A big, somewhat odd suggestion.  It's starting to look as though much of the Great Barrier Reef north of Brisbane is doomed, but as things get warmer, one might develop, perhaps with a bit of encouragement, off Sydney.  In terms of latitude, that's like having a reef near Wilmington, North Carolina.  This article views it as protection against storms (no attention seems to be paid to surfing, which is sort of amazing)  Conversation.