基于晴空阈值法的全天空红外图像云量计算  

Total Cloud Amount Calculation Based on Clear Sky Threshold Using Whole Sky Infrared Images

作　　者：陈磊[1] 韩燕[1] 秦方强 石鹏飞[1] 关军[1] 

机构地区：[1]西北核技术研究所,陕西西安710000

出　　处：《沙漠与绿洲气象》2015年第3期50-56,共7页Desert and Oasis Meteorology

基　　金：国家863计划军口部分(2013AA8061002)资助

摘　　要：为提高新疆戈壁地区云的自动化观测水平,基于全天空红外成像仪(WSIRCMS)获取的红外辐射图像,利用辐射传输模式SBDART分析了仪器测量波段对有云无云状况的敏感性并构建了拟合方程,同时利用典型季节的晴空辐射样本拟合了晴空曲线并统计形成了晴空阈值,最后利用统计晴空阈值对全天空红外辐射图像进行云像素识别和总云量计算。将不同季节总云量计算结果同人工观测结果对比验证表明:观测时段算法计算总云量和人工观测总云量差值在±2成以下的概率均在80%以上,说明该方法具有较高的准确度和较强的实用性,在观测业务中具有较好的应用前景。To improve the ground-based automatic observation of total cloud amount （TCA） in Xinjiang Gobi region, based on the cumulative infrared radiation images obtained by Whole Sky Infrared Cloud Measuring System （WSIRCMS）, the sensitivity of instrument measurement band to different sky conditions （including clear and cloudy） was analyzed using radiative transfer model SBDART, and the fitting equation suitable for relationship of atmospheric downward infrared radiation and zenith angle was designed, and then the clear sky threshold of typical seasons was determined by statistically analyzing the clear sky infrared radiation samples using fitting equation, and TCA was calculated using the clear sky threshold. Feasibility and accuracy of the clear sky threshold method were verified by comparing with the artificial TCA observation data and that the probability of difference within ＋2 was higher than 80%, this showed that the method has high accuracy and has a good prospect in daily TCA observations.

关 键 词：总云量 晴空阈值 红外图像 

分 类 号：S161[农业科学—农业气象学]