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StandardTime problems - NetCDF datasets to multidimensional mosaic dataset

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3 weeks ago
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deltafox
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Good morning!

Can anyone help me in getting the dates (Standard Time) right when importing NetCDF files into an ArcGIS Pro (version 3.5.3) multidimensional mosaic dataset? I want to be able to make multidimensional mosaic datasets containing multiple NetCDF files, convert them to CRF (Cloud Raster Format) and then serve them as multidimensional layers in ArcGIS Enterprise.

Here is what I did and the problems I encounter (screenshots in png are referenced per step, and attached to the post):

 

1. Downloaded Daily Surface Soil Moisture NetCDF datasets from the Copernicus Browser: https://browser.dataspace.copernicus.eu/.

01_CopernicusBrowser.png.

 

2. First I loaded a single NetCDF into ArcGIS Pro (Tab: Map > Group: Layer > Add Data: Dropdown list > Multidimensional Data).

02_Add-Data.png

03_Add-Data-Settings.png

 

3. When viewing the pop-up of a pixel, the right StandardTime of the data is shown, in this case 2025-09-01T00:00:00+00:00.

04_Popup-of-pixel-value.png

 

5. In the properties of the dataset the date of the data is also shown correctly.

05_NetCDF-multidimensional-properties.png

 

6. To make a multidimensional mosaic dataset from a collection of NetCDF files I followed these steps:

  1. Make a new Geodatabase and a new Mosaic Dataset.

06_GDB-MosaicDataset.png.

      2. Right-click the mosaic dataset > add rasters.

07_Add-rasters.png

08_Add-rasters-Raster-type-properties.png

09_Add-rasters-Raster-processing-Mosaic-Postprocessing-Options.png

       3. Run.

 

7. The multidimensional mosaic dataset is created and functions normally.

 

8. But, when looking at the attributes in the footprint, the dates of the data is incorrect. Instead of (for example) 2025-09-01T00:00:00+00:00, it shows 2526-08-29 12:00:00.

10_Attribute-table-of-Footprint.png

 

9. When interacting with the dataset through the Multidimensional tools all works fine, but unfortunately with the incorrect dates.

11_Multidimensional-dataset-interaction.png

 

10. So I guess the Standard Time field is filled by converting the value in the Time field to a date. So time value 203315 is converted to 2526-08-29 12:00:00.

12_Time-to-StandardTime.png

 

11. The time value didn’t seem right however. So I used ESA’s SNAP toolbox to inspect the value used for time. For this specific NetCDF file, the time value is shown as 20331.5 and not as 203315.

13_Time-value-in-NetCDF.png

 

12. So something goes wrong with this value when making the multidimensional mosaic dataset. As seen earlier (steps 2-4 above), when opening a single NetCDF in ArcGIS Pro the time value behaves normally and results in correct StandardTime values.

 

13. I tried a workaround – made a new OrigTime field in which the Time value is divided by 10: 203315 / 10 = 20331.5. But I cannot get this converted into the right Standard Time.

14_Tried-a-workaround.png

 

Is there a solution to this that does not involve “manual labour”? It will be impossible to edit values manually when hundreds of NetCDF’s are loaded into the multidimensional mosaic dataset.

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