Fine structure of the low-latitude mesospheric turbulence
Fine structure of the low-latitude mesospheric turbulence
复制标题
低纬度中层湍流的精细结构
DOI：
--
复制
发表时间：
2009
期刊：
影响因子：
--
通讯作者：
S. Das
中科院分区：
文献类型：
--
作者：
U. Das;H. Sinha;S. Sharma;H. Chandra;S. Das
[1]从斯里哈里科塔（13.7°N，80.2°E）进行了火箭载电子密度测量，以研究低纬度中层中性湍流的精细结构。利用连续小波变换（CWT）得到了电子密度起伏谱，并估算了湍流参数。目前的研究表明，湍流并不是连续存在于中间层，而是存在于不同厚度的层中，厚度从100米到3公里不等，其间散布着稳定区域。最重要的结果如下：（1）低纬地区100-200 m厚的湍流薄层的识别。发现这些薄层位于湍流厚层的边缘。(2)首次从实验观测中检测到边缘区域湍流参数的急剧梯度。这在早期的模拟研究中只看到过。(3)卫星观测到的温度表明重力波活动增强，并建议在低层大气中的大陆陆块的深对流是这些重力波的主要来源，负责产生湍流。
[1] Rocket-borne measurements of electron density were conducted from Sriharikota (13.7°N, 80.2°E) to study the fine structure of low-latitude mesospheric neutral turbulence. Spectra of electron density fluctuations were obtained using the continuous wavelet transform (CWT), and the turbulence parameters were estimated. The present study shows that turbulence is not present continuously in the mesosphere but exists in layers of different thicknesses varying from 100 m to 3 km, interspersed by regions of stability. The most important results are the following: (1) Identification of thin layers of turbulence with 100–200 m of thickness over low latitudes. These thin layers are found to lie on the edges of the thick layers of turbulence. (2) Sharp gradients in turbulence parameters at the edge regions are detected from experimental observations for the first time. This was seen earlier in simulation studies only. (3) Satellite-observed temperatures show enhanced gravity wave activity, and it is suggested that deep convections over the continental landmass in the lower atmosphere are the major source of these gravity waves responsible for generation of turbulence.