Mission overview of the GF-5 satellite for atmospheric parameter monitoring

Abstract

China High-resolution Earth Observation System (CHEOS) was first proposed in 2006. The main goal of CHEOS is building a new Earth observation system with high spatial, temporal, and spectral resolution, achieving all-weather, all-day, and global coverage observation capability, thereby providing operational applications for satisfying the requirements of national economic and social development. As the first satellite mission in China specifically for air quality monitoring, GF-5 satellite was launched on May 9, 2018. GF-5 is configured with six payloads, including a VIS and SWIR (shortwave infrared) hyperspectral camera, spectral imager, greenhouse gas detector, atmospheric environment infrared detector at very high spectral resolution, differential absorption spectrometer for atmospheric trace gas, and a multiangle polarization detector.The Directional Polarimetric Camera (DPC) is the first Chinese multiangle polarized earth observation satellite sensor. DPC aims to obtain multiangle polarization radiation data of the Earth's atmosphere, which can provide information on the temporal and spatial distribution of global aerosols and clouds to satisfy the requirements of global climate change research, atmospheric environment monitoring, and high-accuracy atmospheric correction of remote sensing data. The Environmental trace gas Monitoring Instrument (EMI) payload onboard GF-5 is the first Chinese satellite-borne spectrometer with the aim to measure atmospheric pollutants from space. The Chinese EMI instrument is expected to contribute to the understanding of global air quality and atmospheric chemistry, similar to predecessor European and American satellite missions, e.g., the Ozone Monitoring Instrument (OMI) and TROPOspheric monitoring instrument (TROPOMI). Several trace gases (e.g., NO2, O3, SO2, BrO, and HCHO) and aerosol can be measured by EMI. The greenhouse Gas Monitoring Instrument (GMI) is a short-wavelength infrared (SWIR) hyperspectral-resolution spectrometer onboard the Chinese satellite GF-5 that uses a Spatial Heterodyne Spectroscopy (SHS) interferometer to acquire interferograms. The GMI was designed to measure and study the source and sink processes of carbon dioxide and methane in the troposphere, where the greenhouse effect occurs. AIUS is the first occultation spectrometer developed in China; it aims to detect the trace gases over the Antarctic. AIUS operates in a solar synchronous orbit, with a nominal height of 705 km. The instrument is a Fourier transform infrared spectrometer, and its main objective is to measure O3 and other species in the stratosphere and upper troposphere to study the ozone temporal variations over the Antarctic.