NewScientist (17 October 2015, paywall) reports on the impact of the current monster El Niño on corals around the world:
So far coral bleaching has been seen around the Solomon Islands in the South Pacific, around Hawaii in the North Pacific and around the Maldives in the Indian Ocean. This distribution was the trigger for the announcement by the US National Oceanic and Atmospheric Administration (NOAA) that we are seeing the third ever global coral bleaching event. These observations confirmed predictions made by NOAA, giving the agency confidence in its forecast of a much bigger global bleaching event brought about by El Niño.
Which reefs are under threat next?
According to NOAA’s four-month projection, coral bleaching will affect 38 per cent of the world’s coral reefs by the end of the year. That includes everywhere from the Great Barrier Reef in Australia to reefs in the Caribbean and the Indian Ocean.
Remember, bleaching is not the same as dying. As noted in earlier in this thread, previous research had used poor proxies for understanding how coral reacts, and, even more importantly, coral can recover, or be replaced, fairly quickly.