rm ice concentration from ocean

Author: juliasloan25

experiments/ClimaEarth/components/ocean/oceananigans.jl

@@ -22,7 +22,6 @@ It contains the following objects:
 - `ocean_properties::OPROP`: A NamedTuple of ocean properties and parameters
 - `remapping::REMAP`: Objects needed to remap from the exchange (spectral) grid to Oceananigans spaces.
 - `ocean_ice_fluxes::NT`: A NamedTuple of fluxes between the ocean and sea ice, computed at each coupling step.
-- `ice_concentration::SIC`: A ClimaCore Field representing the sea ice concentration on the ocean/sea ice grid.
 """
 struct OceananigansSimulation{SIM, A, OPROP, REMAP, NT, SIC} <:
        Interfacer.OceanModelSimulation
@@ -31,7 +30,6 @@ struct OceananigansSimulation{SIM, A, OPROP, REMAP, NT, SIC} <:
     ocean_properties::OPROP
     remapping::REMAP
     ocean_ice_fluxes::NT
-    ice_concentration::SIC
 end
 
 """
@@ -282,9 +280,11 @@ Interfacer.get_field(sim::OceananigansSimulation, ::Val{:surface_temperature}) =
 """
     FluxCalculator.update_turbulent_fluxes!(sim::OceananigansSimulation, fields)
 
-Update the turbulent fluxes in the simulation using the values stored in the coupler fields.
+Update the turbulent fluxes in the simulation using the values computed at this time step.
 These include latent heat flux, sensible heat flux, momentum fluxes, and moisture flux.
 
+The input fields are already area-weighted, so there's no need to weight them again.
+
 A note on sign conventions:
 SurfaceFluxes and Oceananigans both use the convention that a positive flux is an upward flux.
 No sign change is needed during the exchange, except for moisture/salinity fluxes:
@@ -327,11 +327,6 @@ function FluxCalculator.update_turbulent_fluxes!(sim::OceananigansSimulation, fi
         F_turb_ρτyz_cc,
     )
 
-    # Weight the ocean fluxes by (1 - ice concentration)
-    ice_concentration = OC.interior(sim.ice_concentration, :, :, 1)
-    oc_flux_u .= (1 .- ice_concentration) .* oc_flux_u
-    oc_flux_v .= (1 .- ice_concentration) .* oc_flux_v
-
     (; ocean_reference_density, ocean_heat_capacity, ocean_fresh_water_density) =
         sim.ocean_properties
 
@@ -349,10 +344,7 @@ function FluxCalculator.update_turbulent_fluxes!(sim::OceananigansSimulation, fi
     oc_flux_T = surface_flux(sim.ocean.model.tracers.T)
     OC.interior(oc_flux_T, :, :, 1) .=
         OC.interior(oc_flux_T, :, :, 1) .+
-        (1 .- ice_concentration) .* (
-            (remapped_F_lh .+ remapped_F_sh) ./
-            (ocean_reference_density * ocean_heat_capacity)
-        )
+        (remapped_F_lh .+ remapped_F_sh) ./ (ocean_reference_density * ocean_heat_capacity)
 
     # Add the part of the salinity flux that comes from the moisture flux, we also need to
     # add the component due to precipitation (that was done with the radiative fluxes)
@@ -365,25 +357,14 @@ function FluxCalculator.update_turbulent_fluxes!(sim::OceananigansSimulation, fi
     oc_flux_S = surface_flux(sim.ocean.model.tracers.S)
     surface_salinity = OC.interior(sim.ocean.model.tracers.S, :, :, 1)
     OC.interior(oc_flux_S, :, :, 1) .=
-        OC.interior(oc_flux_S, :, :, 1) .-
-        (1 .- ice_concentration) .* (surface_salinity .* moisture_fresh_water_flux)
+        OC.interior(oc_flux_S, :, :, 1) .- (surface_salinity .* moisture_fresh_water_flux)
     return nothing
 end
 
 function Interfacer.update_field!(sim::OceananigansSimulation, ::Val{:area_fraction}, field)
     sim.area_fraction .= field
     return nothing
 end
-# Note, ice_concentration is on the ocean/sea ice grid. This assumes the ocean and
-#  sea ice are using the same grid.
-function Interfacer.update_field!(
-    sim::OceananigansSimulation,
-    ::Val{:ice_concentration},
-    field,
-)
-    sim.ice_concentration .= field
-    return nothing
-end
 
 """
     FieldExchanger.update_sim!(sim::OceananigansSimulation, csf, area_fraction)
@@ -394,6 +375,10 @@ by the coupler.
 Update the portion of the surface_fluxes for T and S that is due to radiation and
 precipitation. The rest will be updated in `update_turbulent_fluxes!`.
 
+Unlike the turbulent fluxes, the radiative and precipitation fluxes need to be
+weighted by the ocean area fraction, since they provided from the atmosphere
+without any weighting.
+
 A note on sign conventions:
 ClimaAtmos and Oceananigans both use the convention that a positive flux is an upward flux.
 No sign change is needed during the exchange, except for precipitation/salinity fluxes.
@@ -404,13 +389,13 @@ so a sign change is needed when we convert from precipitation to salinity flux.
 function FieldExchanger.update_sim!(sim::OceananigansSimulation, csf, area_fraction)
     (; ocean_reference_density, ocean_heat_capacity, ocean_fresh_water_density) =
         sim.ocean_properties
-    ice_concentration = OC.interior(sim.ice_concentration, :, :, 1)
+    ocean_fraction = sim.area_fraction
 
     # Remap radiative flux onto scratch array; rename for clarity
     CC.Remapping.interpolate!(
         sim.remapping.scratch_arr1,
         sim.remapping.remapper_cc,
-        csf.F_radiative,
+        ocean_fraction .* csf.F_radiative,
     )
     remapped_F_radiative = sim.remapping.scratch_arr1
 
@@ -420,19 +405,18 @@ function FieldExchanger.update_sim!(sim::OceananigansSimulation, csf, area_fract
     # TODO document ordering of flux updates somewhere
     OC.interior(oc_flux_T, :, :, 1) .=
         OC.interior(oc_flux_T, :, :, 1) .+
-        (1 .- ice_concentration) .*
-        (remapped_F_radiative ./ (ocean_reference_density * ocean_heat_capacity))
+        remapped_F_radiative ./ (ocean_reference_density * ocean_heat_capacity)
 
     # Remap precipitation fields onto scratch arrays; rename for clarity
     CC.Remapping.interpolate!(
         sim.remapping.scratch_arr1,
         sim.remapping.remapper_cc,
-        csf.P_liq,
+        ocean_fraction .* csf.P_liq,
     )
     CC.Remapping.interpolate!(
         sim.remapping.scratch_arr2,
         sim.remapping.remapper_cc,
-        csf.P_snow,
+        ocean_fraction .* csf.P_snow,
     )
     remapped_P_liq = sim.remapping.scratch_arr1
     remapped_P_snow = sim.remapping.scratch_arr2
@@ -444,8 +428,7 @@ function FieldExchanger.update_sim!(sim::OceananigansSimulation, csf, area_fract
     surface_salinity_flux =
         OC.interior(sim.ocean.model.tracers.S, :, :, 1) .* precipitating_fresh_water_flux
     OC.interior(oc_flux_S, :, :, 1) .=
-        OC.interior(oc_flux_S, :, :, 1) .+
-        (1 .- ice_concentration) .* .-surface_salinity_flux
+        OC.interior(oc_flux_S, :, :, 1) .- surface_salinity_flux
     return nothing
 end