A new algorithm for high temporal and spatial resolution aerosol retrieval using gaofen-4 and landsat-8 data
37th Annual IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2017, 2017-07-23 to 2017-07-28.
High temporal and spactial resolution aerosol retrieval is a difficult task because of the absence of corresponding satellite data. Due to the lack of a shortwave infrared band near 2.1 um aboard on Gaofen-4 instrument, which is critical for determining surface reflectance. In this paper, a new algorithm resolving the problem based on Gaofen-4 that was placed in Geosynchronous (GEO) orbit and Landsat-8 data was proposed. Also, Gaofen-4 sensor band mean solar irradiance (BMSI) was calculated which was not open to public until now. In the algorithm, normalized difference vegetation index (NDVI) was used to identify dark target pixels that have certain linear relationship over blue and red bands'surface reflectance. In order to remove Gaofen-4's geometric deformation, the data were processed with RPC Landsat-8 panchromatic data. The algorithm was applied to two cities, Beijing and Chengdu. The result, aerosol optical thickness (AOT) with a 50m ×50m resolution, indicated the algorithm can be effective for vegetation area or low surface reflectance area. The algorithm is very useful and significant for environmental protection, air quality monitoring and atmospheric pollutants sources tracing.