Conversion of units

Hi,

I have Sentinel-5P images such as: NO2, SO2 and O3. Their units are: mol/m2 but I would like to change them to µg/m^3.

I have used this syntax: “derive(” + harp_variable + " {time} [µg/m^3])",
But give me an error. What is the correct syntax to do it?

Be aware that you cannot derive a surface concentration from a total column. See also this post. You can derive an integrated column [µg/m^2], but not a concentration [µg/m^3] (unless you want some average concentration for the full column, but I am not sure that will make a lot of sense for these molecules).

To derive a total column mass density, you will have to use the proper variable name for the mass density (which has a different name from the volume/number density), e.g. derive(SO2_column_density {time} [ug/m^2]).