Proceedings Article | 29 September 2017
KEYWORDS: Satellites, Climate change, Radiometry, Environmental sensing, Climatology, Atmospheric modeling, Earth observing sensors, Sensors, Systems modeling, Atmospheric optics
The Global Change Observation Mission (GCOM) aims to establish and demonstrate a global, long-term satelliteobserving
system to measure essential geophysical parameters to facilitate understanding the global water circulation and
climate change, and eventually contribute to improving future climate projection through a collaborative framework with
climate model institutions. GCOM consists of two polar orbiting satellite observing systems, GCOM-W (Water) and
GCOM-C (Climate). The first satellite, GCOM-W with Advance Microwave Radiometer -2 (AMSR-2), was already
launched in 2012 and has been observing continuously. The follower satellite, GCOM-C with Second Generation Global
Imager (SGLI), will be launched in Japanese fiscal year 2017. SGLI enables a new generation of operational moderate
resolution-imaging capabilities following the legacy of the GLI on ADEOS-II (Advanced Earth Observing Satellite-II)
satellite. The SGLI empowers surface and atmospheric measurements related to the carbon cycle and radiation budget,
with two radiometers of Visible and Near Infrared Radiometer (VNR) and Infrared Scanning Radiometer (IRS) which
perform a wide-band (380nm-12μm) optical observation not only with as wide as 1150-1400km FOV (field of view) but
also with as high as 250-500m resolution. Also, polarization and along-track slant view observation are quite
characteristic of SGLI, providing the sensor data records for more than 28 standard products and 23 research products
including clouds, aerosols, ocean color, vegetation, snow and ice, and other applications. Sensor instrument proto-flight
tests including optical characterization tests such as radiometric and geometric were completed, and satellite system
proto-flight tests have finished including thermal vacuum, vibration and acoustic test. In this paper, the pre-launch phase
instrument characterization of SGLI flight model and status of GCOM-C satellite system flight model along with the
overview of them will be described. Especially we focus on the pre-launch geometric and radiometric performance test
results, in-orbit calibration activities and methodologies: VNR's on-board calibrator, IRS's on-board calibrator and
calibration maneuver, and in-orbit verification plan during a commissioning phase lasting approximately 3 months.
