Adelaide地区大气重力波的气辉观测

Observations of Atmospheric Gravity Waves in Airglow Over Adelaide

利用澳大利亚Adelaide(34.5°S,138.5°E)地区7年(1995—2001年)的OH和OI气辉观测数据,以及同地区中频雷达所测背景风场数据,通过最大熵谱分析方法,统计分析了该地区大尺度重力波的传播特性.结果表明,(1)在中层顶气辉观测区,利用OH气辉探测到48个重力波事件,利用OI气辉探测到29个重力波事件,这些重力波的周期和水平相速度分别集中在68min和36m/s左右,具有东南向的优势传播方向,平均仰角为8°～10°,接近水平方向传播;(2)通过OH气辉和OI气辉观测到了同一个重力波事件,并根据两个高度上观测到的扰动相位差判断该重力波为上行波.

This paper presents the statistical results of the propagation characteristics of largescale gravity waves observed by OH and OI airglow during the years from 1995 to 2001 in Adelaide, Australia （34.5°S, 138.5°E）. The propagation parameters were obtained through the three-channel maximum entropy method. Totally 48 gravity wave events were identified by the OH airglow observation and 29 events were identified by OI. The periods and horizontal phase speeds of these gravity waves peak at about 68 min and 36 m/s, and the gravity waves shows an obvious dominating direction of propagating south-eastward. The mean elevation is 8°- 10°, which shows the nearly horizontal propagation trends. It was also found that an up-going gravity wave event was observed nearly simultaneously by OH and OI. However, in most cases, the gravity waves cannot be observed simultaneously by OH and OI observations, because of the errors of the instruments or the effects of strong wind shears on gravity waves in the mesopause region.