The Great Barrier Reef is almost certainly doomed. But that's OK, because our own doom is only probable, not certain. It will die before we do. It will die because of us. But we are such a resourceful, inventive, endlessly self-seeking species that we might yet survive the catastrophe we have visited upon the planet. Maybe in domes.
Yes, huge city-sized domes with a Soylent Green stall on every corner. That would be cool.