Three Recent Data Anomalies
Three recent data anomalies have been observed in the OMI measurements in the VIS channel. These anomalies manifest themselves as suppressions in the radiance spectra, and are currently under investigation.
The anomalies are currently under investigation to examine whether correction for the signal suppressions can be implemented in the level 1b data. No correction has been implemented at the moment. It is recommended that the rows in question are not used for scientific data analysis from the start of the anomaly onwards until a correction in the level 1b data has been implemented.
Because current (Collection 3) level 1b and level 2 data, including the DOMINO data product, have not been flagged or corrected for these anomalies, data users should be cautious in using the OMI data. One effective way to ensure meaningful data analysis is by excluding all the data from the affected rows from the reported start date of the anomaly onwards. As an alternative, data users may set a flag based on the reported uncertainty in the NO2 slant column density. Preliminary results suggest that slant column errors (SlantColumnAmountNO2Std) > 1.7·1015 molecules cm-2 are strongly correlated with the affected rows.
For more information on the status of the OMI instrument and the level 1b data, please check this page