Missing data

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vwjerrod
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Missing data

by vwjerrod » Tue Aug 17, 2021 2:06 pm America/New_York

Hi there! I was comparing data for Sentinel-3A between your site (https://oceandata.sci.gsfc.nasa.gov) and the ESA site (https://scihub.copernicus.eu/dhus/#/home) and I noticed that about ~60 files were missing for the NT product on March 1 2021. I was just curious if there was a reason for that or if it was just a glitch in backfilling? Thank you so much for your help. Cheers.

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vwjerrod
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Re: Missing data

by vwjerrod » Tue Aug 17, 2021 5:03 pm America/New_York

I also found that on July 5 2016, there 4 less files that found on the ESA site.

OB ODPS - towens
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Re: Missing data

by OB ODPS - towens » Wed Aug 25, 2021 4:45 pm America/New_York

There are times when the OLCI is unavailable from our normal source and we pull data from an alternate source. When that occurs, the file names may be slightly different than what is available on the ESA archive and files that have the processing center LN1 at ESA may show MAR on our site. Can you be specific about the missing data. I see 233 S3A_OL_1_EFR files for March 1 on our archive.

Tommy

vwjerrod
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Re: Missing data

by vwjerrod » Thu Aug 26, 2021 9:58 am America/New_York

Hi Tommy thanks for the reply. Is there another archive to get the data from? From the archive I posted above https://oceandata.sci.gsfc.nasa.gov (/directaccess/S3AOLCI/L1/2021/060/) for March 1 2021 I get a total of 219 files and that includes S3A_OL_1_ERR as well as NR files. I've been trying to find only EFR/NT files and when I do that, I can only find 167 for that day. And when I search the ESA site for those parameters I get 231 files. If there is another place to get the files please let me know, it would be great. Thank you so much again for your help!

OB ODPS - towens
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Re: Missing data

by OB ODPS - towens » Thu Aug 26, 2021 10:50 am America/New_York

There appears to be missing data in the direct access directory listing that the web developers are working to correct.

You can try using the file search option:
https://oceandata.sci.gsfc.nasa.gov/api/file_search/

See if that gives you the files you are expecting.

Tommy

vwjerrod
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Re: Missing data

by vwjerrod » Thu Aug 26, 2021 11:22 am America/New_York

Hi Tommy, this works perfect! Thank you so much for bringing this to our attention! Thank you so much and have a great day!

vwjerrod
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Re: Missing data

by vwjerrod » Thu Aug 26, 2021 1:45 pm America/New_York

Hi again Tommy, this site is great and generally it looks a lot better as previously stated. Although on 2016-07-05 it appears that there is still a discrepancy of 4 files. I noticed though that as you stated earlier these are not from LN1 but say LR2, is that the designation for your sites processing? I haven't come across any that have the designation of MAR. Thanks for the clarification and all your help again so much.

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