摘要
运用去趋势涨落分析方法分别研究NCEP/NCAR再分析资料中的高度场和温度场,揭示了东亚区域高度场和温度场的标度指数分布特征.结果表明高度场和温度场都具有长程相关性,且二者空间分布特征总体匹配.对同一层格点资料而言,低纬度地区标度指数较大,长程相关性较好;中高纬度地区标度指数较小,长程相关性较差,呈现比较明显的纬向分布特征.不同层格点资料的标度指数分布有所区别,具体表现为高度场资料随层数的增加,其平均标度指数值呈增长趋势且纬向分布特征更为明显;在高度场中下层青藏高原地区标度指数明显大于同纬度其他区域.温度场资料随层数的增加平均标度指数先减小再增大,也具有一定的纬向分布特征.总体而言,高度场长程相关性的标度指数值要高于温度场.分季节研究表明,高度场和温度场也具有较好的长程相关性,冬季标度指数高于其他季节,为利用冬季信息制作夏季汛期预报提供了一定的理论依据.
The paper investigates the height and temperature fields reanalysis data of NCEP/NCAR by means of detrended fluctuation analysis method,and gives their scaling exponent distribution of East Asia region.The empirical investigation indicates that both of height field and temperature filed have the property of long range correlation,which matches with the features of space distribution as a whole.As for the grid data of the same layer, the long range correlation varies obviously when the latitude changes.The lowlatitude areas near the equator have a bigger scaling exponent and a better long range correlation,whereas the mid-latitude and high latitude areas have a smaller scaling exponent and a worse long range correlation.The average scaling exponent increases with the layer growth of height field data,and the scaling exponent varies obviously when the latitude changes.The scaling exponent of QinghaiTibet Plateau is obviously greater than other areas at the same latitude.For the data of temperature,the average scaling exponent first decreases with the layer growth then increases,and the average scaling exponent has a definite latitude trait.All in all,the scaling exponent of height field＇s long range correlation is greater than that of temperature field.The investigation for different seasons displays that the long range correlation exists in height field and temperature field as well.And we find that the scaling exponent of winter time is greater than that of other seasons.This may provide a theory for the summer flood season forecast which is based on the winter information.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2009年第9期6640-6650,共11页
Acta Physica Sinica
基金
国家自然科学基金(批准号:40875040)
国家科技支撑计划(批准号:2007BAC29B01和2007BAC03A01)
公益性行业(气象)科研专项(批准号:GYHY200806005)共同资助课题~~
关键词
高度场
温度场
长程相关性
去趋势涨落分析
height field, temperature field, long range correlation, detrended fluctuation analysis
