Important Information for OMI Data Users


Row Anomalies

Several row anomalies have occurred in the recent past. These anomalies affect the quality of the Level 1B and Level 2 data products. Please read this information carefully prior to using OMI data. Please respect the dates mentioned as the anomalies have occurred recently.


Anomaly 1:      Since June 25th, 2007,               cross-track scenes 53-54 (0-based).

Anomaly 2:      Since May 11th, 2008,               cross-track scenes 37-44 (0-based).

Anomaly 3:      Since January 24th, 2009,          cross-track scenes 27-44 (0-based).

Row Anomaly Behavior

Since “anomaly 3” the row anomaly exhibits a more dynamic behavior than before. Which rows are affected and to what extent varies with time. Please visit the “Overview” section of our detailed technical information page for the most up to date information and details.

Row Anomaly Corrections

These anomalies are known to the OMI team and are currently under investigation to examine whether corrections for the effects can be implemented in the Level 1b data. Please visit this information page regularly for updates on the status of corrections implemented and visit our detailed technical information page.

Row Anomaly Flagging

The Level 1B data are partially flagged for the anomalies listed above. We expect to provide appropriate flagging for the anomalies in the near future. Please visit our detailed technical information page for details on the current flagging status of the Level 1B and Level 2 products. 

Recommendations To Users

At the moment no corrections have been implemented in the operational Level 1B and Level 2 data. It is recommended not to use the affected cross-track scenes.

Please respect the dates mentioned above. All other OMI data, meaning other cross track scenes and earlier observations, is of optimal quality.

Level-3 products are being produced after filtering for the cross track scenes mentioned per anomaly. 

Instrument status

For more information on the status of the OMI instrument and the level 1b data, please check this page