Turbulence Models And Measurements Of Different Underlying Surfaces(Inland,Seaside And South Pole)

It is necessary to measure and estimate the intensity of optical turbulence because of the significant impact of the quality of ground-based astronomical observation and the characteristics of laser transmission in atmosphere.The contribution to the turbulence of the total layer from the near ground layer is different for the reason that the generation and development of atmospheric optical turbulence at different underlying surfaces is different.Therefore,it is of great practical utility to study atmospheric optical turbulence measurement and model estimation on different underlying surfaces.The article consists of two parts,including the commissioning and testing of a multi-layer atmospheric parameter measurement system for the inland astronomical site selection in Antarctica,and the measurement of three different underlying surfaces in Chengdu,Maoming and Antarctic Taishan Stations.Conventional weather parameters are modeled and statistically analyzed.The main work of this article is summarized as follows:(1)Completed the test of multi-layer turbulence and meteorological parameters measurement system in the Antarctic near ground.Through the instrumental noise test of indoor ultrasonic anemometer and temperature pulsation meter,outdoor consistency test and stratified comparison test,the results show that:the anemometer system noise equivalentCn2 is 2×10-16 m-2/3,and the temperature pulsation meter system noise equivalentCn2 does not exceed 2×10-18 m-2/3.the results measured by anemometer system is similar to the temperature pulse meter in the daytime,and the value measured at night ultrasonic anemometer is 2-10 times larger than the temperature pulse meter.(2)The results measured in Maoming,Antarctic Taishan Station and Chengdu near the ground were compared.The turbulent intensity ranges from high to low is:Maoming near the coast,Chengdu,and Antarctic Taishan Station.The Cn2 value of daytime is greater than the nighttime in Chengdu and Maoming,and the maximum value generally appears at midday.The Cn2 value at night is greater than the daytime,and the maximum generally appears in the early morning in Taishan station.The three stations all show the law of daily change.After the sunrise and around one hour before sunset,the minimum Cn2 value will appear.And the time when the minimum Cn2 appears is corresponds to the time when the temperature difference between the two layers is equal to zero.(3)On the basis of Monin-Obukhov's similarity theory,the near-surface refractive index structure constants of Chengdu,Maoming and Taishan stations in the Antarctic were estimated using atmospheric meteorological parameters(temperature,humidity,and wind velocity)at two height layers.Several statistical magnitude(mean absolute error,root-mean-square error,deviation correction root mean square,correlation coefficient)were used to statistically analyze the estimate value of the Cn2 in three stations near the ground.The results show that the correlation coefficient between the estimated value and the measured value of the three-region is 0.87,0.92,and 0.72 respectively.Therefore,it is feasible to use the meteorological parameters to estimate the model.(4)The reasons of the error between the model estimation and measurement has been analyzed.The main factors are the limited application of the Similar theory,the incomplete of parameter input,and the use of similarity functions for different underlying surfaces,especially in the condition of weak turbulence.