fix: uninitialized variable usage

Author: aaraney

include/pet_tools.h

@@ -62,14 +62,14 @@ double calculate_net_radiation_W_per_sq_m(pet_model *model)
     surface_longwave_albedo=0.03;   // water - actually not this simple, but close enough for now
   }
 
-  if(model->pet_options.yes_aorc==0)  // we must calculate longwave incoming from the atmosphere 
+  if(model->pet_options.yes_aorc==0)
+  {
+    // calculate longwave incoming from the atmosphere
     saturation_water_vapor_partial_pressure_Pa=calc_air_saturation_vapor_pressure_Pa(model->surf_rad_forcing.air_temperature_C); 
 
-  actual_water_vapor_partial_pressure_Pa=model->surf_rad_forcing.relative_humidity_percent/100.0*
+    actual_water_vapor_partial_pressure_Pa=model->surf_rad_forcing.relative_humidity_percent/100.0*
                                          saturation_water_vapor_partial_pressure_Pa;
 
-  if(model->pet_options.yes_aorc==0)
-  {
     // CALCULATE DOWNWELLING LONGWAVE RADIATION FLUX FROM ATMOSPHERE, W/m2.
     if(0.90 < model->surf_rad_forcing.cloud_cover_fraction) // very nearly overcast or overcast
     {