Add e_per_area to bucket cache

Author: imreddyTeja

src/standalone/Bucket/Bucket.jl

@@ -321,6 +321,7 @@ auxiliary_types(::BucketModel{FT}) where {FT} = (
     FT,
     FT,
     ClimaCore.Geometry.WVector{FT},
+    FT,
 )
 auxiliary_vars(::BucketModel) = (
     :q_sfc,
@@ -336,6 +337,7 @@ auxiliary_vars(::BucketModel) = (
     :snow_melt,
     :infiltration,
     :top_bc_wvec,
+    :e_per_area,
 )
 auxiliary_domain_names(::BucketModel) = (
     :surface,
@@ -351,6 +353,7 @@ auxiliary_domain_names(::BucketModel) = (
     :surface,
     :surface,
     :surface,
+    :surface,
 )
 
 
@@ -497,6 +500,8 @@ function make_update_aux(model::BucketModel{FT}) where {FT}
             model.parameters.W_f,
         ) # Equation (2) of the text.
 
+        # Compute the integrated energy per area
+        ClimaLand.total_energy_per_area!(p.bucket.e_per_area, model, Y, p, t)
     end
     return update_aux!
 end
@@ -576,6 +581,38 @@ function surface_air_density(
     return p.bucket.ρ_sfc
 end
 
+"""
+
+    ClimaLand.total_energy_per_area!(
+        surface_field,
+        model::BucketModel,
+        Y,
+        p,
+        t,
+    )
+
+A function which updates `surface_field` in place with the value for
+the total energy per unit ground area for the `BucketModel`.
+"""
+function ClimaLand.total_energy_per_area!(
+    surface_field,
+    model::BucketModel,
+    Y,
+    p,
+    t,
+)
+    surface_field .= 0
+    ClimaCore.Operators.column_integral_definite!(
+        surface_field,
+        model.parameters.ρc_soil .* Y.bucket.T,
+    )
+
+    surface_field .+=
+        -LP.LH_f0(model.parameters.earth_param_set) .*
+        LP.ρ_cloud_liq(model.parameters.earth_param_set) .* Y.bucket.σS
+    return nothing
+end
+
 include("./bucket_parameterizations.jl")
 
 end