VIIRS Improvements Over MODIS

The National Oceanic and Atmospheric Administration (NOAA) and National Aeronautics and Space Administration (NASA) are jointly acquiring the next-generation civilian weather and environmental satellite system: the Joint Polar Satellite System (JPSS). The Joint Polar Satellite System will replace the afternoon orbit component and ground processing system of the current Polar-orbiting Operational Environmental Satellites (POES) managed by the National Oceanic and Atmospheric Administration. The Joint Polar Satellite System satellites will carry a suite of sensors designed to collect meteorological, oceanographic, climatological, and solar-geophysical observations of the earth, atmosphere, and space. The primary sensor for both SNPP and following JPSS missions is the Visible/Infrared Imager Radiometer Suite (VIIRS) developed by Raytheon Space and Airborne Systems (SAS). The ground processing system for the Joint Polar Satellite System is known as the Common Ground System (JPSS CGS), and provides command, control, and communications (C3) and data processing and product delivery. CGS was developed by Raytheon Intelligence and Information Systems (IIS). As a multi-mission system, CGS provides combinations of C3, data processing, and product delivery for numerous NASA, NOAA, Department of Defense (DoD), and international missions, such as NASA's Earth Observation System (EOS), NOAA's current POES, the Japan Aerospace Exploration Agency's (JAXA) Global Change Observation Mission – Water (GCOM-W1), and DoD's Defense Meteorological Satellite Program (DMSP).

The Moderate Resolution Imaging Spectroradiometer (MODIS) was developed by Raytheon SAS for the NASA Earth Observing System (EOS) as a research instrument to capture data in 36 spectral bands (from 0.4 ìm to 14.4 ìm and at varying spatial resolutions - 250 m, 500 m and 1 km). MODIS data provides unprecedented insight into cloud and aerosol characteristics, surface emissivity and processes occurring in the oceans, on land, and in the lower atmosphere. MODIS has flown on the Terra satellite since 1999 and on the Aqua satellite since 2002 and provided excellent data for scientific research and operational use for more than a decade. The value of MODIS-derived products for environmental monitoring motivated development of an operational counterpart for the next-generation polar-orbiting environmental satellites, the Visible/Infrared Imager Radiometer Suite (VIIRS). VIIRS combines the high value spectral coverage and radiometric accuracy of MODIS with the legacy spectral bands and radiometric accuracy of the Advanced Very High Resolution Radiometer (AVHRR) currently being flown on POES and the high spatial resolution (0.75 km) of the Operational Linescan System (OLS) on DMSP. Except for bands designed for deriving vertical temperature and humidity structure in the atmosphere, VIIRS uses identical or very similar bands from MODIS that are the most useful to operational customers in NOAA, the U.S. Air Force and the U.S. Navy. The development of VIIRS reaps the benefit of substantial investment in MODIS and the early development of operational algorithms using MODIS data. This presentation will cover the different aspects of transitioning a research system into an operational system. These aspects include: sensor operationalization, system performance operational factors, science changes to algorithms reflecting the operational performance factors, and the operationalization of the science into a fully 24 x 7 production system, tasked with meeting stringent operational needs. Finally, improvements in the end products will described, showing how the implementation of the improvements to MODIS in the VIIRS instrument, science, and data processing has resulted in major progress in product quality and utility.