中文摘要：

本文利用中纬站点Miramar Nas（32.87°N,117.15°W）的探空数据提取了对流层和低平流层的惯性重力波参数并计算了动量通量-相速度谱.分析表明低层大气重力波动量通量谱很好地满足高斯分布.高斯拟合的参数分析显示：（1）冬季西风急流对向东传播的波的吸收使得对流层向西传播的波的高斯峰值明显强于向东传播的波;（2）重力波在由对流层向平流层的传播过程中谱展会增大,这可能是波与背景相互作用以及波-波相互作用的结果;（3）急流对重力波的吸收与反射以及对流层顶附近波的耗散使得低平流层总动量通量远小于对流层的.受背景风场影响,谱的季节变化呈现出一定规律.多普勒效应对谱产生了两方面的影响,一方面背景风较大时多普勒效应会使谱展宽,另一方面多普勒效应会显著改变谱的中心本征相速度,使得动量通量谱在同一方向上呈现不对称性.

英文摘要：

Inertial gravity waves in the troposphere and the lower stratosphere（TLS） were extracted by using the data from Radiosonde observations at a mid-latitude station Miramar Nas（32.87°N,117.15°W）.The momentum flux spectra of gravity wave were calculated.Analysis shows that the momentum flux spectra in the lower atmosphere satisfy the Gaussian distribution.The investigation into Gaussian parameters indicates（1） eastward propagating waves are absorbed by the winter westerly jet and as a result the Gaussian peaks of the westward propagating waves are obviously larger than those of the eastward propagating waves,（2） wave-mean flow interaction and wave-wave interaction are likely to lead to the increase of the spectra width during the process when waves propagate from the troposphere to the stratosphere,（3） the total momentum flux in the lower stratosphere is much smaller than the counterpart in the troposphere,probably because of the absorption and reflection by jet as well as the wave dissipation near the tropopause.Affected by the background wind,the momentum flux spectra exhibit distinctive seasonal variations.Doppler effect profoundly influences the spectra from two aspects.Firstly,Doppler effect will widen the width of the spectra when the background wind is strong.Secondly,Doppler effect would significantly change the intrinsic phase speed at Gaussian center,leading to asymmetric spectra.