Georeference/Reprojecting Sentinel 3A Level 2 OLCI ChL_OC4ME

OK, so I am trying to make a GeoTiff image from your the Sentinel 3A Level 2 OLCI CHL_OC4ME band (file from CODA named S3A_OL_2RR*). I am interested in output the Chlorophyll product in a specific area of interest with a Mercator WGS-72 projection. I understand I first need to Georeference the band using the embedded geo_coordinates (lat and long bands) then maybe re-project or warp it then output that image as a GeoTIFF. I am having trouble finding the correct tools and workflow. Can you please help.

Thanks, Matthew Upton

Simply open the xfdumanifest.xml in SNAP.
Do the reprojection (Raster/Geometric Operations/Reprojection) and select the reprojection you like. Click the option not to reprojection the tie-points. Don’t save the product to disk yet.
Remove all bands except the OLCI CHL_OC4ME band. You can simply select the bands in the product explorer and hit the <DEL>-key. Actually, this should be possible by the Subset operation (Raster/Subset in the menu) but there is a little bug at the moment. That’s why you need to delete the bands manually.
This could also be done on the command line and performed on a stack of products if you need it.

I have reprojected and exported the sentinel image to GeoTiff, when I try to open it in ArcMap, i don’t know which band to use. In ArcCatalog, there are 9 bands and bands 1-5 have 9 sub-bands. Can you please help. Thank you!

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You can export each band separately. If all bands are in one GeoTIFF the names are not present.
There is an example on how to do it on an automated basis. It is for Sentinel 2, but you can adapt it to your needs.

Good day!
If i’m trying to georeference Sentinel 3A Level 2 OLCI ChL_OC4ME by using utility gpt and graph.xml (not via snap desktop), and i don’t want to reproject and georeference all products in archive, because it takes too much time. How can i do this? Are any algorithms to georeference manually?
Thanks for your attention!

Is there a way to create geo-referenced “.tiff” raster files containing “otci” which is available as otci.nc file. There are other files like geo_coordinates.nc and xfdumanifest.xml, which you had mentioned and suggested opening in SNAP.
Is there a way of creating a raster without using SNAP using python / gdal or some other scripts?
I have tried using gdal_translate but could not succeed it correctly creating a geo-referenced raster.