Running the NPZD with BuoyancyTracer()

[iuryt]

The current documentation mention that the temperature sensitivity in the list of equations that are solved for NPZD model. Therefore, the model does not run without :T.

Returning:

ArgumentError: The biogeochemical model you have selected requires (:N, :P, :Z, :D, :T).
You have specified some but not all of these as tracers so may be attempting
to use them for a different purpose. Please either specify all of the required
fields, or none and allow them to be automatically added.

On the code:

OceanBioME.jl/src/Models/AdvectedPopulations/NPZD.jl

Line 221 in db05016

@inline Q₁₀(T) = 1.88 ^ (T / 10) # T in °C

Can we do a straightforward implementation for NPZD with constant temperature or no temperature sensitivity?
Maybe something like NutrientPhytoplanktonZooplanktonDetritus(; grid, T=10)

There are reasons why we should be able to run the simulation on buoyancy only, especially for expensive process model simulations. A workaround could be to run with the temperature only and use SeawaterBuoyancy(constant_salinity = true).

What do you all think?

Edit: I was previously saying that the docs were not mentioning it, but I just realized it is mentioning, but it is not explicit that there is no way to set a constant temperature or run with BuoyancyTracer()

[jagoosw]

A way you could do it with a buoyancy tracer is to manually set the tracers like tracers=(:N, :P, :Z, :D, :b) and add T as an auxiliary field like auxiliary_fields = (; T = ConstantField(10))

[jagoosw]

I guess we could also make T an optional dependency but it might not be the most straightforward.

If we changed the model to be discrete form we could just add a parameter like temperature_sensetivity then whenever we need Q_10 write:

Q_10 = compute_temperature_sensetivity(bgc, fields)

and dispatch like

compute_temperature_sensetivity(::NPZD{Nothing}, fields) = 1

[iuryt]

A way you could do it with a buoyancy tracer is to manually set the tracers like tracers=(:N, :P, :Z, :D, :b) and add T as an auxiliary field like auxiliary_fields = (; T = ConstantField(10))

I tried that and it still returns the same error probably because of this line?

OceanBioME.jl/src/Models/AdvectedPopulations/NPZD.jl

Line 216 in db05016

required_biogeochemical_tracers(::NPZD) = (:N, :P, :Z, :D, :T)

Example:

#--------------- Instantiate Model
forcing = (;
    u=mom_sponge, v=mom_sponge, w=mom_sponge,
)


#eventually, try different buoyancy
model = NonhydrostaticModel(grid = grid, 
                            biogeochemistry=biogeochemistry,
                            advection = WENO(; grid),
                            coriolis = coriolis,
                            closure = (horizontal_closure,vertical_closure),
                            tracers = (:b, :N, :P, :Z, :D),
                            buoyancy = BuoyancyTracer(),
                            forcing = forcing,
                            boundary_conditions = (u=u_bcs, v=v_bcs),
                            auxiliary_fields = (; T = ConstantField(10)))

[iuryt]

@jagoosw
I think that we could add the option that if T is not in the tracers, it should be in the auxiliary_fields, but I can see that it might not be a straightforward implementation.

OceanBioME.jl/src/Models/AdvectedPopulations/NPZD.jl

Lines 216 to 217 in db05016

	required_biogeochemical_tracers(::NPZD) = (:N, :P, :Z, :D, :T)
	required_biogeochemical_auxiliary_fields(::NPZD) = (:PAR, )

[jagoosw]

This will be solved (kind of) by #355