摘要
利用1954—2005年西北五省(区)及内蒙古沙尘暴观测资料,分别对沙尘暴的年变化、日变化和持续时间频率分布进行分型和分析,初步探讨了不同类型沙尘暴时间变化特征及其成因。结果表明,沙尘暴发生日数的年变化趋势可划分为4大类型,即春季型、冬春夏型、春夏型和冬春型,它们分别占总数的29.7%、29.7%、27.1%和13.5%,除冬春型冬季沙尘暴发生最多外,其他类型均为春季最多;沙尘暴日变化可划分为3种类型,各型高发时段和峰值时间均有明显差异;持续时间分布规律也划分为3种类型,短时型、中间型和持续型。上述类型划分及分析结果表明,沙尘暴的时间变化特征也存在明显的地域差异,这一差异是某一时期内强风、沙尘源和不稳定层结三者在不同地区配置情况差异的综合反映。
The classification and regional division of temporal variation of dust storms in the middle and west of northern China have been studied by using the observation data （including the occurrence days and beginning and duration of dust storms） from 235 meteorological observation stations during 19542005.Based on the classified results of annual patterns,diurnal variation and duration patterns,the regional characteristics of temporal variation patterns of dust storms and their causes are analyzed.The main results are as follows：the annual variations of the number of dust storm days can be divided into four types,namely spring type,winter-spring-summer type,spring-summer type and winter-spring type,and they respectively account for 29.7%,29.7%,27.1% and 13.5% of the total number of stations where dust storms happened.The dust storms of three types of them （except winter-spring type） most frequently occur in spring.The diurnal variations of dust storms can be divided into three types according to the frequency distribution of the occurrence time,and there are obvious differences in the occurrence time of the peak among different types of diurnal distributions.According to the temporal statistical characteristics of dust storm duration,the duration patterns can be divided into three types：short-time type,medium type and continuous type.These above classified results of annual patterns,diurnal variation and duration patterns indicate that there are obvious regional differences in the temporal variations of dust storms.The differences are due to the match of the time in which strong wind,dust sources and thermal instability happen in different regions.
出处
《中国沙漠》
CSCD
北大核心
2010年第2期394-399,共6页
Journal of Desert Research
基金
国家科技支撑计划重点项目(2007BAC29B03)
国家重点基础研究发展计划项目(2006CB400501)
国家自然科学基金项目(40675077)共同资助
关键词
沙尘暴日数
年变化
日变化
持续时间
地域差异
number of dust storm days
annual variation
diurnal variation
duration
regional characteristic
