There are two diagnostic output fields that should be optional.

The column integrated modal values of the deposition flux
of aqueous so4 and the deposition flux of aqueous h2so4
should be optional.

This will be a non-BFB change sinde these values were
always output before and now the default is not to
create these fields and avoid the calculation.

Author: overfelt

components/eamxx/src/physics/mam/eamxx_mam_microphysics_process_interface.cpp

@@ -164,8 +164,12 @@ void MAMMicrophysics::set_grids(
   // Diagnostic fluxes
   const FieldLayout vector2d_nmodes =
       grid_->get_2d_vector_layout(nmodes, "nmodes");
-  add_field<Computed>("dqdt_so4_aqueous_chemistry", vector2d_nmodes, kg/m2/s,  grid_name);
-  add_field<Computed>("dqdt_h2so4_uptake", vector2d_nmodes, kg/m2/s,  grid_name);
+
+  extra_mam4_diags_ = m_params.get<bool>("extra_mam4_diags", false);
+  if (extra_mam4_diags_) {
+    add_field<Computed>("dqdt_so4_aqueous_chemistry_column_integrated_flux", vector2d_nmodes, kg/m2/s,  grid_name);
+    add_field<Computed>("dqdt_h2so4_aqueous_chemistry_column_integrated_flux", vector2d_nmodes, kg/m2/s,  grid_name);
+  }
 
   // ---------------------------------------------------------------------
   // These variables are "updated" or inputs/outputs for the process
@@ -451,7 +455,8 @@ void MAMMicrophysics::initialize_impl(const RunType run_type) {
       {"sfc_alb_dir_vis", {-1e10, 1e10}},       // FIXME
       {"snow_depth_land", {-1e10, 1e10}},       // FIXME
       {"surf_radiative_T", {-1e10, 1e10}},      // FIXME
-      {"dqdt_so4_aqueous_chemistry", {-1e10, 1e10}},      // FIXME
+      {"dqdt_so4_aqueous_chemistry_column_integrated_flux", {-1e10, 1e10}},      // FIXME
+      {"dqdt_h2so4_aqueous_chemistry_column_integrated_flux", {-1e10, 1e10}},      // FIXME
       {"dqdt_h2so4_uptake", {-1e10, 1e10}}       // FIXME
   };
   set_ranges_process(ranges_microphysics);
@@ -634,8 +639,12 @@ void MAMMicrophysics::run_impl(const double dt) {
       get_field_in("snow_depth_land").get_view<const Real *>();
 
   // Constituent fluxes
-  view_2d aqso4_flx = get_field_out("dqdt_so4_aqueous_chemistry").get_view<Real **>();
-  view_2d aqh2so4_flx = get_field_out("dqdt_h2so4_uptake").get_view<Real **>();
+  view_2d aqso4_flx;
+  view_2d aqh2so4_flx;
+  if (extra_mam4_diags_) {
+    aqso4_flx = get_field_out("dqdt_so4_aqueous_chemistry_column_integrated_flux").get_view<Real **>();
+    aqh2so4_flx = get_field_out("dqdt_h2so4_aqueous_chemistry_column_integrated_flux").get_view<Real **>();
+  }
 
   // climatology data for linear stratospheric chemistry
   // ozone (climatology) [vmr]
@@ -916,8 +925,12 @@ void MAMMicrophysics::run_impl(const double dt) {
           }
         }
         // These output values need to be put somewhere:
-        const auto aqso4_flx_col = ekat::subview(aqso4_flx, icol);  // deposition flux of so4 [mole/mole/s]
-        const auto aqh2so4_flx_col = ekat::subview(aqh2so4_flx, icol);  // deposition flux of h2so4 [mole/mole/s]
+        mam4::MicrophysDiagnosticArrays diagnostic_arrays;
+        if (extra_mam4_diags_) {
+        // deposition flux of so4 [kg/m2/s] and deposition flux of h2so4 [kg/m2/s]
+          diagnostic_arrays.aqso4_column_integrated_flux = ekat::subview(aqso4_flx, icol);  
+          diagnostic_arrays.aqh2so4_column_integrated_flux = ekat::subview(aqh2so4_flx, icol);  
+        }
         Real dflx_col[gas_pcnst] = {};  // deposition velocity [1/cm/s]
         Real dvel_col[gas_pcnst] = {};  // deposition flux [1/cm^2/s]
         // Output: values are dvel, dflx
@@ -937,7 +950,7 @@ void MAMMicrophysics::run_impl(const double dt) {
             offset_aerosol, config.linoz.o3_sfc, config.linoz.o3_tau,
             config.linoz.o3_lbl, dry_diameter_icol, wet_diameter_icol,
             wetdens_icol, dry_atm.phis(icol), cmfdqr, prain_icol, nevapr_icol,
-            work_set_het_icol, drydep_data, aqso4_flx_col,  aqh2so4_flx_col, dvel_col, dflx_col, progs);
+            work_set_het_icol, drydep_data, diagnostic_arrays, dvel_col, dflx_col, progs);
 
         team.team_barrier();
         // Update constituent fluxes with gas drydep fluxes (dflx)

components/eamxx/src/physics/mam/eamxx_mam_microphysics_process_interface.hpp

@@ -61,6 +61,9 @@ class MAMMicrophysics final : public MAMGenericInterface {
   void finalize_impl(){/*Do nothing*/};
 
  private:
+  // Output extra mam4xx diagnostics.
+  bool extra_mam4_diags_ = false;
+
   // The orbital year, used for zenith angle calculations:
   // If > 0, use constant orbital year for duration of simulation
   // If < 0, use year from timestamp for orbital parameters