Jennifer Marohasy is speaking on Sunday in Maroochydore. Details at her blog.

Jen’s mother on Heron Island, mid 1950s.
From Jennifer Marohasy:
Corals usually grow-up to just below the lowest mean spring tide. Corals are particularly vulnerable to extremely low tides and in particular low tides in the middle of the day when there is also high solar radiation. The damage from such events may leave a characteristic tell-tale structure, for example, micro-atolls.
I have a picture of my mother (who migrated to Australia after WWII, see the picture featured at the top of this post) standing in front of a micro-atoll at Heron Island, where she worked as a waitress in the mid-1950s. I have another picture — I will show at the Maroochydore surf club on Sunday — showing the extent of the bleaching at Heron Island at that time.
This coral bleaching back in the 1950s, and much of the recent bleaching at the Great Barrier Reef, may have been due to falling sea levels, rather than extreme temperatures as I will explain on Sunday.
Everyone is welcome at the Surf Club. I will speak for about 1 hour … beginning at 2pm on Sunday 14th July on Level 3 which is the Conference Room, 36 Alexander Parade, Maroochydore.