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Changyong Cao

Satellite Meteorology and Climatology Division

Chief, Satellite Calibration and Data Assimilation Branch

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To view Dr. Cao's complete list of publications, visit these account links:


photo of Changyong CaoChangyong Cao oversees the satellite instrument calibration and data assimilation branch which is responsible for the calibration and validation of all operational polar-orbiting and geostationary satellites at NOAA. He is the lead for the STAR radiance science team, lead for the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument calibration/validation team, and co-lead for the Advanced Baseline Imager (ABI) calibration working group (CWG). He joined NOAA in 1999 initially as the infrared sounder instrument scientist, and specializes in the calibration of radiometers onboard NOAA's operational environmental satellites. In addition to the operational prelaunch and postlaunch calibration, Changyong is responsible for developing and refining the methodology for inter-satellite calibration using the Simultaneous Nadir Overpass (SNO) method, which has become one of the cornerstones of the WMO/Global Space-based Intercalibration System (GSICS), has been widely used for on-orbit instrument performance evaluation for Earth observation satellites, and by many scientists for quantifying inter-satellite calibration biases in developing long-term time series for climate change detection studies.

Dr. Cao has broad research interests in satellite instrument performance characterization, exploration of novel uses of satellite observations especially for the VIIRS/DNB and imaging bands, new technologies such as artificial intelligence and machine learning, and time series analysis. He is advisor to the WMO/GSICS, and chaired the CEOS/WGCV (Committee on Earth Observation Satellites/Working Group on Calibration/Validation) from 2007-2008. He is the recipient of three gold and one silver medal from the Department of Commerce and NOAA for his achievements.

Before joining NOAA in 1999, Changyong was a senior scientist in remote sensing with the System Engineering and Technology Group at Lockheed Martin, NASA Stennis Space Center, where he supported a number of NASA projects, from hyperspectral spaceborne/airborne instrument preflight calibration, inflight radiometric and spectral calibration, validation and verification, to advanced remote sensing applications. He was an Assistant Professor and laboratory manager at Southern Illinois University in the early 1990s. Changyong received his Ph.D. degree in Geography specializing in remote sensing and geographic information systems from Louisiana State University in 1992. He received his Bachelor of Science degree in geography from Peking (Beijing) University in 1982.


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