Ensuring the SI Traceability of Satellite Measurements from the Next Generation Geostationary Imager GOES-R/ABI

To meet the demanding requirements for more accurate satellite data for numerical weather prediction, real-time storm warnings, and climate change detection, significant efforts have been made to ensure the SI traceability of the next generation geostationary imager GOES-R/ABI (Advanced Baseline Imager) through strong government technical oversight. The goal is to ensure pre-launch and post-launch SI traceability with small uncertainties, which is a major step forward compared to the current and past systems where this traceability is not well-defined. This paper presents the major efforts and plans by the GOES-R calibration working group towards SI traceability both pre-launch and post-launch for the reflective solar and infrared bands of ABI. This includes pre-launch NIST participation with transfer standards such as TXR, VXR, and SIRCUS, as well as the use of CLARREO for SI traceability on-orbit. Examples will be provided to demonstrate the approach to reduce uncertainties through inter-satellite calibration at the SNOs (Simultaneous Nadir Overpass) between CLARREO and GOES-R/ABI as well as selected calibration/validation sites.