S5P_NRTI_L2__SO2 is not properly read

snap
#1

Dear @marpet,

I have recently upgraded from SNAP 6.0 to SNAP 7.0, along with all the latest modules (module_list.txt)

Unfortunately I can no longer subset Sentinel-5P NRTI files (nc format). The Subset operator returns an error stating that the product has no geocoding:

RuntimeError: java.lang.IllegalArgumentException: Product without geo-coding.

I use snappy to process the products, here is an snippet:

from snappy import GPF
from snappy import ProductIO
from snappy import HashMap

# open product
fname = 'S5P_NRTI_L2__SO2____20181118T112353_20181118T112853_05691_01_010102_20181118T122344.nc'
p = ProductIO.readProduct(fname)

# subset product
parameters = HashMap()
parameters.put('copyMetadata', 'true')
parameters.put('geoRegion', 'POLYGON ((33.748 2.977, 24.752 2.977, 24.733 -6.007, 33.767 -6.007, 33.748 2.977))')
#parameters.put('sourceBands', 'sulfurdioxide_total_vertical_column_1km')
p = GPF.createProduct('Subset', parameters, p)

It seems that the band are no longer recognized/accessed properly: with SNAP 6 the recognized bands had names like “sulfurdioxide_total_vertical_column_1km”, whereas with SNAP 7 the same band is recognized as “sulfurdioxide_total_vertical_column_1km_PRODUCT/SUPPORT_DATA/DETAILED_RESULTS”.

Is there an easy fix to this? I use snappy to manage an operational monitoring framework using Sentinel-1, Sentinel-2, and Sentinel-5P products, so I would deeply like to stick with SNAP rather than try new toolboxes (e.g., BEAT).

Thanks in advance for any advice or suggestion!

Issue with subset in SNAP 7
#2

Hi seb,

I’ve created a new thread from your post. The title reflects better the issue.

The issue was introduced during the development of SNAP 7.
We came across NetCDF files where variables had the same names but but where contained in different groups. In SNAP products don’t have such hierachy of bands. Therefor we got conflicts, because of the same band name.
To solve this we extended the names by the group names.
Because Sentinel5p is not explitly supported by SNAP we haven’t noticed that we introduced a new issue here. Especially, the issue with the missing geo-coding.

In the next version of SNAP the geo-coding will be back and also the old band names. Band names are only modified when a naming conflict is detected.

This means for you that you can go back to version 6, or version 7 without the updates, or you wait a few weeks till SNAP 8 is released.

SNAP-1307 is the issue I’ve created.

#3

Dear @marpet,

many thanks for your detailed explanation and for opening the issue.

I’ll wait for version 8, and in the mean time use a docker container with version 6 to handle S5P products.

Thanks again for the support!