Detection of anomalies in the UV–vis reflectances from the Ozone Monitoring Instrument

Abstract. Various instrumental or geophysical artifacts, such as saturation, stray light obstruction of (either coming from the instrument related to solar eclipses), negatively impact satellite measured ultraviolet and visible Earthshine radiance spectra downstream retrievals atmospheric surface properties derived these spectra. In addition, excessive noise cosmic-ray impacts, prevalent within South Atlantic Anomaly, can also degrade measurements. Saturation specifically pertains observations very bright surfaces sunglint over open water thick clouds. When saturation occurs, additional photoelectric charge generated at saturated pixel may overflow pixels adjacent a area be reflected distorted image in final sensor output. effects cannot corrected an acceptable level for science-quality retrievals, flagging affected is indicated. Here, we introduce straightforward detection method that based on correlation, r, between observed irradiance 10 nm spectral range; our decorrelation index (DI brevity) simply defined DI 1−r. increases with anomalous additive either radiances, most likely cause data Ozone Monitoring Instrument (OMI), irradiances. relatively use interpret computed different wavelength intervals. We developed set DIs two channels OMI, hyperspectral pushbroom imaging spectrometer. For each OMI spatial measurement, define 14 wavelength-dependent channel (350–498 nm) six its 2 (UV2) (310–370 nm). As defined, reflect continuous range deviations reference spectrum are complementary binary possibility warning (SPW) flags currently provided individual set. Smaller values caused by number factors; this allows one obtain interesting physical results global distribution variations.