...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of the Atmospheric Sciences >Velocity and Temperature Structure Functions in the Upper Troposphere and Lower Stratosphere from High-Resolution Aircraft Measurements
【24h】

Velocity and Temperature Structure Functions in the Upper Troposphere and Lower Stratosphere from High-Resolution Aircraft Measurements

机译：通过高分辨率飞机测量对流层上层和对流层下层的速度和温度结构函数

获取原文
获取原文并翻译 | 示例
   

获取外文期刊封面封底 >>

       
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

High-resolution measurements obtained from NOAA "best" atmospheric turbulence (BAT) probes mounted on an EGRETT high-altitude research aircraft were used to characterize turbulence in the upper troposphere and lower stratosphere at scales from 2 m to 20 km, focusing on three-dimensional behavior in the sub-kilometer-scale range. Data were analyzed for 129 separate level flight segments representing 41 h of flight time and 12 600 km of wind-relative flight distances. The majority of flights occurred near the tropopause layer of the winter subtropical jet stream in the Southern Hemisphere. Second-order structure functions for velocity and temperature were analyzed for the separate level-flight segments, individually and in various ensembles. A 3D scaling range was observed at scales less than about 100 m, with power-law exponents for the structure functions of the velocity component in the flight direction varying mostly between 0.4 and 0.75 for the separate flight segments, but close to (2)/(3) for the ensemble-averaged curves for all levels and for various sub-ensembles. Structure functions in the 3D scaling range were decoupled from those at scales greater than 10 km, with the large-scale structure functions showing less variation than those at smaller scales. Weakly anisotropic behavior was observed in the 3D range, with structure parameters for the lateral and vertical velocities on the same order as those in the flight direction but deviating from the expected isotropic value. Anisotropy was correlated with turbulence intensity, with greater anisotropy associated with weaker turbulence.
机译：从安装在EGRETT高空研究飞机上的NOAA“最佳”大气湍流（BAT）探头获得的高分辨率测量结果用于表征对流层上层和平流层下层在2 m至20 km范围内的湍流，重点是三个子公里尺度范围内的尺寸行为。针对代表41小时的飞行时间和12600 km的相对飞行距离的129个单独的水平航段进行了数据分析。大多数飞行发生在南半球冬季亚热带急流的对流层顶附近。对速度和温度的二阶结构函数进行了分析，分别针对单独的水平飞行段和各个集合。在小于约100 m的比例尺上观察到3D比例尺范围，在飞行方向上速度分量的结构函数的幂律指数在单独的航段中主要在0.4到0.75之间变化，但接近（2）/ （3）用于所有级别和各个子集合的集合平均曲线。 3D缩放范围内的结构函数与大于10 km的尺度上的结构函数解耦，大型结构函数所显示的变化小于较小尺度下的结构函数。在3D范围内观察到微弱的各向异性行为，其横向和垂直速度的结构参数与飞行方向上的顺序相同，但偏离了预期的各向同性值。各向异性与湍流强度相关，各向异性越大，湍流越弱。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号