3种再分析资料的高空温度与中国探空温度资料的对比:年平均特征

Comparative analysis of free atmospheric temperature between three reanalysis datasets and radiosonde dataset in China:Annual mean characteristic

利用中国105站的探空资料以及NCEP/NCAR、ERA和JRA3种再分析资料,采用线性趋势、标准差、相关系数、EOF分析等多种统计分析方法,对再分析资料年平均的高空温度在中国区域的可信度进行了分析。研究表明:在数值上,3种再分析资料的高空温度均小于探空资料的高空温度,NCEP/NCAR资料在对流层上层更接近于探空资料,ERA和JRA资料则在对流层中下层与探空资料更为接近;在描述年际变化和长期变化趋势方面,ERA资料在我国北方的对流层上层的再现能力较好,NCEP/NCAR资料在我国南方的对流层上层的再现能力较好,而3种再分析资料在对流层中下层的再现能力相当;在时空变化特征方面,NCEP/NCAR和ERA资料能较好地表现高空温度的年代际变化特征,而ERA和JRA资料则能较好地表现年际变化特征。

Based on radiosonde dataset from 105 stations in China, NCEP/NCAR reanalysis dataset, ERA reanalysis dataset and JRA reanalysis dataset, a study is performed on the reliability of the annual mean free atmospheric temperature from reanalysis datasets in China by means of linear analysis, stand- ard deviation,correlation coefficient as well as EOF decomposition. Results suggest that：In numerical aspects,three reanalysis datasets are all lower than the observed dataset, and NCEP/NCAR dataset is much closer to the observed dataset in upper troposphere while ERA and JRA datasets are closer in mid- dle and lower troposphere;In terms of annual and interdecadal trend, ERA dataset has higher ability to reproduce those trends in the upper troposphere in north region while NCEP/NCAR dataset is better in the upper troposphere in south region;Three reanalysis datasets have comparable ability in reproducing the trend in middle and lower troposphere; In the aspect of spatial and temporal variation characteristics, NCEP/NCAR and ERA datasets can preferably perform the feature of interdecadal variance while ERA and JRA datasets can reveal the characteristic of annual variance well.