OBSERVATIONS OF SMALL SCALE WIND SHEARS IN THE MESOSPHERE
-
摘要: 十个中层大气风剖面于1988年夏季在北欧的Andφya(69°N)上空用装有铝箔的火箭测得。使用了一种新型铝箔,使其测量的高度范围覆盖103-85km,测量的高度分辨率为25m.观测的风切变剖面显示了一多层结构,一般由3-9个切变层组成,切变层厚度通常小于200m.观测到高达40-90m/s/km的强风切变,且如此大的切变存在于所测区间内不同高度上。在一个连续测量的五个风切变剖面中,有寿命至少2.5小时,相位向下运动速度为0.4m/s,以及最大切变振幅为180m/s/km的强风切变,显示了稳定和持续特性。Abstract: Ten wind profiles were measured in summer 1988 in the upper mesosphere over And ya (69°N) with foil chaff. Anew kind of foil chaff was used then, which covers the height range of 103-85 km. The height resolution of the measurement was 25 m. The measured wind shears are observed to have a multi-layered structure whih has three to nine shear layers. The thickness of these shear layers is usually less than 200m. Very large wind shears as high as 40-90 m/s/km are observed and such large shears are present at various heights in the mesosphere. The strong wind shears revealed in a series of five shear profiles have stable and persistent features with a lifetime of at least 2.5 h, an apparent downward motion of 0.4 m/s, and a maximum shear amplitude of 180 m/s/km.
-
Key words:
- Mesospheric wind shear /
- Fine structure /
- Instability
点击查看大图
计量
- 文章访问数: 1934
- HTML全文浏览量: 34
- PDF下载量: 900
- 被引次数: 0