利用数值天气预报产品预报海面光学湍流

Forecast of Optical Turbulence in Marine Surface Layer Using Numerical Weather Prediction Products

利用数值天气预报模式预报产品开展了不同季节海面光学湍流数值预报研究,发现:南北纬30°之间海域海面光学湍流强度和大气相干长度季节变化较小,南北纬30°以外高纬度海域海面光学湍流强度和大气相干长度季节变化显著,夏半球光学湍流强度相对较弱、大气相干长度相对较大,冬半球光学湍流强度相对较强、大气相干长度相对较小。全球大部分海域,10.6μm光波10 m高度光学湍流强度大于10^(-15)m^(-2/3),0.55μm光波10 m高度光学湍流强度小于10^(-15)m^(-2/3)。若沿海面10 m高度水平传播10 km,全球大部分海域,10.6μm光波大气相干长度大于60 cm,0.55μm光波大气相干长度小于6 cm。利用两个不同数值天气预报模式同期产品制作的海面光学湍流强度预报全球海域分布特征相似,但模式水平分辨率越高,预报的海面光学湍流强度的水平分布特征越清晰。

The forecasts of the optical turbulence in the marine surface layer were made in different seasons based on the products of the numerical weather prediction model. It is found that the seasonal variations of the surface optical turbulence and the atmospheric coherence length are not significant over the oceans between 30°S and 30°N, but much larger over the higher latitude oceans with weaker surface optical turbulence and larger atmospheric coherence length in the summer hemisphere but stronger surface optical turbulence and smaller atmospheric coherence length in the winter hemisphere. The surface optical turbulence strength C^2n in the 10 m height above the sea level is greater than 10^-15m^-2/3 for 10.6 #m but less than 10^-15m^-2/3 for 0.55 μm over the most parts of the oceans around the world. If the propagation path was the horizontal path 10 m above the sea level, the atmospheric coherence length is greater than 60 cm for 10.6μm but less than 6cm for 0.55 μm over the most parts of, the oceans around the world. The horizontal patterns of the forecasted surface optical turbulence strength are similar to each other based on the same time products respectively from the two different numerical weather prediction models, but the horizontal pattern of the forecasted surface optical turbulence is much sharper with the higher model horizontal resolution.