中国北方春季沙尘暴频次的多要素线性拟合  

Linear Fitting of Multi-Meteorological Factors of Spring Dust Storm Frequency for Northern China

作　　者：李万源[1,2,3,4] 吕世华[1] 董治宝[2] 王式功[3] 田文寿[3] 余晔[1] 沈志宝[1] 陈玉春[1] 郭勇涛[3] 

机构地区：[1]中国科学院寒区旱区环境与工程研究所寒旱区陆面过程与气候变化重点实验室,甘肃兰州730000 [2]中国科学院寒区旱区环境与工程研究所沙漠与沙漠化重点实验室,甘肃兰州730000 [3]兰州大学半干旱气候变化教育部重点实验室,甘肃兰州730000 [4]中国气象局干旱气候变化与减灾重点开放实验室,甘肃兰州730000

出　　处：《高原气象》2010年第5期1302-1313,共12页Plateau Meteorology

基　　金：中国气象局兰州干旱气象研究所干旱气象科学研究基金项目(IAM201015);半干旱气候变化教育部重点实验室开放基金(兰州大学中央高校基本科研业务费专项资金)(223-860011)共同资助

摘　　要：利用1953-2005年地面风速及地温(5 cm和40 cm深处)等18个气象要素的春季标准化资料对我国北方97个测站的标准化春季沙尘暴频次进行了线性拟合,结果表明:无论对单要素拟合还是对多要素拟合,要素与沙尘暴频次间的(平均)相关程度决定着其对后者的拟合效果,相关程度越高,拟合效果越好。若与实际级别相同的拟合沙尘暴频次视为准确,则全区约有33%的测站,其拟合准确率≥50%;53年间约有39.6%的年份,其拟合的准确范围≥50%;对所有年份和所有测站而言,约45.6%的沙尘暴频次能够被准确地拟合,拟合的沙尘暴频次略低于实际频次。根据线性拟合方程中各要素前的系数可断定,18个要素中风速和蒸发量是沙尘暴的正影响因子,而水汽压、相对湿度和最低气温等则是沙尘暴的负影响因子,其他一些因子对沙尘暴的影响方式具有明显的区域性差异。Utilizing the normalized data of 18 averaged or accumulated meteorological factors in each spring during 1953-2005,including wind speed,ground temperature（at 5 cm and 40 cm deeps）,temperature（including the daily maximum and minimum temperatures）,relative humidity,vapor pressure,precipitation（including the daily maximum precipitation and the precipitation continuing for a longest period）,numbers of rainy day（including number of rainy days continuing for a longest period）,numbers of dry day continuing for a longest period,evaporation,sunshine duration,total and low cloud clusters,the normalized spring dust storm frequencies at 97 observation stations distributed over North and Northwest China have been fitted linearly and empirically,finally showing that,generally,the absolute correlation coefficients between the dust storm frequency and the factors can determine the fitting accuracy.Provided that a fitted frequency lying on the same level as the real one can be regarded as accurate,33% of the 97 observation stations have a fitting accuracy rate ≥50%,and 39.6% of the years 1953-2005 have an area with fitting accuracy ≥50%.For all the stations and years,about 45.6% of the fitted frequencies lie on the same levels as the real,i.e.,about 45.6% of the fitted frequencies are accurate in some sense.The fitted dust storm frequency is generally a little smaller than the real.It can be believed that,wind speed and evaporation are generally positively affecting dust storms in Northern China,but vapor pressure,relative humidity,the minimum temperature affect them negatively.Other affecting dust storms is positively in some places but negatively in other places.

关 键 词：中国北方 春季沙尘暴频次 气象要素 线性拟合 

分 类 号：P445.4[天文地球—大气科学及气象学]