remove contribution for ice-free ocean in diagnostics of surface temperature  changes (small anyway, and only there when using slab-ocean)
remove contribution for ice-free ocean in diagnostics of surface temperature
 changes (small anyway, and only there when using slab-ocean)

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