Large-Scale Turbulence Structures in the Atmospheric Boundary Layer Observed above the Suburbs of Kyoto City, Japan
Large-Scale Turbulence Structures in the Atmospheric Boundary Layer Observed above the Suburbs of Kyoto City, Japan
复制标题
DOI：
10.1007/s10546-022-00707-8
复制
发表时间：
2022-05
影响因子：
4.3
通讯作者：
Mitsuaki Horiguchi;K. Tatsumi;A. Poulidis;Toshiya Yoshida;T. Takemi
中科院分区：
文献类型：
--
作者：
Mitsuaki Horiguchi;K. Tatsumi;A. Poulidis;Toshiya Yoshida;T. Takemi
研究了日本京都郊区上空大气边界层大尺度湍流结构的特征和发生条件。一个广泛的观测装置，包括安装在塔上的声波风速计，温度计，多普勒激光雷达和无线电探空仪，被用来检查湍流结构和垂直剖面的ABL顺风从城市。在近中性的情况下，大尺度湍流结构的时间尺度为100 - 300秒的检测在近地层中测得的流向速度分量的时间序列中的小波分析。转向不稳定的条件被认为是有利于大规模的湍流结构的出现。这些结构的存在与大气边界层的发展和白天湍流形势的变化有关。平均而言，在这个网站上，风速在较低的ABL增加在下午。从密集的观测，我们可以推断，通过湍流混合和其他机制的向下转移的动量在上层向地面延伸的高速层。在几十分钟的时间间隔内，风速会间歇性地进一步增加，在这些高风速期间，湍流结构被清晰地识别出来。
The characteristics and occurrence conditions of large-scale turbulence structures in the atmospheric boundary layer (ABL) are investigated above the suburbs of Kyoto City, Japan. An extensive observational set-up, including sonic anemometers–thermometers mounted on a tower, Doppler lidar, and radiosondes, was used to examine the turbulence structures and vertical profiles of the ABL downwind from the city. In near-neutral situations, large-scale turbulence structures with temporal scales of 100‒300 s are detected by the wavelet analysis in the time series of the streamwise velocity component measured in the surface layer. A shift towards unstable conditions is found to be favourable for the emergence of large-scale turbulence structures. Furthermore, the existence of these structures is seen to be related to the development of the ABL and the change of the turbulence situation in the daytime. On average at this site, wind speed in the lower ABL increases in the afternoon. From the intensive observations, we can infer that the downward transfer of momentum via turbulent mixing and other mechanisms extends a high-speed layer at the upper levels towards the surface. Intermittent occurrence of the further increase of wind speed in an interval of several tens of minutes is also found. Turbulence structures are clearly identified in these periods of higher wind speed.