云遮挡对海上红外透过率影响分析

Influence of Clouds Cover on Transmission of Infrared Radiation in Actual Marine Atmosphere

大气透过率是影响红外辐射传输的重要因素。由于基于海上实际气象参数的有关云对红外波段大气透过特性影响的研究还相对薄弱,因此海上红外透过率的计算不可避免地存在计算误差。构建了我国海上区域实际大气参数廓线,以海洋为下垫面,嵌入成熟、通用的大气辐射传输模型,还原真实大气环境中云遮挡对红外辐射传输的影响。研究发现,海上大气温度、湿度等参数随时空变化较大,直接影响大气透过率计算结果;以区域实际大气环境参数作输入,海洋为下垫面,计算发现云底高和云厚的变化对海上大气透过率具有明显影响,影响程度与云参数以及探测器和云层的几何位置关系密切相关。研究结果表明尽可能还原真实大气环境是研究云对海上红外辐射传输影响的基础,大气环境对计算结果造成的误差不容忽视。

Atmospheric transmittance is an important factor affecting infrared radiation transmission.The calculation of atmospheric transmittance of infrared band based on the actual meteorological parameters of marine atmospheric is still weak,which inevitably causes the calculation error.In the paper,the actual atmospheric parameter profile in coastal areas of China is constructed and embedded into MODTRAN to restore the influence of clouds cover on infrared radiation transmission in real atmospheric environment.It is found that the change of the atmospheric temperature,humidity and other parameters directly affects the calculation results of atmospheric transmittance,and the change of cloud thickness has also obvious influence on atmospheric transmittance,and its influence degree is closely related to the cloud parameters and the relative geometric position between detector and cloud layer.It is shown that to restore the real atmospheric environment as much as possible is the basis of studying infrared radiation transmission,and the error of calculation results caused by atmospheric environment cannot be ignored.