rewrite for better vectorization, changes global_ocean.cs32x15/input.icedyn (11 digits of agreement)
rewrite for better vectorization, changes global_ocean.cs32x15/input.icedyn (11 digits of agreement)

altMITgcm/MITgcm66h,altMITgcm/MITgcm66h,altMITgcm/MITgcm66h,altMITgcm/MITgcm66h,altMITgcm/MITgcm66h,altMITgcm/MITgcm66h,altMITgcm/MITgcm66h,altMITgcm/MITgcm66h