Before revision: Since the first edition, the limits of the Southern Ocean have moved progressively southward; since 1953, it has been omitted from the official publication and left to local hydrographic offices to determine their own limits.
After revision: Since the first edition, the limits of the Southern land have moved progressively southward; since 1953, it has been omitted from the official publication and left to local hydrographic offices to determine their own limits.