Experimental investigation of open sea atmospheric optical turbulence

Abstract

In this article, a high-quality fiber optical turbulence sensing array is arranged on the ocean-going instrumentation ship-Yuan Wang for 37 day continuous measurement. It is the first time that the spatial multipoint simultaneous measurement of maritime atmospheric optical turbulence has been realized. According to the measurement, the essential characteristics and quantitative data of the atmospheric optical turbulence on the open sea are obtained. Then the Greenwood spatial correlation function model is used for evaluating the outer scale of optical turbulence by a nonlinear fitting algorithm. Finally, the optical turbulence spectrum is divided into two sections, and the power spectrum scaling exponent is given by a section algorithm. Results show that the intensity of maritime atmospheric optical turbulence is a little smaller than that in the near ground layer and has no obvious diurnal variation characteristic. The value of outer scale is small and in a range of 0.2-0.3 m. It is easily found that the probability that the turbulence spectrum scaling exponent conforms to -5/3 is about 25% near the surface of open sea, which is smaller than that in the near ground layer.