基于非制冷红外焦平面阵列的全天空红外测云系统

Whole sky infrared cloud measuring system based on the uncooled infrared focal plane array

云的地面观测是对本地天气进行实时监测的重要工作。目前,主要采用人工目测方法进行云的地面观测,无法准确提供夜间云的资料。为了实现云的全天空昼夜自动监测,采用非制冷红外焦平面阵列(UIRFPA)和扫描的方式,通过拼图、定标、大气修正、云识别等数据处理,研制成功了全天空红外测云系统。该系统由光学测量单元、扫描单元、环境参数测量单元、采集与控制单元和数据处理单元组成。初步的观测试验表明,该系统所给出的全天空云分布图像以及云量、云族与实际天空状况一致,考虑探测器工作温度效应的非制冷红外焦平面阵列定标模型,可满足全天空云监测的辐射定量测量要求,定标处理以及云识别算法可行。

Ground observation of cloud is a primary part of real time monitoring local weather. Visual observation is at present a basic method of ground observation of cloud, but it cannot correctly provide cloud data at night and monitor cloud continuously. Based on the uncooled infrared focal plane array （UIRFPA） and scanning method,the whole sky infrared cloud measuring system （WSICMS） was developed for automatically and continuously monitoring whole sky cloud day and night.The WSICMS was comprised of the optical measuring unit, scanning unit, environment parameter measuring unit, collecting and controlling unit, and data processing unit. The whole sky cloud distribution and cloud cover were obtained after building-up of image, calibrating, atmospheric correcting, and cloud detection. Preliminary experiments indicate that the cloud distribution given by the WSICMS can reflect the natural cloud distribution. The calibration model of the UIRFPA in which the working temperature effect is taken into account can meet the need of the quantitative measurement of radiation for monitoring the whole sky cloud. The results prove that the calibration algorithm and cloud detection algorithm are practical. The WSICMS is a promising equipment for providing quantitative cloud data which would be useful for cloud climate analysis and numerical weather model.