近50年中国西北地区干湿演变的时空特征及其可能成因探讨

• Main Authors: 闫炎, 赵昕奕, 周力平
• Other Authors: 北京大学城市与环境学院,地表过程分析与模拟教育部重点实验室,北京100871
• Format: Journal/Newspaper
• Language: Chinese
• Published: 干旱区资源与环境 2010
• Subjects: 干燥度指数; 北大西洋涛动指数; 自组织映射神经网络; 正交小波分解; aridity index; North Atlantic Oscillation; SOFM; orthogonal wavelet transform; North Atlantic; North Atlantic oscillation
• Online Access: https://hdl.handle.net/20.500.11897/72530

在全球大幅度变暖的背景下,西北地区的气候变化及其响应受到越来越多的关注。为了进一步探讨其气候变化过程与机理在时间与空间上变化的差异性,选取中国西北地区（80°E～115°E,32°N～50°N）1961-2004年140个气象台站逐日降水、日照、风速、水汽压、温度等资料,根据Penman公式计算了潜在蒸散量,并根据其与降水的关系建立了干燥度指数。采用自组织特征映射神经网络的方法,根据上述多种物理量进行西北地区内部的气候区划,寻找不同的区域异常中心。在此基础上,采用正交小波分解的方法,对各异常区域中心的干燥度序列进行分析。最后对北大西洋涛动指数对我国西北地区的区域气候变化的影响进行多时间尺度的相关分析,并从大气环流异常的角度解释其影响机制。 Against the background of a significant global warming,the trend of shifting warm humid climate in northwest China is fixed.In order to further investigate the differences of the process and the mechanism of the climatic changes,special and temporal,the precipitation,water pressure,sunshine duration,wind speed and temperature from 140 observatories in Northwest China,potential evapotranspiration were calculated using the Penman-Monteith Method recommended by FAO.Aridity index was defined according to its relationship with precipitation.Using the method of Self-Organizing Feature Maps（SOFM）,we tried to make a better regional climate classification in NW China,to find out major different abnormal centers.According this,about 43 years of aridity index in 4 different abnormal regional centers in NW China were analyzed by means of orthogonal wavelet transform.The correlation analysis at several kinds of time scales,from interannual,interdecadal to climate basic state scale was used for the impact of North Atlantic Oscillation on Aridity Index in different regional centers.At last,we tried to find out the mechanism between the two at the view of general atmospheric circulation abnormality. 中文核心期刊要目总览(PKU) 中国科学引文数据库(CSCD) 中国社会科学引文索引(CSSCI) 0 4 38-44 24