Conceptual design of image acquisition and operation for next generation Geostationary Ocean Color Imager(GOCI-II)

Abstract

For the succession of GOCI mission, is due for completion in 2017, development of GOCI-II was started in 2012 and is scheduled to be launched in 2018. GOCI-II has two operation modes (1) LA (Local Area) which is observation for the around of the Korean Peninsula, keep the observation from GOCI, with freely selection of the observation region in FD (Full disk) area, and (2) FD which can take images of full Earth disk around it covering a circle field of ± 60° longitude and latitude centered at the spacecraft nadir, 128.2°E. The size of LA region is same with GOCI, 2,500 km ? 2,500 km, but the GSD (Ground Sampling Distance) of LA is increased from 500 m to 250 m comparing with GOCI. The duty cycle of GOCI-II is 10 for the LA and 1 for the FD per day. The number of LA observation is also increased from 8 to 10. GOCI-II is first observation of full Earth disk with a stepstare scanning at GEO (Geostationary Earth Orbit), using 2D detector. So the operation scenario of FD needs to be optimized. In order to significantly FD observation, solar zenith angle at the earth surface needs to be applied to the operation concept. In case of ocean remote sensing, it will keep the lower solar zenith angle and it will move from east to west with time according to the position of sun. However it will be affected by sun-glint in many slot images. In this study, we suggest the conceptual operation scenario of FDnd of the Korean Peninsula, keep the observation from GOCI, with freely selection of the observation region in FD (Full disk) area, and (2) FD which can take images of full Earth disk around it covering a circle field of ± 60° longitude and latitude centered at the spacecraft nadir, 128.2°E. The size of LA region is same with GOCI, 2,500 km ? 2,500 km, but the GSD (Ground Sampling Distance) of LA is increased from 500 m to 250 m comparing with GOCI. The duty cycle of GOCI-II is 10 for the LA and 1 for the FD per day. The number of LA observation is also increased from 8 to 10. GOCI-II is first observation of full Earth disk with a stepstare scanning at GEO (Geostationary Earth Orbit), using 2D detector. So the operation scenario of FD needs to be optimized. In order to significantly FD observation, solar zenith angle at the earth surface needs to be applied to the operation concept. In case of ocean remote sensing, it will keep the lower solar zenith angle and it will move from east to west with time according to the position of sun. However it will be affected by sun-glint in many slot images. In this study, we suggest the conceptual operation scenario of FD