Fw budget

[emmomp]

I've attempted to finish the freshwater budget tutorial based on Jan-Erik's start point. I also tidied up a few other things in the salt/salinity budgets.

All budgets

• Now based on r4 not r3
• Removed calls to 'transpose' as xarray takes care of dimension broadcasting
• Replaced array-like indexing with .isel to avoid mistakes

Fw budget

• Included the volume scale factor 'rstarfac' in budget terms as in the salinity budget
• Included WVELSTAR (vertical bolus flux) in calculation of 'ADVr_FW', the vertical advective flux of fw
• Included the (appropriately scaled) salinity forcing in the FW forcing 'G_Forcing_Fw'
• Plotted spatial and time series of budget terms as for salt/salinity
• Can't plot total residual as the FW diffusive flux is calculated as the residual of the total tendency, forcing, and advection terms.
• Have plotted the scaled Salinity diffusive flux for comparison - not sure how well these should match, there appears to be an offset between them so perhaps I've made a mis-step?

[andrewdelman]

Thanks very much!! The revised notebook looks great. We're actually making our way through these notebooks to update them for v4r4 and the new ECCO output file structure based on PO.DAAC. These are very helpful changes.

[ifenty]

@emmomp is there another way for us to output the FW diffusive flux so that one doesn't need to calculate it as a residual?

[emmomp]

Probably, but not sure which package you'd put it in. Currently DfX/Y_THETA and SALT are output in gad_calc_rhs.F as they are calculated for the advection-diffusion. Any user could add it manually via PTRACERS I guess, but given it's defined wrt Salinity it would be more efficient to calculate it wrt salinity, and add in to src/salt_integrate.F perhaps.