Parameterization of Cn2 using data from operational weather stations

大多数人类活动发生的低层大气是一个强烈的湍流层。其中，温度和湿度在一定范围内变化。温度和湿度的变化引起空气折射率的变化：闪烁。这是可见的眼睛，因为在一个温暖的夏日道路上闪闪发光。与我们的视觉感知因闪烁而下降类似，成像仪器（例如用于监测和侦察、天文学）的图像质量和通信系统（例如无线电链路）的信号也会下降。闪烁的强度（我们姑且称之为光学湍流）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，而且对不同的波长也有所不同。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（在计划阶段）可能会遇到什么样的光湍流，或者他们在操作过程中会遇到什么样的光湍流。因此，需要一种简单而可靠的方法来根据现成的数据（例如标准气象站数据）确定折射率的结构参数。这种方法既可用于推导给定地点的结构参数气候学，也可用于确定运行时的实时值。

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.