Parameterization of Cn2 using data from operational weather stations

大多数人类活动发生在较低的大气层中，是一个强烈动荡的层。其中，温度和湿度在不同的尺度上有所不同。温度和湿度的变化导致空气的折射率变化：闪烁。在夏天，当温暖的道路上闪闪发光时，这是肉眼可以看到的。与闪烁导致的视觉退化类似，成像仪器(例如用于监视和侦察、天文学)和通信系统的信号(例如无线电链路)的图像质量也会降低。闪烁的强度(我们将大致称为光学湍流)可以用空气折射率的结构参数来量化。它不仅取决于湍流温度和湿度变化的强度，而且对于不同的波长也是不同的。使用或计划安装依靠电磁辐射传播的系统的人需要知道他们可能会遇到什么样的光学湍流(在规划阶段)，或者他们在操作过程中会遇到什么。因此，需要简单但稳健的方法来基于容易获得的数据(例如标准气象站数据)来确定折射率的结构参数。这种方法既可以用于推导给定位置的结构参数的气候学，也可以用于确定运行期间的实时值。

The lower atmosphere, in which most human activities take place, is a strongly turbulent layer. Among others, temperature and humidity vary on a range of scales. The temperature and humidity variations cause variations in the refractive index of air: scintillations. This is visible to the eye as the shimmering over a warm road on a summer day. Similar to the degradation of our visual perceptions by scintillations, also the image quality of imaging instruments (e.g. for monitoring and reconnaissance, astronomy) and the signals of communication systems (e.g. radio links) are degraded.The strength of scintillations (which we will loosely refer to as optical turbulence) can be quantified with the structure parameter of the refractive index of air. It not only depends on the strength of turbulent temperature and humidity variations, but it is also different for different wavelengths. People who use or plan to install systems that rely on the propagation of electromagnetic radiation need to know what kind of optical turbulence they can expect (in the planning phase), or what they encounter during operation. Therefore, there is a need for simple but robust methods to determine the structure parameter of the refractive index based on readily available data (e.g. standard weather station data). Such a method could both be used to derive the climatology of the structure parameter for a given location, and to determine the real-time value during operation.