平流层全球重力波活动的气象电离层及气候卫星观测

Global Gravity Waves in Stratosphere by Constellation Observation System for Meteorology Ionosphere and Climate Occultation Observations

利用从2007年1月~2013年2月的COSMIC(constellation observation system for meteorology ionosphere and climate)温度数据,分析了平流层(20~35 km)的全球重力波活动及其随纬度、高度和季节的变化特征,揭示了平流层不同纬度重力波活动的中期变化规律;以及重力波振荡周期随纬度的变化。赤道地区重力波全年活动很强,且存在明显的准两年振荡(quasi-biennial oscillation,QBO)。在20°S^20°N的重力波势能极大值区与强对流区域保持一致。中高纬地区重力波主要表现为冬季强夏季弱。中纬地区,两个半球冬季陆地上重力波活动强于海洋,且南美洲南部安第斯山每年除夏季外,都有较明显的重力波活动。高纬地区,南半球冬季重力波分布保持稳定,而北半球则在某些区域增强,某些区域较弱,这一现象可能是与SSW(stratospheric sudden warming)相关。通过LS谱图分析,发现QBO主要出现在平流层低纬地区,AO(annual oscillation)和SAO(semiannual oscillation)则主要出现在平流层中高纬地区。

The global morphologies of potential energy density E p from stratospheric gravity waves(GWs)are revealed by temperature profiles of COSMIC satellite from January 2007 to February 2013.The connection between Gws and latitudes,altitudes and seasons was discussed mainly,which indicate the medium-term variability of GWs in different latitudes.In the equatorial region,the activities of GWs are very strong all throughout the year and show clear QBO structure.The large gravity wave E p values found in tropics between-20°and 20°could be mainly consistent with strong convective regions.In the mid-and high-latitudes,the GWs are strong in winter and weak in summer.In the mid-latitudes,the activities of GWs on continent are stronger than that on the sea in both hemispheres.Meanwhile,the activities of GW in Andes are relatively obvious except summer.In the high-latitudes,the distribution of GW remains stable in southern hemisphere,but in the northern hemisphere,some regions enhance and another weaken.This phenomenon may be related to SSW.By Lomb-scargle spectra analysis to GW perturbation,we found that QBO mainly in low latitude and AO and SAO in the mid-and high-latitude regions.