青藏高原出射长波辐射特征分析  

An Analysis of Outgoing Longwave Radiation Characteristics for Tibetan Plateau

作　　者：苏文颖[1] 毛节泰[1] 纪飞[1] 

机构地区：[1]北京大学地球物理系暴雨监测与预报国家重点实验室,北京100871

出　　处：《大气科学》2000年第3期313-323,共11页Chinese Journal of Atmospheric Sciences

基　　金：国家攀登B项目!"青藏高原地 -气系统物理过程及对全球气候和中国灾害性天气影响的观测和理论研究"资助

摘　　要：对青藏高原地区 1月、4月、7月和 1 0月高时空分辨率的出射长波辐射 (OLR)时间序列进行了谱分析。将各点的功率谱分为三类 :第一类代表日变化 (周期≤ 1d) ,另外两类分别为天气过程 ( 2d≤周期≤ 1 0d)和低频 (周期 >1 0d)变化 ;将高原分为 6个区域 ,对区域平均的各季节OLR时间序列进行功率谱分析和显著性检验 ,结果表明 :1、4、1 0月份高原上以日变化为主 ;而 7月份日变化、天气尺度变化和低频变化的贡献相当。显著性分析表明高原上最为显著的周期为 1d周期 ,2～4d的天气尺度振荡也较明显。 6～ 8d和 1 0～ 1 3d处虽有明显的谱峰 ,但只有少数地区和个别季节其谱值能超过 95%的信度检验。Spectral analysis was applied to outgoing longwave radiation (OLR) series of January, April, July and October for the Tibetan Plateau. The temporal and spatial resolutions of the OLR series were 1 hour and 12 km respectively. The spectral density was divided into three categories: the first was for diurnal variation (period≤1 day); the other two were for synoptic (2 day≤period≤10 day) and low frequency (period>10 day) variation. Then the Tibetan Plateau was divided into six areas and spectral analysis and significant test were carried out for area averaged OLR series. The results show that in January, April and October diurnal variation was dominant and in July diurnal variation, synoptic variation and low frequency variation had about the same values over the Tibetan Plateau. The most significant period was 1 day and 2～4 day period was also significant. Although there were obvious peaks over 6～8 day and 10～13 day period, only a few areas and seasons could pass the 95% degree of confidence.

关 键 词：出射长波辐射 谱分析 青藏高原 显著性检验 

分 类 号：P422.6[天文地球—大气科学及气象学]