３、Ｎｉｎｏ　１＋２区ＳＳＴＡ序列做小波变换,研究了广州气温变化与ＥＮＳＯ振荡过程之间的多尺度联系,发现它们都存在着强的十年际振荡。年际尺度的振荡为正相关,十年际风度为负相关。由于ＳＳＴＡ的十年际变率是由强厄尔尼诺事件的韵律产生的,因此;广州气温对强烈厄尔尼诺的响应性质上不同于对普通厄尔尼诺的响应．  相似文献   

东亚冬季风年际变化的ENSO信息 I.模拟资料分析     

穆明权  李崇银 《气候与环境研究》1999,(2)

系统分析了观测海温强迫９层大气环流模式的模拟资料,结果表明该大气环流模式能够对与ＥｌＮｉｎｏ、ＬａＮｉｎａ事件爆发有关的赤道太平洋异常纬向风和对流活动有很好的模拟;模拟中的东亚冬季风具有明显的年际变化特征,这种变化与观测结果有很好的一致性,而且进一步分析发现这种年际变化具有显著的２～７年的周期,即东亚冬季风异常与ＥＮＳＯ密切相关。  相似文献   

舟山冬季暴雨的特征   总被引：1，自引：0，他引：1  

王雷 《海洋预报》2004,21(3):70-75

文章分析了冬季暴雨发生时的环流形势和物理量场分布特征,揭示了冬季暴雨的发生与厄尔尼诺现象有着一定的相关。同时,分析了单站要素的变化,为以后的冬季暴雨预报提供参考。  相似文献   

Movements of the Western Pacific Warm Pool Centroid and Their Relationship to Sea Surface Temperature Changes in Ni(n)o Regions     

FANG Mingqiang Ocean Remote Sensing Institute  Ocean University of China  Qingdao  P.R.China 《中国海洋大学学报(英文版)》2005,4(2)

By using monthly historical sea surface temperature (SST) data for the years from 1950 to 2000, the Western Pacific Warm Pool (WPWP) climatology and anomalies are studied in this paper. The analysis of WPWP centroid (WPWPC) movement anomalies and the Nino-3 region SST anomalies( SSTA) seems to reveal a close, linear relation between the zonal WPWPC and Nino-3 region SSTA, which suggests that a 9' anomaly of the zonal displacement from the climatological position of the WPWPC corresponds to about a 1 ℃ anomaly in the Nino-3 region area-mean SST. This study connects the WPWPC zonal displacement with the Nino-3 SSTA, and it may be helpful in better understanding the fact that the WPWP eastward extension is conducive to the Nino-3 region SST increase during an El Nino-Southern Oscillation (ENSO) event.  相似文献   

THE FREQUENCY CHARACTERISTICS OF WARM AND COLD EPISODES IN THE NI(N)O REGIONS   总被引：3，自引：0，他引：3  

孙卫国  程炳岩  黄海仁 《热带气象学报(英文版)》2005,11(2):200-205

On the basis of NOAA/CPC data of sea surface temperature anomaly in the Nino regions during Jan. 1950 - Dec. 2003, the wavelet power spectrum of SST were studied with significance and confidence testing at different scales in this paper. It shows that the SST are provided with multi-time scales structure nested one another, and vary on scales of 2 - 7 years, 8 - 20 years and ＞30 years. The most significant variation of the warm and cold episodes is in the 4-year band of period. The power, frequency structure and confidence of the same episode are different in different Nino regions. The intensity of oscillations is increasing at low frequency bands and decreasing at high frequency bands from east to west in the Nino regions, especially after 1970.  相似文献   

近百年ElNino/LaNina事件与北京气候相关性分析   总被引：8，自引：0，他引：8       下载免费PDF全文

刘桂莲  张明庆 《气象》2001,27(2):3-6

通过对近百年El Nino/La Nina事件与北京气候相关性研究发现，El Nino/La Nina事件与北京夏季（6－8月）降水、平均最高气温（7月）和冬季（1月）平均最低气温之间相互关系显著。El Nino事件与夏季降水、冬季平均最低气温呈负相关，与夏季平均最高气温呈正相关，造成降水减少，气温年较差较大，大陆性增强的气候特点。La Nina事件与夏季降水、冬季平均最低气温呈正相关，与夏季平均最高气温呈负关，使降水增加，气温年较差减小，大陆性减弱的气候特点。  相似文献   

中国华北旱涝与印度夏季风降水的遥相关分析   总被引：17，自引：0，他引：17  

郭其蕴 《地理学报》1992,47(5):394-402

本文根据1871—1986年共116年印度夏季风期（6—9月）雨量与中国华北东部旱涝级别资料研究了两个地区旱涝关系的变化。发现在1921—1950年关系减弱,而1891-1920和1951—1980年关系均较密切。利用相应时期北半球海平面气压图及赤道东太平洋海温资料,讨论了两个地区旱涝关系形成机制和变化原因。  相似文献   

1987年El Nino后期（9—11月）西太平洋大气静力能的收支     

马柱国  姚兰昌 《高原气象》1992,11(1):66-72

本文利用中科院1987年西太平洋考察资料和中央气象局出版的太平洋、大西洋资料反演出了一套利用温度和高度求算湿度的方法。通过该方法并利用美国国家气象中心的KWBC(5°N×5°S网格点资料)的温度和高度资料,计算了1987年厄尔尼诺期间9—11月西太平洋海域(0—30°N,120—170°E)大气静力能量的变化及其与周围的交换。结果表明,在这个时期,该区域上空大气是强的能源区,区域向周围输出能量。  相似文献