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题名 河西地区干湿变化特征分析及干旱年预测
姓名 赵慧
院系 大气科学学院
专业 大气物理学与大气环境
学位名称 理学硕士
外文题名 Analysis of Dry/Wet Variation Characteristics and Prediction for Years of Drought in Hexi Region
第一导师姓名 张文煜
关键词 再分析资料;适用性;干湿特征;影响因子;预测模型
外文关键词 reanalysis data;applicability;dry/wet characteristic;influencing factors;prediction model
学科 理学
摘要 我国是干旱灾害频繁发生的国家,主要分布在我国北方的干旱半干旱地区,占将近一半的国土面积,是生态系统和水资源系统最脆弱的地区。深居内陆的河西地区,是干旱半干旱区中生存环境最敏感的地区,也是我国主要的粮仓基地。在全球变暖的大背景下,河西地区是如何响应气候变化的?再分析资料在该地区的适用性如何?该地区干湿变化有何特征?河西未来干旱发展趋势如何?这些问题都值得深入研究。论文对比分析了1951-2012年CRU资料、NCEP再分析资料在表征河西地区地表特征参量方面的差异性,选取适用性更高的CRU月平均降水和月平均潜在蒸发量资料,结合计算的地表湿润指数H、标准化降水蒸散指数SPEI分析了1901-2012年河西地区地表干湿变化特征;从大气环流和海洋涛动因子角度分析了河西干旱的可能成因,通过相关分析探讨了河西干旱与降水量、气温的关系;利用基于灰色残差的BP神经网络BP-n-GM(1,1) 模型对河西地区发生干旱的年份进行了预测。
外文摘要 Drought occurs the most often in China.The arid/semiarid region mainly distributed in northern China,is the most fragile ecosystem and water resources system.Hexi region,which situated the inland,is the most sensitive region with living environment,and also the most important granary.With global warming,Hexi region would have use which way to respond the changes?Whether or not the renalysis datasets apply to Hexi region? What is the Dry/Wet Variation Characteristics in Hexi region?How about the secular variation of droughts in Hexi region?All of these definitely worth exploring.By comparing the differences between CRU data and observational data、NCEP reanalysis data and observational data in reflecting surface dry/wet characteristics, we chose a higher potential applicability data-CRU data, which included monthly average precipitation and monthly average evaporation, analyzed characteristics of surface dry/wet variation combined with the calculated surface humidity index-H, standardized precipitation evapotranspiration index-SPEI in Hexi region from 1901 to 2012. The probably genetic mechanism of Hexi drought was also discussed from atmospheric generalcirculation and interaction between ocean and atmosphere. And then we studied the influence of Hexi drought affected from precipitation and temperature by means of the corresponding period relation between them. Finally, the gray neural network prediction model, BP-n-GM (1,1) , was used for predicting years of drought occurrence in Hexi Region.
研究领域 大气探测与信息处理
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