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OLCI level 1 raw data geo-offset along GreatLakes?

Posted: Thu Mar 30, 2023 4:57 pm America/New_York
by eccc_modis
Hello all, I work on Sentinel-3 OLCI level 1 images of the Great Lakes, and notice some raw images seems have geolocation offset when comparing with higher resolution Landsat-8 images sensed a few days apart.
the following are two examples from my test at early June 2017. both show offset along the south shore of the peninsula/islands.
site 1 (Lake Superior)
Landsat-8 true color reference:
LSuper_LST8_small.png
LSuper_LST8_small.png (276.75 KiB) Not viewed yet
OLCI level 1:
Lake Superior (S3A_OL_1_EFR____20170613T161541_20170613T161841_20180502T203026_0179_018_368_2160_LR2_R_NT_002)
Lake Superior (S3A_OL_1_EFR____20170613T161541_20170613T161841_20180502T203026_0179_018_368_2160_LR2_R_NT_002)
LSuper_OLCI.png (313.95 KiB) Not viewed yet
site 2 (Lake Ontario)
Landsat-8 true color reference:
OLCI level 1:
Lake Ontario (S3A_OL_1_EFR____20170611T152704_20170611T153004_20180502T143746_0179_018_339_2160_LR2_R_NT_002)
Lake Ontario (S3A_OL_1_EFR____20170611T152704_20170611T153004_20180502T143746_0179_018_339_2160_LR2_R_NT_002)
LOnt_OLCI_small.png (465.22 KiB) Not viewed yet
all file above in my google drive https://drive.google.com/file/d/19DFjvTTUOymzK5HBxg0QryhMeU9NceUZ/view?usp=share_link
here are the data products I used for the test:
OLCI products: (download from : https://scihub.copernicus.eu)
S3A_OL_1_EFR____20170613T161541_20170613T161841_20180502T203026_0179_018_368_2160_LR2_R_NT_002
S3A_OL_1_EFR____20170611T152704_20170611T153004_20180502T143746_0179_018_339_2160_LR2_R_NT_002
Landsat-8 products: (download from : https://earthexplorer.usgs.gov/)
LC08_L1TP_025026_20170609_20200903_02_T1
LC08_L1TP_016029_20170610_20200903_02_T1

Thanks,
Chui,

Re: OLCI level 1 raw data geo-offset along GreatLakes?

Posted: Wed Apr 05, 2023 3:04 pm America/New_York
by OB.DAAC - SeanBailey
This is a question to bring up with the ESA or Eumetsat Copernicus teams. We do not control the geolocation process for the Sentinel missions.

Regards,
Sean

Re: OLCI level 1 raw data geo-offset along GreatLakes?

Posted: Thu May 25, 2023 11:41 am America/New_York
by eccc_modis
thank you Sean.
I will contact ESA then. I post here to see whether other users encounter the same geolocation offset issue, and whether it is caused by projection, software, tie-points, or other issues.
Chui,