Global Change Observation Mission

As a part of Japan's contributions to GEOSS (Global Earth Observation System of Systems), GCOM will be continued for 10 to 15 years with observation and utilization of global geophysical data such as precipitation, snow, water vapor, aerosol, for climate change prediction, water management, and food security.

GCOM-W was launched on May 17, 2012, via a H-IIA rocket, and it flies in a Sun-synchronous orbit as part of the "A-train" satellite constellation.

Through use of its SGLI (Second generation GLobal Imager) optical instrument, it will collect data related to the carbon cycle and radiation budget, such as measurements of clouds, aerosols, ocean color, vegetation, and snow and ice.

From its Sun-synchronous orbit (altitude 798 km), SGLI will collect a complete picture of Earth every 2–3 days with a resolution of 250-1000m, across the UV, visible, and infrared spectrums.

By rotating a disc antenna (diameter 2.0 m) in 1.5 s period, it scans the Earth surface along an arc of 1450 km length.

SGLI (Second-generation Global Imager) is a multi-band optical radiometer and the successor of GLI sensor on ADEOS-II.

The lesson of GLI sensor's too big and too complicated structure, SGLI is divided to two simple systems, and the number of channels have been minimized to really essential bands, aiming at better reliability and survivability.