|Title||Updates of MODIS on-orbit calibration uncertainty assessments|
|Year of Publication||2017|
|Authors||Xiong, X., A. Angal, W. Barnes, H. Chen, V. Chiang, X. Geng, Y. Li, K. Twedt, Z. Wang, T. Wilson, and A. Wu|
|Proceedings||Proc. SPIE - Earth Observing Systems XXII|
|MCST Conference||SPIE - Earth Observing Systems XXII|
|Keywords||Aqua; calibration; characterization; MODIS; terra; traceability; uncertainty|
The Moderate Resolution Imaging Spectroradiometer (MODIS) instruments have successfully operated for more than 17 and 15 years, respectively, on-board the NASA’s Earth Observing System (EOS) Terra and Aqua spacecraft. MODIS level 1B (L1B) data products include top of the atmosphere (TOA) reflectance factors for the reflective solar bands (RSB) and radiances for both the RSB and the thermal emissive bands (TEB), and their associated uncertainty indices (UI) at a pixel-by-pixel level. This paper provides a brief review of MODIS L1B calibration algorithms, including improvements made in recent years. It presents an update of sensor calibration uncertainty assessments with a focus on several new contributors resulting from changes in sensor characteristics and on-orbit calibration approaches and the impact due to these changes on the L1B data quality. Also discussed in this paper are potential changes that could be made to continue improving the quality of MODIS L1B uncertainty product.