Getting the correct visualisation with wplot using additional parameters and values

VISAN
1

Hello everybody,

I have downloaded the file “S5P_OFFL_L2__CH4____20210201T101856_20210201T120026_17125_01_010400_20210203T150228.nc” from the Sentinel-5P Pre-Operations Data Hub.

When I open the file with VISAN, I get this:

2021-03-02 (2)
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With these two commands, I get the following picture:

product = harp.import_product(r"CopernicusData\S5P_OFFL_L2__CH4____20210201T101856_20210201T120026_17125_01_010400_20210203T150228.nc")
wplot(product)

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2021-03-021911×1029 256 KB

By the way, why can I not choose another dataset? Is it a bug?

With these two commands, I get the following picture:

product = harp.import_product(r"CopernicusData\S5P_OFFL_L2__CH4____20210201T101856_20210201T120026_17125_01_010400_20210203T150228.nc")
wplot(product, value=‘CH4_column_volume_mixing_ratio_dry_air_validity’)

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How do I know which different values exist?
I do not see the variable “'CH4_column_volume_mixing_ratio_dry_air_validity” in the variable explorer of VISAN (first picture).

Can you please recommend helpful resources to get a better understanding of Sentinel5p data?

With best regards
space_enthusiast

2

This may indeed be a bit confusing.

The product browser in visan, which is your first screenshot, uses the coda interface to access the product. This interface will show you the file using the actual data format of the file.
You can also use coda yourself in visan to read data from products (see these python examples to see how), but it will be more difficult to turn this into plots.

The harp interface converts the product from its actual format (the format you can see with coda) to a harmonized harp format. This means that you will have a different structure, different variable names, etc. How harp performs these conversions is included in the documentation as well.

To see the variables in visan, simply print the product variable

print(product)

The product variable is just a python object, so you can perform all kinds of python operations on it. Again, the documentation is a good start to see how.

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