卫星遥感技术是研究大气气溶胶时空变化规律的重要手段之一。高分四号卫星(GF-4)作为新一代静止卫星,不仅具备更多的可见-近红外波段,而且具有超高 时空分辨率的特点,可以执行对固定区域连续观测或凝视扫描覆盖观测,为气溶胶光学厚度定量反演提供了有利条件。基于GF-4静止卫星超高时 空分辨率卫星数据,在深入了解卫星观测模式及传感器波段对气溶胶反演敏感性基础上,基于地气时变差异核心思路,开发了针对GF-4超高时空分辨 率数据气溶胶光学厚度反演算法;设计并实现了具备业务化反演气溶胶光学厚度能力的软件系统,软件系统具备多线程、全自动运行能力, 满足卫星数据处理业务化需求。利用该系统对GF-4数据进行了处理和分析,通过地基仪器实测的气溶胶光学厚度进行了验证, 取得了初步结果。结果表明,该系统具有良好的可靠性和稳定性,可以服务于大气颗粒物时空变化遥感监测。

Satellite remote sensing is a useful and important tool to monitor the aerosol temporal and spatial changes. GF-4 satellite is a new generation geostationary satellite which has more spectral bands in visible to near infrared spectrum and high spatio-temporal resolution. GF-4 grabs images in focusing and scanning observation modes. So GF-4 characteristics create a good condition for aerosol monitoring. Utilizing the ultra-high spatio-temporal resolution satellite data acquired by GF-4, an operational software system was designed to retrieve aerosol optical depth. The characteristics of GF-4 observation modes and the sensibility of sensor bands to aerosol retrieval were investigated. The retrieval algorithm of aerosol optical depth was developed for ultra-high spatio-temporal resolution satellite data of GF-4, with a core idea of time-varying difference of reflectance between surface and atmosphere. Then, an operational software system was developed. The software system has the capabilities of multithreading calculation and automatic operation, which meet the demands of satellite data operational processing. A series of GF-4 satellite data were processed and validated by the ground-based experimental data, which can be got from the ground-based aerosol observation network. Preliminary results were obtained and indicate that the system has good reliability and stability. This remote sensing software system can be useful to monitor spatio-temporal changes of atmospheric particulates.