julia> show(err)
1-element ExceptionStack:
Scalar indexing is disallowed.
Invocation of getindex resulted in scalar indexing of a GPU array.
This is typically caused by calling an iterating implementation of a method.
Such implementations *do not* execute on the GPU, but very slowly on the CPU,
and therefore should be avoided.

If you want to allow scalar iteration, use `allowscalar` or `@allowscalar`
to enable scalar iteration globally or for the operations in question.        
Stacktrace:
  [1] error(s::String)
    @ Base ./error.jl:35
  [2] errorscalar(op::String)
    @ GPUArraysCore ~/.julia/packages/GPUArraysCore/GMsgk/src/GPUArraysCore.jl:155
  [3] _assertscalar(op::String, behavior::GPUArraysCore.ScalarIndexing)
    @ GPUArraysCore ~/.julia/packages/GPUArraysCore/GMsgk/src/GPUArraysCore.jl:128
  [4] assertscalar(op::String)
    @ GPUArraysCore ~/.julia/packages/GPUArraysCore/GMsgk/src/GPUArraysCore.jl:116
  [5] getindex(A::CUDA.CuArray{Float32, 5, CUDA.Mem.DeviceBuffer}, I::Int64)
    @ GPUArrays ~/.julia/packages/GPUArrays/OqrUV/src/host/indexing.jl:48
  [6] scalar_getindex(::CUDA.CuArray{Float32, 5, CUDA.Mem.DeviceBuffer}, ::Int64, ::Vararg{Int64})
    @ GPUArrays ~/.julia/packages/GPUArrays/OqrUV/src/host/indexing.jl:34
  [7] _getindex
    @ ~/.julia/packages/GPUArrays/OqrUV/src/host/indexing.jl:17 [inlined]
  [8] getindex
    @ ~/.julia/packages/GPUArrays/OqrUV/src/host/indexing.jl:15 [inlined]
  [9] getindex
    @ ./subarray.jl:290 [inlined]
 [10] _getindex
    @ ./abstractarray.jl:1341 [inlined]
 [11] getindex
    @ ./abstractarray.jl:1291 [inlined]
 [12] get_struct
    @ ~/CliMA/ClimaCore.jl/src/DataLayouts/struct.jl:218 [inlined]
 [13] macro expansion
    @ ~/CliMA/ClimaCore.jl/src/DataLayouts/struct.jl:200 [inlined]
 [14] macro expansion
    @ ./none:0 [inlined]
 [15] get_struct
    @ ./none:0 [inlined]
 [16] getindex
    @ ~/CliMA/ClimaCore.jl/src/DataLayouts/DataLayouts.jl:1026 [inlined]
 [17] getindex
    @ ~/CliMA/ClimaCore.jl/src/DataLayouts/DataLayouts.jl:1033 [inlined]
 [18] _broadcast_getindex
    @ ./broadcast.jl:662 [inlined]
 [19] _getindex
    @ ./broadcast.jl:706 [inlined]
 [20] _getindex
    @ ./broadcast.jl:705 [inlined]
 [21] _broadcast_getindex
    @ ./broadcast.jl:681 [inlined]
 [22] getindex
    @ ./broadcast.jl:636 [inlined]
 [23] copyto!(dest::ClimaCore.DataLayouts.VF{Float32, 70, SubArray{Float32, 2, Base.ReshapedArray{Float32, 5, SubArray{Float32, 2, CUDA.CuArray{Float32, 2, CUDA.Mem.DeviceBuffer}, Tuple{UnitRange{Int64}, Base.Slice{Base.OneTo{Int64}}}, false}, Tuple{Base.MultiplicativeInverses.SignedMultiplicativeInverse{Int64}}}, Tuple{Base.Slice{Base.OneTo{Int64}}, Int64, Int64, Base.Slice{Base.OneTo{Int64}}, Int64}, false}}, bc::Base.Broadcast.Broadcasted{ClimaCore.DataLayouts.VFStyle{70, CUDA.CuArray{Float32, N, CUDA.Mem.DeviceBuffer} where N}, Nothing, typeof(Thermodynamics.air_pressure), Tuple{Tuple{Thermodynamics.Parameters.ThermodynamicsParameters{Float32}}, ClimaCore.DataLayouts.VF{Thermodynamics.PhaseDry{Float32}, 70, SubArray{Float32, 2, CUDA.CuArray{Float32, 5, CUDA.Mem.DeviceBuffer}, Tuple{Base.Slice{Base.OneTo{Int64}}, Int64, Int64, Base.Slice{Base.OneTo{Int64}}, Int64}, false}}}})
    @ ClimaCore.DataLayouts ~/CliMA/ClimaCore.jl/src/DataLayouts/broadcast.jl:576
 [24] copyto!(dest::ClimaCore.DataLayouts.VIJFH{Float32, 70, 1, Base.ReshapedArray{Float32, 5, SubArray{Float32, 2, CUDA.CuArray{Float32, 2, CUDA.Mem.DeviceBuffer}, Tuple{UnitRange{Int64}, Base.Slice{Base.OneTo{Int64}}}, false}, Tuple{Base.MultiplicativeInverses.SignedMultiplicativeInverse{Int64}}}}, bc::Base.Broadcast.Broadcasted{ClimaCore.DataLayouts.VIJFHStyle{70, 1, CUDA.CuArray{Float32, N, CUDA.Mem.DeviceBuffer} where N}, NTuple{5, Base.OneTo{Int64}}, typeof(Thermodynamics.air_pressure), Tuple{Tuple{Thermodynamics.Parameters.ThermodynamicsParameters{Float32}}, ClimaCore.DataLayouts.VIJFH{Thermodynamics.PhaseDry{Float32}, 70, 1, CUDA.CuArray{Float32, 5, CUDA.Mem.DeviceBuffer}}}})
    @ ClimaCore.DataLayouts ~/CliMA/ClimaCore.jl/src/DataLayouts/broadcast.jl:604
 [25] copyto!
    @ ~/CliMA/ClimaCore.jl/src/Fields/broadcast.jl:149 [inlined]