近50年来中国西北地区尘暴发生及其可能的动力机制  

Dust storm occurrence and its possible dynamic mechanism in northwestern China over the past 50 years

作　　者：金彦香[1] 李昊[1] 李丰山[1] 刘英英[1] 李渊[1] 

机构地区：[1]兰州大学西部环境教育部重点实验室,兰州730000

出　　处：《兰州大学学报（自然科学版）》2015年第5期633-638,共6页Journal of Lanzhou University(Natural Sciences)

基　　金：中央高校基本科研业务费专项资金项目(LZUJBKY-2014-259;LZUJBKY-2014-261);高等学校博士学科点专项科研基金项目(20130211110035)

摘　　要：结合美国国家环境预报中心及国家大气研究中心再分析气候资料,通过考察1960-2007年中国西北地区137个站点春季累计尘暴发生频次与研究区和西伯利亚地区的温度、气压、风速等气候因子之间的相关关系,初步揭示了西北地区春季尘暴发生的演化趋势及其潜在动力机制.研究表明,1960-2007年中国西北地区尘暴频次总体呈减少趋势;西伯利亚和西北地区上一年冬季和当年春季均温与尘暴频次均呈显著负相关;西伯利亚和西北地区冬春季温差、气压差与尘暴频次均呈正相关.初步研究表明,近20年来,西伯利亚和西北地区温度的升高以及西伯利亚地区较高的增温幅度导致尘暴发生区平均风速的减小,是尘暴频次减少的主要动力原因.In combination with the monthly mean reanalysis data from the national environmental protection committee/national center for atmospheric research（NCEP/NCAR）,we analyzed the changes in dust storm frequencies for spring season in northwest China from 1960 to 2007.The correlations between cumulative dust storm frequencies and climatic factors,i.e.,temperature,air pressure,wind speed over Siberia and northwestern China were analyzed.The results suggest that from 1960 to 2007 the dust storm frequency in northwestern China displayed a decreasing trend.And negative correlations existed between dust storm frequencies and the mean preceding winter temperature of the Siberian region and spring temperature of northwestern China as well.Differences in temperature and air pressure between the Siberian region and northwestern China were positively correlated with dust storm frequencies over northwestern China.Over the past 20 years,increase in temperature over the Siberian region and northwestern China,especially the warming-up weather in the Siberian region,might have played an important role in the decreasing dust storm frequencies.The increase in air temperature cloud strongly affected the pressure gradient between the Siberian region and northwestern China,which in turn reduced wind speeds and then diminished the dust storm frequencies.

关 键 词：尘暴 大气温度 大气压 风速 西北地区 西伯利亚地区 

分 类 号：P425.55[天文地球—大气科学及气象学]