Questions about the ROMS-fennel model nitrogen units.

[junbob]

I have a question that arose while generating model input data. According to ROMS/External/varinfo.dat, the input and output units for nitrate and ammonium are specified as millimole Nitrogen per meter³, and the river forcing variables for nitrate and ammonium have the same units. However, I noticed that the final output of my model presents the unit for nitrate as millimole NO₃ per meter³ and for ammonium as millimole NH₄ per meter³.

Here are my questions:

Should I convert all input data (NO₃, NH₄, river NO₃, and river NH₄) into millimole Nitrogen per meter³ before inputting it into the model?

If I input the data as millimole Nitrogen per meter³, does the model convert the units internally, resulting in outputs of mmol NO₃ per meter³ and mmol NH₄ per meter³?

Alternatively, do the outputs actually represent millimole Nitrogen per meter³, and I need to convert them to the specific units manually?

To summarize:

ROMS/External/varinfo.dat: Input/output for NO₃ and NH₄ → millimole Nitrogen per meter³
River forcing variables: Input for river NO₃ and NH₄ → millimole Nitrogen per meter³
My output results:
Output NO₃ → millimole NO₃ per meter³
Output NH₄ → millimole NH₄ per meter³

It's so confusing.
Please help me

[mjfconan]

hello,
I think they are the same units, because either NO₃ or NH₄ has only one nitrogen per molecule.

[kfennel]

Hello,

Mjfconan is correct. They are the same unit.

Cheers, Katja