E-Mail Five world-renowned scientists have signed a letter to UNESCO Director-General Audrey Azoulay to "thank UNESCO for its leadership in recognising the threat of climate change to the Great Barrier Reef World Heritage property." Professor Terry Hughes, Professor Ove Hoegh-Guldberg, Dr Sylvia Earle, Professor Johan Rockström and Professor Andréa Grottoli sent the letter last night from Australia. Last month, UNESCO released a draft decision recommending the Great Barrier Reef be inscribed on the List of World Heritage in Danger. The scientists' letter is a strong show of support for UNESCO from some of the most revered coral reef experts in the world.