淮阴地区旱涝气候分析     

韩长春 《气象》1996,22(7):46-48

作者以淮阴市历年的雨涝，干旱实况为依据，参考农业，水利部门统计的受灾面积，防洪排涝能力，农作物不同生育期的需水量等因素，按季节分析雨涝，干旱灾害与雨量关系，确定年季不同级别的旱涝指标，其分析结论是４０多年来旱涝灾年发生的频数超过正常年，且涝灾多于旱灾，重于旱灾，但秋旱多于秋涝。  相似文献   

秋冬季节转换与次年汛期旱涝的关系     

王莘芳  汪克付 《气象》1996,22(12):40-42

利用日平均气温资料，将秋冬季节转换的过程划分为４种基本类型，讨论了不同类型与次年夏季（５—９月）旱涝的关系，同时应用该关系制作夏季旱涝的长期趋势预测  相似文献   

旱灾成灾综合指数的研究   总被引：1，自引：1，他引：1  

宫德吉  郝慕玲  侯琼 《气象》1996,22(10):3-7

分析了旱灾成灾的主要影响因素。指出作物的需水 状况及环境对水的供应状况是决定旱灾能否发生的关键因素。自然降水的变异、土层水的调贮量、作物不同生育期对缺雨的反应状况及人类活动都会对灾害情产生影响。  相似文献   

秋冬季节转换与次年汛期旱涝的关系     

王莘芳  汪克付 《气象》1996,22(12):40-42

利用日平均气温资料，将秋冬季节转换的过程划分为４种基本类型，讨论了不同类型与次年夏季旱涝的关系，同时应用该关系制作夏季旱涝的长期趋势预测。  相似文献   

夏季西北干旱区干,湿年环流及高原动力影响差异的对比分析   总被引：11，自引：13，他引：11  

吴统文  钱正安 《高原气象》1996,15(4):387-396

为了更深入地分析西北干旱气候形成的原因，并研究各影响因子之间的联系，利用１９７９－１９８６年夏季（６－８月）的ＥＣＭＷＦ的格点资料和我们先前划分的夏季高原北侧地区干，湿等级资料，进一步作了夏了高原北侧地区干，湿间平均环流和高原动力等因子差异的对比分析，讨论了这些差异对该地区干。湿年形成的贡献，结果指出，由于青藏高原及深居内陆环境造成了西北干旱背景。而高原的热力，动力作用，环流特征等各因子逐年之间的  相似文献   

江淮地区旱涝时期大气潜热能和大气感热能的计算与比较   总被引：2，自引：0，他引：2       下载免费PDF全文

陆渝蓉  翟盘茂 《地球物理学报》1996,39(5):608-614

旱涝灾害的发生，追究其形成的物理原因，主要是由于地球和大气系统能量传输异常而导致水、热收支与循环变异所造成．本文选取江淮流域夏季出现洪涝和干旱年份的水、热资料，计算了江淮地区整层大气柱以及从地面到１５０ｈＰａ共分１０层的逐层大气的潜热能和感热能，对其的能量含量、能量输送量及能量源、汇（辐合、辐散量）作了时空分布特征的分析比较，探讨了旱涝形成的物理原因．  相似文献   

DROUGHT DISASTERS AND ENVIRONMENTAL CHANGE DURING PAST 30 YEARS IN AFRICA     

《地理学报(英文版)》1996,(1)

AfricaisadevelopingcontinentwherequiteafeWcoUnnesarepoliticallyunstable,economicallydifficultor/andhavehadsenousdisasters,especlallydroughdisasters.ThedroughdisastersinAfricahavehadfarmoreseriousresults,farlargeraffededareasthan0thercontinatsdunngpastafeWdecades.Thedeatht0llbecauseOfthemwasstrildng.Inffospaperthebasicsituationandtheresultsofdroughsanddroughdisasters,therootcausesOfthedisastersandmeasuresf0rcontrollingthemareconsideredandanalysedfromthevieWPolntofenvironmentalchmp.klltheseas…  相似文献   

广东省水稻旱灾的评价及防旱抗旱对策   总被引：9，自引：0，他引：9  

宋丽莉  张昌昭 《热带地理》1996,16(3):196-203

根据广东省水稻旱灾实况，提出了水稻旱情和干旱灾情没的评价指标，分析了广东省解放后历年旱，晚稻旱情和灾情及分布和变化规律，并针对本省的自然条件和灌溉现状提出了防旱抗旱措施。  相似文献   

The Role of Mid-Latitude Pacific Cyclones in the Winter Precipitation of California*     

Marilyn Raphael  Gerald Mills 《The Professional geographer》1996,48(3):251-262

The characteristics of the mid-latitude Pacific cyclones that produce precipitation over California are investigated statistically to determine their role in governing precipitation receipt. From all cyclones occurring over the Pacific Ocean from December through March and between 1965–1990 inclusive, we identify a subset of cyclones likely to produce precipitation over California. The characteristics analyzed are track, frequency, duration, speed, central pressure, and proximity. These are related to monthly precipitation for the entire period and are also used to explain the difference in precipitation received during the earlier (wet) and latter (dry) halves of the 1980s. Results indicate that the winter cyclones responsible for precipitation over California originate in the southeast quadrant of the region influenced by the Aleutian Low and decay south of the Gulf of Alaska. The extent of cyclonic activity over the east Pacific Ocean near California diminished during the dry period. There were fewer cyclones, they were significantly weaker, and they traveled along a more meridional track during the dry period.  相似文献   

Deformational history of the Precambrian Kolar Schist Belt,South India: Constraints for the tectonic evolution     

Dilip K. Mukhopadhyay 《Journal of Earth System Science》1990,99(2):201-213

In the Kolar Schist Belt well-preserved small-scale diastrophic structures suggest four phases of folding (F₁ — F₄). The near coaxial F₁ andF ₂folds are both isoclinal with long-drawn out limbs and sharp hinges. The axial planes of bothF ₁andF ₂folds are subvertical with N-S strikes; these control the linear outcrop pattern of the Schist belt. The later folds (F ₃and F₄) are important in small-to-intermediate scales only and are accommodation structures formed during the relaxation period of the early folding episodes. Mesoscopic shear zones, post-F₂ but pre-F₃ in age, are present in all the rock types in this area. The F₁ and F₂ folds and the mesoscopic shear zones were formed during a continuous E-W subhorizontal compression. Available geochemical and isotopic data show that the Kolar Schist Belt with ensimatic setting is bounded by two granitic terrains of contrasting evolutionary histories. This, together with E-W subhorizontal compression over a protracted period of time, strengthens the recent suggestions that the Kolar Schist Belt represents a suture. This belt then marks the site of a continent-continent collision event of late Archaean-early Proterozoic age.  相似文献