The Application of Deep Convective Clouds in the Calibration and Response Monitoring of the Reflective Solar Bands of FY-3A/MERSI (Medium Resolution Spectral Imager)

Abstract

Based on simulated reflectance, deep convective clouds (DCC) can be used as an invariant target to monitor the radiometric response degradation of the FY-3A/MERSI (Medium Resolution Spectral Imager) reflective solar bands (RSBs). The long-term response of the MERSI RSBs can easily be predicted using a quadratic fit of the monthly DCC mean reflectance, except for bands 6 and 7, which suffer from instrument anomalies. DCC-based degradations show that the blue bands (λ < 500 nm) and water-vapor bands have degraded significantly, whereas for near-infrared bands, the total degradations in four years are within 3% (excluding bands 3 and 20). For most bands, the degradation rates are greatest during the first year in orbit and decrease over time. The FY-3A/MERSI degradation results derived from DCC are consistent within 2.5%, except for bands, 11, 18 and 19, when compared with Aqua/MODIS(Moderate Resolution Imaging Sepetroradiometer) inter-calibration, multi-site invariant earth target calibration and the CRCS(Chinese Radiometric Calibration Site) Dunhuang desert vicarious calibration methods. Overall, the 2σ/mean degradation uncertainty for most MERSI bands was within 3%, validating the temporal stability of the DCC monthly mean reflectances. The DCC method has reduced the degradation uncertainties for MERSI water vapor bands over other methods. This is a

In-Orbit Radiometric Calibration and Stability Monitoring of the PROBA-V Instrument

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“…confidence interval of mean of (rho_PV-rho_VGT2_sim)/rho_VGT2_sim in%; (4) Standard deviation associated to (rho_PV-rho_VGT2_sim)/rho_VGT2_sim in%; (5) Linear temporal trend in%/year; (6) 95% confidence interval of the linear temporal trend in%/year.…”

Inter-Band Radiometric Comparison and Calibration of ASTER Visible and Near-Infrared Bands

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In-flight intercalibration of FY-3C visible channels with AQUA MODIS

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