EAMxx: add possibility to dump a dictionary of the FieldManager field…

…s to a yaml file

components/eamxx/cime_config/namelist_defaults_scream.xml

@@ -717,6 +717,7 @@ be lost if SCREAM_HACK_XML is not enabled.
   <!-- driver_options options for scream -->
   <driver_options>
     <atmosphere_dag_verbosity_level>0</atmosphere_dag_verbosity_level>
+    <save_field_manager_dictionary type="logical">false</save_field_manager_dictionary>
     <atm_log_level type="string"
                    valid_values="trace,debug,info,warn,error"
                    doc="Verbosity level for the atm logger">

components/eamxx/src/control/atmosphere_driver.cpp

@@ -687,6 +687,25 @@ void AtmosphereDriver::create_fields()
 
   m_ad_status |= s_fields_created;
 
+  // If the user requested it, we can save a dictionary of the FM fields to file
+  auto& driver_options_pl = m_atm_params.sublist("driver_options");
+  if (driver_options_pl.get("save_field_manager_dictionary",false)) {
+    auto pg = m_grids_manager->get_grid("Physics");
+    const auto& fm = m_field_mgrs.at(pg->name());
+    ekat::ParameterList dict;
+    DefaultMetadata std_names;
+    for (const auto& it : *fm) {
+      const auto& fid = it.second->get_header().get_identifier();
+      auto& pl = dict.sublist(fid.name());
+
+      pl.set("units",fid.get_units().to_string());
+      pl.set("layout",fid.get_layout().names());
+      pl.set("standard_name",std_names.get_standardname(fid.name()));
+    }
+
+    ekat::write_yaml_file("eamxx_fields.yaml",dict);
+  }
+
   stop_timer("EAMxx::create_fields");
   stop_timer("EAMxx::init");
   m_atm_logger->info("[EAMxx] create_fields ... done!");