Assessment of S-NPP VIIRS On-orbit Radiometric Calibration and Performance.

Area of Science:

• Earth Observation
• Remote Sensing Technology
• Spacecraft Instrumentation

Background:

• The Visible Infrared Imaging Radiometer Suite (VIIRS) instrument on the Suomi-NPP spacecraft has been operational since October 2011.
• VIIRS generates environmental data records (EDR) from sensor data records (SDR) for operational and research applications.

Purpose of the Study:

• To review VIIRS sensor on-orbit calibration methodologies for reflective solar bands (RSB) and thermal emissive bands (TEB).
• To assess the on-orbit radiometric performance of VIIRS.
• To describe improvements in calibration and data quality.

Main Methods:

• Utilized measurements from instrument on-board calibrators (OBC) and lunar observations for radiometric performance assessment.
• Controlled temperatures of the on-board blackbody (BB) and cold focal plane assemblies for stability.
• Monitored and analyzed degradation in optical throughput and solar diffuser.

Main Results:

• All on-board calibrators (OBC) operated normally, enabling critical calibration parameter updates.
• Stable temperature control was maintained for the on-board blackbody (BB) and focal plane assemblies.
• Despite degradation in infrared bands and solar diffuser, VIIRS performance met design requirements.

Conclusions:

• VIIRS demonstrates robust radiometric performance and data quality, meeting mission objectives.
• Ongoing efforts focus on addressing identified challenges to further enhance sensor calibration and characterization.
• Continuous calibration and quality improvements ensure the long-term utility of VIIRS data for Earth science applications.