不同途径获得的大气重力波参数扰动场特征对比分析

重力波参数气候特征是确定全球大气模式中重力波参数化方案的一个重要环节,利用高垂直分辨率探空资料扰动场是获取重力波参数气候特征的基础数据和重要手段。目前,通常采用2～4阶曲线拟合、带通滤波方法获取高垂直分辨率探空资料扰动场,但针对不同方法之间的扰动场差异特征研究较少,本文利用2～4阶曲线拟合、带通滤波方法(0.5～5.0km)获取2014—2017年太原地区(112.55°E,37.78°N)高垂直分辨率探空资料扰动场,采用相关系数、Lomb-Scargle、不同区间范围占有率方法进行研究,结果表明:①不同方法之间的纬向风扰动场、经向风扰动场、温度扰动场均存在较明显差异,且相关性均较弱;②Lomb-Scargle分析表明,不同方法得到的平均纬向风扰动场、平均经向风扰动场、平均温度扰动场显著含有(通过90%置信检验)的垂直波长均存在明显差异;③不同方法得到的纬向风扰动场、经向风扰动场、温度扰动场显著含有的垂直波长,在不同区间范围内的占有率均存在明显差异。

Characteristic Comparison of Perturbation Fields with Different Methods for Obtaining Atmospheric Gravity Wave Parameters

Studying the climatic characteristics of gravity wave parameters constitutes an important part of the parameterization of gravity waves in the development of a global atmospheric model. The disturbance fields obtained by using the high resolution radiosonde data are the basic data and important means to obtain the climate characteristics of gravity wave parameters. At present, the 2 to 4 order curve fitting and band pass filtering methods are used to obtain the disturbance fields of high vertical resolution radiosonde data. However, there are few studies on the differences in the characteristics of disturbance fields resulted from different methods. In the paper, the disturbance fields of the high vertical resolution radiosonde data in Taiyuan (112.55°E, 37.78°N) from 2014 to 2017 are obtained by the 2 to 4 order curve fitting and bandpass filtering methods (0.5 to 5.0 km), subsequently, studied by correlation coefficient, Lomb Scargle, and different interval range occupancy methods. The results show: (1) the disturbance fields from different order curve fitting methods show different amplitudes, different trends with height, and weak correlation; (2) the Lomb Scargle analysis shows that the significant vertical wavelengths (passed the 90% confidence test) are contained in the average zonal wind disturbance fields, the average meridional wind disturbance fields and the average temperature disturbance fields from different methods, and there are significant differences; (3) the significant vertical wavelengths are contained in the zonal wind disturbance fields, meridional wind disturbance fields and temperature disturbance fields from different methods, and there are significant differences in their occupancy rate within different intervals.