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please visit the following page for OMNO2 L2 readme file

https://disc.sci.gsfc.nasa.gov/Aura/data-holdings/OMI/documents/v003/OMNO2_readme_v003.pdf
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2019/12/24

Collection 3 version 4 overpass files available

2019/12/06

Collection 3 version 4 data coming soon!
All overpass and L3 files will be reprocessed!
 
2018/08/15

 Reprocessed ovp files starting o74701 (07/31/22Z) to o74887

2018/06/27

 New version of OMNO2 overpass files

2018/06/20

 New version of OMNO2 overpass files are under processing

2017/03/27

 OMI transitioned into survival mode!
 NO data between o67327 (03/12) and o67402 (03/17)

2017/01/09
 Reprocessed OMI overpass files for orbits 66247-66242 and 66308-66323

2016/08/26

 Overpass files reprocessed for version 3.0

 The current version 3.0 of the OMI NO2 standard product improves on the retrievals
 in the previously published version 2.1 (July 2012) in a number of significant ways.
 The major improvements include:
 (1) an improved spectral fitting algorithm for retrieving slant column densities,
     including the use of monthly mean solar spectral irradiances;
 (2) improved resolution (1 deg. latitude and 1.25 deg. longitude) a priori NO2 profiles
     from Global Modeling Initiative chemistry-transport model with yearly varying emissions. 

 Warning: the precision estimates are preliminary and could change in the future.

 ### Read format has been changed ###
 ### Slant Column Amount O3 and Fit Quality Flags have been deleted ###

2016/08/12

 Overpass files will be reprocessed for a newer version of OMNO2 L2

2016/06/27

 Reprocessed overpass files for orbits 62345 - 63480
 (due to the KNMI request to start using the NSIDC issued daily NISE maps)

2015/03/16

 Reprocessed overpass files for orbits 56216 - 56335
 (due to Norway data recovery issue)

2014/12/11

 Reprocessed overpass files for orbits 55133 - 55148

2014/11/28

 Reprocessed overpass files for orbits 53594 - 54616
 (2014/08/12 13Z - 2014/10/21 17Z) for row anomaly correction

2013/08/12

 Reprocessed overpass files for orbit 48175-48189

2013/08/05

 Reprocessed overpass files for orbit 46892-46925
 due to a solar eclipse problem that occurred during this time

2013/02/25

 Reprocessed overpass files between
 orbit 42788 (07/31/12) and orbit 45381 (01/25/13)
 due to a new set of row anomaly flags from KNMI

2012/08/29

 Reprocessed overpass files between
 orbit 41324 (04/21/12) and orbit 42898 (08/08/12)
 due to L1B flag table update

2012/07/24

 reprocessed OMNO2 L2 for PGE v1.1.13.0
 AMF -> Amf
 VCD -> Vcd

2011/12/05

 Overpass files for the reprocessed OMNO2 L2 with all pixels
 that are not affected by OMI row anomalies (XTrackQualityFlags=0)

 The new overpass files have deleted the following variables
 NO2Unpol  : Column Amount NO2 Unpolluted
 NO2blwCld : NO2 polluted colummn density

 Variables added:
 NO2Std    : Column Amount NO2 Precision
 NO2Stra   : Column Amount NO2 Stratosphere
 NO2StraStd: Column Amount NO2 Stra Precision
 NO2TropStd: Column Amount NO2 Trop Precision
 DspSlntNO2: Destriped Slant Column Amount NO2