NC to GeoTIFF Export sea surface temperature value has very strange

[suthagar]

Hi Greeting to all
I download Sea surface temperature, sea surface salinity data as netcdf format from this mentioned website (https://ncss.hycom.org/thredds/ncss/grid/ESPC-D-V02/ice/2025/dataset.html)

After I loaded that nc file in SNAP (which was clear sensible pixel value )

The second step I tried to convert nc file to GeoTIFF format. After then my sst band value i had peak

This issue happen on all the band SSS, SST, , u, v

I hope this can be solvable , Thank you for your time

[Marco_EOM]

The cause is probably that SNAP stores in GeoTiff files only the raw values.

I have explained possible solution here:

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[suthagar]

Good Morning

Thanks for your time, Yes I applied scale factor and addoffset Now get reliable pixel value

[suthagar]

Hi greeting to all

I have strange chl_oc4me band value after convert geotiff.

I converted to this file band named chl_oc4me
S3B_OL_2_WFR____20250114T043254_20250114T043554_20250114T062002_0180_102_090_2700_MAR_O_NR_003.SEN3

After convert value like this

I dont know what scale factor apply for chl_oc4me band , If know anyone kindly mention my mistake

Thank you

[muskan]

Hi everyone, thanks for the detailed explanations so far. For the issue with the chl_oc4me band values after conversion to GeoTIFF, have you tried checking the metadata in the original .nc file for any hints about the scale factor or offset? Sometimes these details are embedded in the file attributes. If not, tools like Python’s xarray might help inspect the file contents.

[Marco_EOM]

You can find the scale and offset value in the information window. Select the chl_oc4me band and open the information window.
See SNAP Online Help

If you use BandMaths to create a copy of the original band, you don’t need to know the values. They are applied automatically.