diff --git a/config/model_configs/gpu_aquaplanet_dyamond.yml b/config/model_configs/gpu_aquaplanet_dyamond.yml
index 50c4a508696..c4e0430a780 100644
--- a/config/model_configs/gpu_aquaplanet_dyamond.yml
+++ b/config/model_configs/gpu_aquaplanet_dyamond.yml
@@ -18,5 +18,6 @@ surface_setup: "DefaultMoninObukhov"
 rayleigh_sponge: true
 dt: "100secs"
 t_end: "8hours"
+aerosol_radiation: true
 prescribed_aerosols: ["CB1", "CB2", "DST01", "DST02", "DST03", "DST04", "OC1", "OC2", "SO4", "SOA", "SSLT01", "SSLT02", "SSLT03", "SSLT04"]
 toml: [toml/longrun_aquaplanet_dyamond.toml]
diff --git a/src/callbacks/callbacks.jl b/src/callbacks/callbacks.jl
index 1da95fe6b20..333a284f92d 100644
--- a/src/callbacks/callbacks.jl
+++ b/src/callbacks/callbacks.jl
@@ -262,7 +262,11 @@ function set_aerosol_type(;
     OC2 = 0,
     _...,
 )
-    _, index = findmax((DST01, SSLT01, SO4, CB1, CB2, OC1, OC2))
+    maxval = max(DST01, SSLT01, SO4, CB1, CB2, OC1, OC2)
+    index = findfirst(
+        c -> c == maxval,
+        (DST01, SSLT01, SO4, CB1, CB2, OC1, OC2),
+    )::Int
     return index
 end
 set_aerosol_type(NT) = set_aerosol_type(; NT...)