Reprojecting Sentinel-3 OLCI Chlorophyll Bands

Hello,

I am trying to Reproject the Sentinel 3 data but I was not able to ‘grasp’ the right way to do it.
I really would like to understand exactly how to transform the ‘raw’ unprojected .nc file to a Geotiff georrerenced using snappy library in Python.
Can someone please help me?

I really need to solve this. I’ve read many other threads but I am still not able to do it.
Thanks in advance.

It is better to open the xfdumanifest.xml file with snappy instead of working with the single netcdf files. The netcdf files have no geo-information. The geo-information is in tie_geo_coordinates.nc and geo_coordinates.nc. You would need to manually combine this information.
If you open the xfdumanifest.xml the data is georeferenced automatically for and you can reproject the data and export to geotiff.

Many thanks for the prompt answer. Fortunately I was able to find the solution. Sharing my code for future reference of other users:

def reprojecting():
p = ProductIO.readProduct({path} + “xfdumanifest.xml”)
HashMap = snappy.jpy.get_type(‘java.util.HashMap’)
parProj = HashMap()
parProj.put(‘crs’,‘GEOGCS[“WGS84(DD)”,’
‘DATUM[“WGS84”,’
‘SPHEROID[“WGS84”, 6378137.0, 298.257223563]],’
‘PRIMEM[“Greenwich”, 0.0],’
'UNIT[“degree”, 0.017453292519943295], ’
‘AXIS[“Geodetic longitude”, EAST],’
‘AXIS[“Geodetic latitude”, NORTH]]’)
parProj.put(‘resampling’, “Nearest”)
parProj.put(“orthorectify”, “false”)
parProj.put(“noDataValue”, -32768.0)
parProj.put(“includeTiePointGrids”, “false”)
parProj.put(“addDeltaBands”, “false”)
outProj = GPF.createProduct(“Reproject”, parProj, p)
ProductIO.writeProduct(outProj,{path} + “file_reprojected.nc”, ‘NetCDF-CF’)

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