Merge pull request #1415 from CliMA/glw/ecco-init

Initialize OceananigansSimulation from the ECCO state estimate

Author: juliasloan25

experiments/ClimaEarth/components/ocean/oceananigans.jl

@@ -35,22 +35,19 @@ a surface area fraction field.
 This type is used to indicate that this simulation is an ocean simulation for
 dispatch in coupling.
 
-Specific details about the complexity of the model
-can be found in the Oceananigans.jl documentation.
+Specific details about the default model configuration
+can be found in the documentation for `ClimaOcean.ocean_simulation`.
 """
 function OceananigansSimulation(area_fraction, start_date, stop_date; output_dir, comms_ctx = ClimaComms.context())
     arch = comms_ctx.device isa ClimaComms.CUDADevice ? OC.GPU() : OC.CPU()
 
-    use_ecco = start_date + Dates.Month(1) < stop_date
-    if use_ecco
-        # Retrieve ECCO data (monthly)
-        # (It requires username and password)
-        dates = range(start_date, step = Dates.Month(1), stop = stop_date)
-        ecco_temperature = CO.Metadata(:temperature; dates, dataset = CO.ECCO.ECCO4Monthly())
-        ecco_salinity = CO.Metadata(:salinity; dates, dataset = CO.ECCO.ECCO4Monthly())
-        download_dataset(ecco_temperature)
-        download_dataset(ecco_salinity)
-    end
+    # Retrieve ECCO data (monthly)
+    # (It requires username and password)
+    dates = range(start_date, step = Dates.Month(1), stop = stop_date)
+    ecco_temperature = CO.Metadata(:temperature; dates, dataset = CO.ECCO.ECCO4Monthly())
+    ecco_salinity = CO.Metadata(:salinity; dates, dataset = CO.ECCO.ECCO4Monthly())
+    download_dataset(ecco_temperature)
+    download_dataset(ecco_salinity)
 
     # Set up ocean grid (1 degree)
     resolution_points = (360, 160, 32)
@@ -76,7 +73,9 @@ function OceananigansSimulation(area_fraction, start_date, stop_date; output_dir
 
     grid = OC.ImmersedBoundaryGrid(underlying_grid, OC.GridFittedBottom(bottom_height); active_cells_map = true)
 
-    if use_ecco
+    use_restoring = start_date + Dates.Month(1) < stop_date
+
+    if use_restoring
         # When we use ecco data, the forcing takes care of everything, including
         # the initial conditions
         restoring_rate = 1 / (3 * 86400)
@@ -92,16 +91,12 @@ function OceananigansSimulation(area_fraction, start_date, stop_date; output_dir
     # Create ocean simulation
     ocean = CO.ocean_simulation(grid; forcing)
 
-    if !use_ecco
-        T_init(λ, φ, z) = 30 * (1 - tanh((abs(φ) - 30) / 5)) / 2 + rand()
-        S_init(λ, φ, z) = 30 - 5e-3 * z + rand()
-        OC.set!(ocean.model, T = T_init, S = S_init)
-    end
+    # Set initial condition to ECCO state estimate at start_date
+    OC.set!(ocean.model, T = ecco_temperature[1], S = ecco_salinity[1])
 
     long_cc = OC.λnodes(grid, OC.Center(), OC.Center(), OC.Center())
     lat_cc = OC.φnodes(grid, OC.Center(), OC.Center(), OC.Center())
 
-
     # TODO: Go from 0 to Nx+1, Ny+1 (for halos) (for LatLongGrid)
 
     # Construct a remapper from the exchange grid to `Center, Center` fields