diff --git a/src/callbacks/callbacks.jl b/src/callbacks/callbacks.jl
index 5ace4bbd53a..5ec29cc8eaf 100644
--- a/src/callbacks/callbacks.jl
+++ b/src/callbacks/callbacks.jl
@@ -262,11 +262,7 @@ function set_aerosol_type(;
     OC2 = 0,
     _...,
 )
-    maxval = max(DST01, SSLT01, SO4, CB1, CB2, OC1, OC2)
-    index = findfirst(
-        c -> c == maxval,
-        (DST01, SSLT01, SO4, CB1, CB2, OC1, OC2),
-    )
+    _, index = findmax((DST01, SSLT01, SO4, CB1, CB2, OC1, OC2))::Tuple{Float32, Int}
     return index
 end
 set_aerosol_type(NT) = set_aerosol_type(; NT...)