Many earth-observing missions, with sensors covering spectral regions from ultraviolet to microwaves, have been developed and utilized for studies of changes in the Earth's land, oceans, atmosphere, and their interactions. These missions include the U.S. NASA's Earth Observing System (EOS) missions, the Suomi-National Polar-orbiting Partnership (S-NPP) mission, the Landsat 8 mission, the NOAA's Polar-orbiting Operational Environmental Satellite (POES) series, the ESA's MetOp and Sentinel series, the JAXA's Greenhouse gases Observing SATellite (GOSAT), Advanced Land Observation Satellite-2 (ALOS-2), and the joint NASA/JAXA GPM mission, the Indian Remote Sensing (IRS) satellite series, the South Korean Communication, Ocean and Meteorological Satellite (COMS), and the China's FY and HY satellite series. Successful development and operations of these missions and their applications have significantly contributed to recent progress of the Global Earth Observation System of Systems (GEOSS), which is being built as a public infrastructure interconnecting a diverse and growing array of instruments and systems for monitoring and forecasting changes in the global environment. Meanwhile, with technology advancements and design improvements, various follow-on and new missions are currently underway throughout the world, such as the U.S. Joint Polar Satellite System (JPSS) missions, the next generation of Geostationary Operational Environmental Satellite-R series (GOES-R), ESA's Sentinels and Earth Explorer missions, JAXA's Global Change Observation Missions (GCOM), GOSAT-2, the joint ESA/JAXA EarthCARE mission, and the next generation of China's FY and HY satellite series. In addition to these research and operational missions, many efforts and advances have been made for the development of commercial and low-cost small satellites. As more and more satellite observations and data products are made available to the science and user community, high quality calibration and characterization of individual sensors and accurate determination of their calibration consistency have become increasingly important and demanding. The establishment of CEOS reference standard test sites, development of a Quality Assurance Framework for Earth Observation (QA4EO) and the effort by the Global Space-based Inter-calibration System (GSICS) are such examples. 

In recognition of a new partnership between NASA and ISRO in developing a dual-frequency synthetic aperture radar mission named NISAR, this conference will include a special session on the mission.