Alpha and Volscl impact RF output (#745)

Here we change where the scalers are applied so that the vol, aerosol, and total forcing outputs are updated appropriately. While this PR does not change hector output or behavior between the parameter name change, there are code-breaking changes that have been made to the ini files. The ini files are not backward compatible. 

---------

Co-authored-by: ptrscll <[email protected]>

data-raw/input_params.csv

@@ -100,10 +100,10 @@ forcing,rho_so2,n,n,y,-7.24E-06,W yr m-2 S Gg-1,IPCC AR6 radiative efficiency SO
 forcing,rho_nh3,n,n,y,-0.00208,W yr m-2 NH3 Tg-1,IPCC AR6 radiative efficiency NH3 (7.SM.1.3.1 of IPCC AR6)
 forcing,RF_misc,n,n,n,"""(csv)""",,Miscellaneous radiative forcings default set to 0
 forcing,RF_misc,n,n,y,0,,"Miscellaneous radiative forcings default set to 0, or read in from a input table, may be used to read in additional forcings not modeled by Hector (i.e. solar, bc on snow , contrails from)"
+forcing,aero_scalar,n,n,y,1,(unitless),scaling factor for aerosol forcing
+forcing,vol_scalar,n,n,y,1,(unitless),scaling factor for volcanic forcing
 temperature,S,n,n,y,3,degC,equilibrium climate sensitivity for 2xCO2
 temperature,diff,n,n,y,2.3,cm2 s-1,ocean heat diffusivity
-temperature,alpha,n,n,y,1,(unitless),scaling factor for aerosol forcing
-temperature,volscl,n,n,y,1,(unitless),scaling factor for volcanic forcing
 temperature,qco2,n,n,y,3.75,,CO2 RF (7.3.2 of IPCC AR6)
 temperature,tas_constrain,n,y,n,"""(csv)""",,"Optional global temperature constraint; If supplied, the model will use these data, ignoring what it calculates"
 bc,BC_emissions,n,y,y,"""(csv)""",,

inst/include/component_data.hpp

@@ -65,6 +65,8 @@
 #define D_RHO_OC "rho_oc"            // BC radiative efficiency
 #define D_RHO_SO2 "rho_so2"          // SO2 radiative efficiency
 #define D_RHO_NH3 "rho_nh3"          // NH3 radiative efficiency
+#define D_AERO_SCALE "aero_scalar"
+#define D_VOLCANIC_SCALE "vol_scalar"
 
 // halocarbon components
 #define D_RF_CF4 D_RF_PREFIX CF4_COMPONENT_BASE
@@ -397,8 +399,6 @@
 #define D_GMST "gmst"
 #define D_LO_WARMING_RATIO "lo_warming_ratio"
 #define D_DIFFUSIVITY "diff"
-#define D_AERO_SCALE "alpha"
-#define D_VOLCANIC_SCALE "volscl"
 #define D_FLUX_MIXED "heatflux_mixed"
 #define D_FLUX_INTERIOR "heatflux_interior"
 #define D_HEAT_FLUX "heatflux"

inst/include/forcing_component.hpp

@@ -118,7 +118,10 @@ class ForcingComponent : public IModelComponent {
   unitval
       rho_nh3; // (W yr m–2 Tg–1) IPCC AR6 radiative efficiency SO2 7.SM.1.3.1
 
-  // Aerosol parameters for aerosol-cloud interactions (RFaci) see equation
+  // Aerosol parameters
+  unitval alpha;  // aerosol forcing factor, unitless
+  unitval volscl; // volcanic forcing scaling factor, unitless
+  // Parameters for aerosol-cloud interactions (RFaci) see equation
   // Equation 7.SM.1.2 of IPCC AR6
   double const aci_beta = 2.279759; //  Dorheim et al. 2024
   double const s_BCOC = 111.05064063; // (Tg C yr-1) IPCC AR6 7.SM.1.3.1

inst/include/temperature_component.hpp

@@ -145,8 +145,6 @@ class TemperatureComponent : public IModelComponent {
   // Model parameters
   unitval S;      //!< climate sensitivity for 2xCO2, deg C
   unitval diff;   //!< ocean heat diffusivity, cm2/s
-  unitval alpha;  //!< aerosol forcing factor, unitless
-  unitval volscl; //!< volcanic forcing scaling factor, unitless
 
   // Model outputs
   unitval tas;       //!< global average air temperature anomaly, deg C

inst/input/hector_ssp119.ini

@@ -162,6 +162,8 @@ baseyear=1750		; when to start reporting; by definition, all F=0 in this year
 
 ; Optional radiative forcing constraint
 ;RF_tot_constrain=csv:tables/CONSTRAINT.csv
+aero_scalar=1.0		; (unitless) uncertainty scaling factor for volcanic forcing
+vol_scalar=1.0		; (unitless) uncertainty scaling factor for volcanic forcing
 delta_co2=0.05		; (unitless) forcing tropospheric adjustments for CO2 (7.3.2.1 of IPCC AR6)
 delta_ch4=-.14		; (unitless) forcing tropospheric adjustments for CH4 (7.3.2.2 of IPCC AR6)
 delta_n2o=0.07		; (unitless) forcing tropospheric adjustments for N2O (7.3.2.3 of IPCC AR6)
@@ -179,8 +181,6 @@ RF_misc[1750]=0
 [temperature]
 S=3.0 			; equilibrium climate sensitivity for 2xCO2 degC (A.4.4 of IPCC AR6)
 diff=2.38		; ocean heat diffusivity, cm2/s calibrated to historical observations Dorheim et al. 2024 for details
-alpha=1.0     	; uncertainty scaling factor for aerosol forcing
-volscl=1.0    	; uncertainty scaling factor for volcanic forcing
 qco2=3.75     	; 2×CO2 RF (7.3.2 of IPCC AR6)
 
 ; Optional global temperature constraint

inst/input/hector_ssp126.ini

@@ -162,6 +162,8 @@ baseyear=1750		; when to start reporting; by definition, all F=0 in this year
 
 ; Optional radiative forcing constraint
 ;RF_tot_constrain=csv:tables/CONSTRAINT.csv
+aero_scalar=1.0     		; uncertainty scaling factor for aerosol forcing
+vol_scalar=1.0    		; uncertainty scaling factor for volcanic forcing
 delta_co2=0.05		; (unitless) forcing tropospheric adjustments for CO2 (7.3.2.1 of IPCC AR6)
 delta_ch4=-.14		; (unitless) forcing tropospheric adjustments for CH4 (7.3.2.2 of IPCC AR6)
 delta_n2o=0.07		; (unitless) forcing tropospheric adjustments for N2O (7.3.2.3 of IPCC AR6)
@@ -179,8 +181,6 @@ RF_misc[1750]=0
 [temperature]
 S=3.0 			; equilibrium climate sensitivity for 2xCO2 degC (A.4.4 of IPCC AR6)
 diff=2.38		; ocean heat diffusivity, cm2/s calibrated to historical observations Dorheim et al. 2024 for details
-alpha=1.0     	; uncertainty scaling factor for aerosol forcing
-volscl=1.0    	; uncertainty scaling factor for volcanic forcing
 qco2=3.75     	; 2×CO2 RF (7.3.2 of IPCC AR6)
 
 ; Optional global temperature constraint

inst/input/hector_ssp245.ini

@@ -162,6 +162,8 @@ baseyear=1750		; when to start reporting; by definition, all F=0 in this year
 
 ; Optional radiative forcing constraint
 ;RF_tot_constrain=csv:tables/CONSTRAINT.csv
+aero_scalar=1.0		; (unitless) uncertainty scaling factor for volcanic forcing
+vol_scalar=1.0		; (unitless) uncertainty scaling factor for volcanic forcing
 delta_co2=0.05		; (unitless) forcing tropospheric adjustments for CO2 (7.3.2.1 of IPCC AR6)
 delta_ch4=-.14		; (unitless) forcing tropospheric adjustments for CH4 (7.3.2.2 of IPCC AR6)
 delta_n2o=0.07		; (unitless) forcing tropospheric adjustments for N2O (7.3.2.3 of IPCC AR6)
@@ -179,8 +181,6 @@ RF_misc[1750]=0
 [temperature]
 S=3.0 			; equilibrium climate sensitivity for 2xCO2 degC (A.4.4 of IPCC AR6)
 diff=2.38		; ocean heat diffusivity, cm2/s calibrated to historical observations Dorheim et al. 2024 for details
-alpha=1.0     	; uncertainty scaling factor for aerosol forcing
-volscl=1.0    	; uncertainty scaling factor for volcanic forcing
 qco2=3.75     	; 2×CO2 RF (7.3.2 of IPCC AR6)
 
 ; Optional global temperature constraint

inst/input/hector_ssp370.ini

@@ -162,6 +162,8 @@ baseyear=1750		; when to start reporting; by definition, all F=0 in this year
 
 ; Optional radiative forcing constraint
 ;RF_tot_constrain=csv:tables/CONSTRAINT.csv
+aero_scalar=1.0     		; uncertainty scaling factor for aerosol forcing
+vol_scalar=1.0    		; uncertainty scaling factor for volcanic forcing
 delta_co2=0.05		; (unitless) forcing tropospheric adjustments for CO2 (7.3.2.1 of IPCC AR6)
 delta_ch4=-.14		; (unitless) forcing tropospheric adjustments for CH4 (7.3.2.2 of IPCC AR6)
 delta_n2o=0.07		; (unitless) forcing tropospheric adjustments for N2O (7.3.2.3 of IPCC AR6)
@@ -179,8 +181,6 @@ RF_misc[1750]=0
 [temperature]
 S=3.0 			; equilibrium climate sensitivity for 2xCO2 degC (A.4.4 of IPCC AR6)
 diff=2.38		; ocean heat diffusivity, cm2/s calibrated to historical observations Dorheim et al. 2024 for details
-alpha=1.0     	; uncertainty scaling factor for aerosol forcing
-volscl=1.0    	; uncertainty scaling factor for volcanic forcing
 qco2=3.75     	; 2×CO2 RF (7.3.2 of IPCC AR6)
 
 ; Optional global temperature constraint

inst/input/hector_ssp434.ini

@@ -162,6 +162,8 @@ baseyear=1750		; when to start reporting; by definition, all F=0 in this year
 
 ; Optional radiative forcing constraint
 ;RF_tot_constrain=csv:tables/CONSTRAINT.csv
+aero_scalar=1.0     		; uncertainty scaling factor for aerosol forcing
+vol_scalar=1.0    		; uncertainty scaling factor for volcanic forcing
 delta_co2=0.05		; (unitless) forcing tropospheric adjustments for CO2 (7.3.2.1 of IPCC AR6)
 delta_ch4=-.14		; (unitless) forcing tropospheric adjustments for CH4 (7.3.2.2 of IPCC AR6)
 delta_n2o=0.07		; (unitless) forcing tropospheric adjustments for N2O (7.3.2.3 of IPCC AR6)
@@ -179,8 +181,6 @@ RF_misc[1750]=0
 [temperature]
 S=3.0 			; equilibrium climate sensitivity for 2xCO2 degC (A.4.4 of IPCC AR6)
 diff=2.38		; ocean heat diffusivity, cm2/s calibrated to historical observations Dorheim et al. 2024 for details
-alpha=1.0     	; uncertainty scaling factor for aerosol forcing
-volscl=1.0    	; uncertainty scaling factor for volcanic forcing
 qco2=3.75     	; 2×CO2 RF (7.3.2 of IPCC AR6)
 
 ; Optional global temperature constraint

inst/input/hector_ssp460.ini

@@ -162,6 +162,8 @@ baseyear=1750		; when to start reporting; by definition, all F=0 in this year
 
 ; Optional radiative forcing constraint
 ;RF_tot_constrain=csv:tables/CONSTRAINT.csv
+aero_scalar=1.0     		; uncertainty scaling factor for aerosol forcing
+vol_scalar=1.0    		; uncertainty scaling factor for volcanic forcing
 delta_co2=0.05		; (unitless) forcing tropospheric adjustments for CO2 (7.3.2.1 of IPCC AR6)
 delta_ch4=-.14		; (unitless) forcing tropospheric adjustments for CH4 (7.3.2.2 of IPCC AR6)
 delta_n2o=0.07		; (unitless) forcing tropospheric adjustments for N2O (7.3.2.3 of IPCC AR6)
@@ -179,8 +181,6 @@ RF_misc[1750]=0
 [temperature]
 S=3.0 			; equilibrium climate sensitivity for 2xCO2 degC (A.4.4 of IPCC AR6)
 diff=2.38		; ocean heat diffusivity, cm2/s calibrated to historical observations Dorheim et al. 2024 for details
-alpha=1.0     	; uncertainty scaling factor for aerosol forcing
-volscl=1.0    	; uncertainty scaling factor for volcanic forcing
 qco2=3.75     	; 2×CO2 RF (7.3.2 of IPCC AR6)
 
 ; Optional global temperature constraint

inst/input/hector_ssp534-over.ini

@@ -162,6 +162,8 @@ baseyear=1750		; when to start reporting; by definition, all F=0 in this year
 
 ; Optional radiative forcing constraint
 ;RF_tot_constrain=csv:tables/CONSTRAINT.csv
+aero_scalar=1.0     		; uncertainty scaling factor for aerosol forcing
+vol_scalar=1.0    		; uncertainty scaling factor for volcanic forcing
 delta_co2=0.05		; (unitless) forcing tropospheric adjustments for CO2 (7.3.2.1 of IPCC AR6)
 delta_ch4=-.14		; (unitless) forcing tropospheric adjustments for CH4 (7.3.2.2 of IPCC AR6)
 delta_n2o=0.07		; (unitless) forcing tropospheric adjustments for N2O (7.3.2.3 of IPCC AR6)
@@ -179,8 +181,6 @@ RF_misc[1750]=0
 [temperature]
 S=3.0 			; equilibrium climate sensitivity for 2xCO2 degC (A.4.4 of IPCC AR6)
 diff=2.38		; ocean heat diffusivity, cm2/s calibrated to historical observations Dorheim et al. 2024 for details
-alpha=1.0     	; uncertainty scaling factor for aerosol forcing
-volscl=1.0    	; uncertainty scaling factor for volcanic forcing
 qco2=3.75     	; 2×CO2 RF (7.3.2 of IPCC AR6)
 
 ; Optional global temperature constraint

inst/input/hector_ssp585.ini

@@ -162,6 +162,8 @@ baseyear=1750		; when to start reporting; by definition, all F=0 in this year
 
 ; Optional radiative forcing constraint
 ;RF_tot_constrain=csv:tables/CONSTRAINT.csv
+aero_scalar=1.0     		; uncertainty scaling factor for aerosol forcing
+vol_scalar=1.0    		; uncertainty scaling factor for volcanic forcing
 delta_co2=0.05		; (unitless) forcing tropospheric adjustments for CO2 (7.3.2.1 of IPCC AR6)
 delta_ch4=-.14		; (unitless) forcing tropospheric adjustments for CH4 (7.3.2.2 of IPCC AR6)
 delta_n2o=0.07		; (unitless) forcing tropospheric adjustments for N2O (7.3.2.3 of IPCC AR6)
@@ -179,8 +181,6 @@ RF_misc[1750]=0
 [temperature]
 S=3.0 			; equilibrium climate sensitivity for 2xCO2 degC (A.4.4 of IPCC AR6)
 diff=2.38		; ocean heat diffusivity, cm2/s calibrated to historical observations Dorheim et al. 2024 for details
-alpha=1.0     	; uncertainty scaling factor for aerosol forcing
-volscl=1.0    	; uncertainty scaling factor for volcanic forcing
 qco2=3.75     	; 2×CO2 RF (7.3.2 of IPCC AR6)
 
 ; Optional global temperature constraint

project_files/Xcode/hector.xcodeproj/project.pbxproj

@@ -82,9 +82,9 @@
 		27B2C270261511C8005DE26D /* spline_forsythe.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 27B2C24D261511C8005DE26D /* spline_forsythe.cpp */; };
 		27B2C271261511C8005DE26D /* main.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 27B2C24E261511C8005DE26D /* main.cpp */; };
 		27F2613726B55617004BDD47 /* csv_tracking_visitor.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 27962904268F237200333AA3 /* csv_tracking_visitor.cpp */; };
-		354045FC2913D50A00CA297D /* test_dependency_finder.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 273FC38F26A3570B00D5303E /* test_dependency_finder.cpp */; };
-		354045FB2913CF6600CA297D /* test_csv_file_reader.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 273FC39126A3570B00D5303E /* test_csv_file_reader.cpp */; };
 		354045FA2913C0F300CA297D /* test_core.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 273FC38D26A3570B00D5303E /* test_core.cpp */; };
+		354045FB2913CF6600CA297D /* test_csv_file_reader.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 273FC39126A3570B00D5303E /* test_csv_file_reader.cpp */; };
+		354045FC2913D50A00CA297D /* test_dependency_finder.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 273FC38F26A3570B00D5303E /* test_dependency_finder.cpp */; };
 		35ACB833285E4F4E0025928F /* h_util.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 275CBFF127AC7CC0009E2AF5 /* h_util.cpp */; };
 		954D62AE278E005500840656 /* nh3_component.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 954D62AD278E005500840656 /* nh3_component.cpp */; };
 		954D62AF278E005500840656 /* nh3_component.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 954D62AD278E005500840656 /* nh3_component.cpp */; };
@@ -607,7 +607,7 @@
 				GCC_WARN_UNINITIALIZED_AUTOS = YES_AGGRESSIVE;
 				GCC_WARN_UNUSED_FUNCTION = YES;
 				GCC_WARN_UNUSED_VARIABLE = YES;
-				HEADER_SEARCH_PATHS = "${BOOSTROOT}";
+				HEADER_SEARCH_PATHS = "${BOOSTINC}";
 				"HEADER_SEARCH_PATHS[arch=*]" = "${BOOSTROOT}";
 				LIBRARY_SEARCH_PATHS = "${BOOSTLIB}";
 				MACOSX_DEPLOYMENT_TARGET = 10.15;
@@ -664,7 +664,7 @@
 				GCC_WARN_UNINITIALIZED_AUTOS = YES_AGGRESSIVE;
 				GCC_WARN_UNUSED_FUNCTION = YES;
 				GCC_WARN_UNUSED_VARIABLE = YES;
-				HEADER_SEARCH_PATHS = "${BOOSTROOT}";
+				HEADER_SEARCH_PATHS = "${BOOSTINC}";
 				LIBRARY_SEARCH_PATHS = "${BOOSTLIB}";
 				MACOSX_DEPLOYMENT_TARGET = 10.15;
 				MTL_ENABLE_DEBUG_INFO = NO;
@@ -681,6 +681,7 @@
 			buildSettings = {
 				CODE_SIGN_IDENTITY = "-";
 				CODE_SIGN_STYLE = Automatic;
+				HEADER_SEARCH_PATHS = "${BOOSTINC}";
 				LIBRARY_SEARCH_PATHS = "${BOOSTLIB}";
 				"OTHER_LDFLAGS[arch=*]" = "$(inherited)";
 				PRODUCT_NAME = "$(TARGET_NAME)";
@@ -692,6 +693,7 @@
 			buildSettings = {
 				CODE_SIGN_IDENTITY = "-";
 				CODE_SIGN_STYLE = Automatic;
+				HEADER_SEARCH_PATHS = "${BOOSTINC}";
 				LIBRARY_SEARCH_PATHS = "${BOOSTLIB}";
 				PRODUCT_NAME = "$(TARGET_NAME)";
 			};

src/forcing_component.cpp

@@ -132,6 +132,9 @@ void ForcingComponent::init(Core *coreptr) {
   core->registerCapability(D_RHO_SO2, getComponentName());
   core->registerCapability(D_RF_SO2, getComponentName());
   core->registerCapability(D_RF_ACI, getComponentName());
+  core->registerCapability(D_AERO_SCALE, getComponentName());
+  core->registerCapability(D_VOLCANIC_SCALE, getComponentName());
+
   for (int i = 0; i < N_HALO_FORCINGS; ++i) {
     core->registerCapability(adjusted_halo_forcings[i], getComponentName());
     forcing_name_map[adjusted_halo_forcings[i]] = halo_forcing_names[i];
@@ -183,6 +186,9 @@ void ForcingComponent::init(Core *coreptr) {
   core->registerInput(D_RHO_NH3, getComponentName());
   core->registerInput(D_RF_MISC, getComponentName());
   core->registerInput(D_FTOT_CONSTRAIN, getComponentName());
+  core->registerInput(D_AERO_SCALE, getComponentName());
+  core->registerInput(D_VOLCANIC_SCALE, getComponentName());
+
 }
 
 //------------------------------------------------------------------------------
@@ -237,6 +243,12 @@ void ForcingComponent::setData(const string &varName,
     } else if (varName == D_RHO_SO2) {
       H_ASSERT(data.date == Core::undefinedIndex(), "date not allowed");
       rho_so2 = data.getUnitval(U_W_M2_GG);
+    } else if (varName == D_AERO_SCALE) {
+      H_ASSERT(data.date == Core::undefinedIndex(), "date not allowed");
+      alpha = data.getUnitval(U_UNITLESS);
+    } else if (varName == D_VOLCANIC_SCALE) {
+      H_ASSERT(data.date == Core::undefinedIndex(), "date not allowed");
+      volscl = data.getUnitval(U_UNITLESS);
     } else if (varName == D_FTOT_CONSTRAIN) {
       H_ASSERT(data.date != Core::undefinedIndex(), "date required");
       Ftot_constrain.set(data.date, data.getUnitval(U_W_M2));
@@ -422,35 +434,37 @@ void ForcingComponent::run(const double runToDate) {
       double E_BC =
           core->sendMessage(M_GETDATA, D_EMISSIONS_BC, message_data(runToDate))
               .value(U_TG);
-      double fbc = rho_bc * E_BC;
+      double fbc = alpha.value(U_UNITLESS) * rho_bc * E_BC;
       forcings[D_RF_BC].set(fbc, U_W_M2);
 
       // ---------- Organic carbon ----------
       double E_OC =
           core->sendMessage(M_GETDATA, D_EMISSIONS_OC, message_data(runToDate))
               .value(U_TG);
-      double foc = rho_oc * E_OC;
+        double foc = alpha.value(U_UNITLESS) * rho_oc * E_OC;
       forcings[D_RF_OC].set(foc, U_W_M2);
 
       // ---------- Sulphate Aerosols ----------
       unitval SO2_emission = core->sendMessage(M_GETDATA, D_EMISSIONS_SO2,
                                                message_data(runToDate));
-      double fso2 = rho_so2 * SO2_emission.value(U_GG_S);
+      double fso2 = alpha.value(U_UNITLESS) * rho_so2 * SO2_emission.value(U_GG_S);
       forcings[D_RF_SO2].set(fso2, U_W_M2);
 
       // ---------- NH3 ----------
       double E_NH3 =
           core->sendMessage(M_GETDATA, D_EMISSIONS_NH3, message_data(runToDate))
               .value(U_TG);
-      double fnh3 = rho_nh3 * E_NH3;
+      double fnh3 = alpha.value(U_UNITLESS) * rho_nh3 * E_NH3;
       forcings[D_RF_NH3].set(fnh3, U_W_M2);
 
       // ---------- RFaci ----------
       // ERF from aerosol-cloud interactions (RFaci)
       // Based on Equation 7.SM.1.2 from IPCC AR6 where
-      double aci_rf =
-          -1 * aci_beta *
-          log(1 + (SO2_emission / s_SO2) + ((E_BC + E_OC) / s_BCOC));
+      // The 0.2 value comes from equally distributing the alpha scalar to all 5
+      // aerosol RF types.
+        double aci_rf =
+            alpha.value(U_UNITLESS) * (-1 * aci_beta *
+            log(1 + (SO2_emission / s_SO2) + ((E_BC + E_OC) / s_BCOC)));
       forcings[D_RF_ACI].set(aci_rf, U_W_M2);
     }
 
@@ -464,6 +478,7 @@ void ForcingComponent::run(const double runToDate) {
     if (core->checkCapability(D_VOLCANIC_SO2)) {
       // The volcanic forcings are read in from an ini file.
       forcings[D_RF_VOL] =
+          volscl.value(U_UNITLESS) *
           core->sendMessage(M_GETDATA, D_VOLCANIC_SO2, message_data(runToDate));
     }
 
@@ -540,6 +555,10 @@ unitval ForcingComponent::getData(const std::string &varName,
     returnval = rho_so2;
   } else if (varName == D_RHO_NH3) {
     returnval = rho_nh3;
+  } else if (varName == D_AERO_SCALE) {
+    returnval = alpha;
+  } else if (varName == D_VOLCANIC_SCALE) {
+    returnval = volscl;
   } else if (varName == D_RF_BASEYEAR) {
     returnval.set(baseyear, U_UNITLESS);
   } else {