S3A-OLCI NR came after NT

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yuyuanxie
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Joined: Fri Mar 04, 2022 10:36 am America/New_York

S3A-OLCI NR came after NT

by yuyuanxie » Thu May 26, 2022 1:54 pm America/New_York

Hello,

https://oceandata.sci.gsfc.nasa.gov/directdataaccess/Level-1B/S3A-OLCI/2022/141/
I found in that directory; NR files came 3 days after NT files. My understanding is NT shall come after NR, and their sampling timestamp in filenames shall be the same. But you can see 5 seconds difference between the following two.
S3A_OL_1_EFR____20220521T003112_20220521T003412_20220525T135459_0179_085_273_2700_MAR_O_NR_002.zip 2022-05-25 14:26:37 596948088
S3A_OL_1_EFR____20220521T003117_20220521T003417_20220522T004931_0179_085_273_2700_PS1_O_NT_002.zip 2022-05-22 01:49:46 599880072

For this case, NR and NT, which is the mostly updated? Please advise.

Best regards!
-Yuyuan

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OB ODPS - towens
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Re: S3A-OLCI NR came after NT

by OB ODPS - towens » Thu May 26, 2022 2:34 pm America/New_York

The NT data are the refined stream.
It isn't clear to me why ESA would reprocess a Near Real Time granule 4 days after real time.
They may have been testing something internally and published it by mistake.
I would ignore the NR granule.

Tommy
Last edited by OB ODPS - towens on Thu May 26, 2022 11:22 pm America/New_York, edited 1 time in total.

yuyuanxie
Posts: 13
Joined: Fri Mar 04, 2022 10:36 am America/New_York

Re: S3A-OLCI NR came after NT

by yuyuanxie » Thu May 26, 2022 2:38 pm America/New_York

Awesome! Thanks, Tommy.

-Yuyuan

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