地基双波段测云系统及其对比试验  

Ground-based Dual-band Cloud Observing System and Its Comparative Experiments

作　　者：胡树贞[1,2] 马舒庆[2] 陶法[2] 秦勇[2] 郭伟[2] 温显罡[2] 

机构地区：[1]成都信息工程学院,成都610225 [2]中国气象局气象探测中心,北京100081

出　　处：《应用气象学报》2012年第4期441-450,共10页Journal of Applied Meteorological Science

基　　金：中国气象局新技术推广项目"双成像云底高度测量技术和方法推广应用"(CAMTG2010Z06)

摘　　要：针对地基测云系统中云在可见光波段与红外波段中表现出的不同特性,用双站数字式云高仪所测云高进行标校,结合地面实时观测天顶红外辐射亮温及地面环境参数,分析地面到云层底大气对红外辐射亮温的影响,从中发现利用天空红外辐射亮温来遥感云底高度的可行性,研发地基双波段测云系统。该系统以对流层大气的垂直温度递减率为理论基础,建立云层底到地面的温度递减梯度参数K,根据递减梯度参数反演天顶方向的云高。该算法不依赖于探空数据,通过实时定标形式得出符合仪器所在地的云底高反演公式。通过与维萨拉激光云高仪CL31进行数据对比分析得出,地基双波段测云系统反演结果具有较高的准确性。Clouds affect the energy balance of the earth by means of absorbing and scattering radiation, and they have influences on global climate. Precipitation of clouds is the most familiar way for the earth water circulation. In the macroscopic parameters of clouds, cloud cover and cloud base height are the primary elements in the observation of clouds, where the cloud base height condition determines cloud classification and precipitation probability. However, artificial visual observation is the main method used in China at present, which are not objective and waste a mass of work force. Therefore, the research and development of an automatic measuring cloud device is extremely necessary. A ground-based cloud observing system consists of an infrared temperature measuring sensor and a double location digital ceilometer. The double location digital ceilometer calculates the cloud height of zenith by geometry method at regular time, and the infrared temperature measuring sensor acquires brightness temperature of atmospheric radiation in real time. Based on the different characteristics of visible and infrared cloud images, the height of clouds is derived and tested by the double location digital ceilometer, com bined with real-time observation of zenith single-point infrared brightness temperature and ground environmental parameters. The influence of sub cloud air from ground to clouds bottom on infrared brightness temperature is analyzed, showing the feasibility of cloud base height remote sensing by ground-based sky infrared brightness temperature. The result shows that for low and middle clouds, the sky radiation brightness temperature of ground-based observation is relatively sensitive to the variation of cloud base height, therefore it can be used to estimate cloud base height. On the basis of decreasing principle of tropospheric vertical temperature, the temperature decreasing gradient parameter K from cloud base to the ground is defined and according to the decreasing gradient parameter inverse the cloud height

关 键 词：云底高度 红外亮温 地基遥感 双站数字式云高仪 

分 类 号：P412.15[天文地球—大气科学及气象学]