Abstract
Significant improvements have been made in recent years for the earth observations via remote sensing instruments that are operated onboard the low earth orbit (LEO) and geostationary (GEO) satellites. For passive optical sensors, however, the reflective solar (RS) calibration remains extremely challenging in terms of their calibration traceability, accuracy, and consistency. Because of this, extensive efforts have been made during different phases of sensor pre-launch calibration and characterization; and through the use of various on-board calibrators over the entire mission of sensor on-orbit operations. This paper provides an overview of sensor RS calibration approaches and strategies developed and applied by different sensors, including the use of on-board solar diffuser and lunar observations. It demonstrates their applications using examples from Terra and Aqua MODIS, launched in 1999 and 2002, respectively, and S-NPP and N-20 VIIRS, launched in 2011 and 2017, respectively. Lessons and future efforts to be made to address various challenging issues are also discussed.
Improvements and Challenges of Sensor Reflective Solar Calibration
Significant improvements have been made in recent years for the earth observations via remote sensing instruments that are operated onboard the low earth orbit (LEO) and geostationary (GEO) satellites. For passive optical sensors, however, the reflective solar (RS) calibration remains extremely challenging in terms of their calibration traceability, accuracy, and consistency. Because of this, extensive efforts have been made during different phases of sensor pre-launch calibration and characterization; and through the use of various on-board calibrators over the entire mission of sensor on-orbit operations. This paper provides an overview of sensor RS calibration approaches and strategies developed and applied by different sensors, including the use of on-board solar diffuser and lunar observations. It demonstrates their applications using examples from Terra and Aqua MODIS, launched in 1999 and 2002, respectively, and S-NPP and N-20 VIIRS, launched in 2011 and 2017, respectively. Lessons and future efforts to be made to address various challenging issues are also discussed.