We’re using GPT to run orbit-calibration and terrain correction of Sentinel-1 scenes, and this mostly runs fine, but yesterday we had a correction error in some odd ways. I’ve coped the logs below, with some of the stacktraces clipped. The errors as I see them are:
- The scene is from November, but SNAP looks for the orbit file in http://step.esa.int/auxdata/orbits/Sentinel-1/POEORB/S1B/2018/12/, which would appear to be the path for December.
- It then tries https://qc.sentinel1.eo.esa.int/aux_resorb/S1A_OPER_AUX_RESORB_OPOD_20181122T163855_V20181122T123924_20181122T155654. In my experience the qc.sentinel.eo.esa.int domain has been very flaky, and often times out, so isn’t much good as a fallback. In this case though, SNAP appears to be looking for a Sentinel-1A orbit file, despite being given an S1B product.
We’re running SNAP version 6.0.0.
I’m not really sure what we’re doing wrong here. Any light you could shine on this would be appreciated.
$ gpt s1grd-preproc.xml -e -SSOURCE=in/S1B_IW_GRDH_1SDV_20181122T152655_20181122T152719_013719_019696_A045.SAFE POUTPUT=out/S1B_IW_GRDH_1SDV_20181122T152655_20181122T152719_013719_019696 -f GeoTIFF-BigTIFF
INFO: org.esa.snap.core.gpf.operators.tooladapter.ToolAdapterIO: Initializing external tool adapters
Executing processing graph
INFO: org.hsqldb.persist.Logger: dataFileCache open start
WARNING: org.esa.s1tbx.io.orbits.sentinel1.StepAuxdataScraper: Unable to connect to http://step.esa.int/auxdata/orbits/Sentinel-1/POEORB/S1B/2018/12/: HTTP error fetching URL
WARNING: org.esa.s1tbx.sar.gpf.orbits.ApplyOrbitFileOp: No valid orbit file found for 22-NOV-2018 15:25:51.000000
Orbit files may be downloaded from https://qc.sentinel1.eo.esa.int/
and placed in /home/gaiascope/.snap/auxdata/Orbits/Sentinel-1/POEORB/S1B/2018/11
WARNING: org.esa.s1tbx.io.orbits.sentinel1.StepAuxdataScraper: Unable to connect to http://step.esa.int/auxdata/orbits/Sentinel-1/RESORB/S1B/2018/12/: HTTP error fetching URL
INFO: org.esa.snap.engine_utilities.download.downloadablecontent.DownloadableContentImpl: http retrieving https://qc.sentinel1.eo.esa.int/aux_resorb/S1A_OPER_AUX_RESORB_OPOD_20181122T163855_V20181122T123924_20181122T155654
SEVERE: org.esa.snap.engine_utilities.download.downloadablecontent.DownloadableContentImpl: Failed to download remote file.
java.io.FileNotFoundException: https://qc.sentinel1.eo.esa.int/aux_resorb/S1A_OPER_AUX_RESORB_OPOD_20181122T163855_V20181122T123924_20181122T155654
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
[...]
INFO: org.esa.snap.engine_utilities.download.downloadablecontent.DownloadableContentImpl: http retrieving https://qc.sentinel1.eo.esa.int/aux_resorb/S1A_OPER_AUX_RESORB_OPOD_20181122T163855_V20181122T123924_20181122T155654
SEVERE: org.esa.snap.engine_utilities.download.downloadablecontent.DownloadableContentImpl: Failed to download remote file.
java.io.FileNotFoundException: https://qc.sentinel1.eo.esa.int/aux_resorb/S1A_OPER_AUX_RESORB_OPOD_20181122T163855_V20181122T123924_20181122T155654
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
[...]
WARNING: org.esa.s1tbx.sar.gpf.orbits.ApplyOrbitFileOp: ApplyOrbit ignoring error and continuing: org.esa.snap.core.gpf.OperatorException: No valid orbit file found for 22-NOV-2018 15:25:51.000000
Orbit files may be downloaded from https://qc.sentinel1.eo.esa.int/
and placed in /home/gaiascope/.snap/auxdata/Orbits/Sentinel-1/POEORB/S1B/2018/11
Entire image is outside of SRTM valid area.
Please use another DEM.
done.
org.esa.snap.core.gpf.graph.GraphException: [NodeId: Terrain-Correction] Entire image is outside of SRTM valid area.
Please use another DEM.
at org.esa.snap.core.gpf.graph.NodeContext.initTargetProduct(NodeContext.java:79)
[...]
Caused by: org.esa.snap.core.gpf.OperatorException: Entire image is outside of SRTM valid area.
Please use another DEM.
at org.esa.snap.engine_utilities.gpf.OperatorUtils.catchOperatorException(OperatorUtils.java:432)
at org.esa.s1tbx.sar.gpf.geometric.RangeDopplerGeocodingOp.initialize(RangeDopplerGeocodingOp.java:368)
at org.esa.snap.core.gpf.internal.OperatorContext.initializeOperator(OperatorContext.java:486)
at org.esa.snap.core.gpf.internal.OperatorContext.getTargetProduct(OperatorContext.java:273)
at org.esa.snap.core.gpf.Operator.getTargetProduct(Operator.java:387)
at org.esa.snap.core.gpf.graph.NodeContext.initTargetProduct(NodeContext.java:77)
... 28 more
Error: [NodeId: Terrain-Correction] Entire image is outside of SRTM valid area.
Please use another DEM.
EDITED TO ADD: Since I’ve submitted this, the colleague that passed this to me mentioned that the product is in the Barents Sea! This explains the failure to retrieve the DEM. Should this cause the orbit-file application to fail in this way, though?