I don't know about all the world's coral (I don't see how anybody can), but the Great Barrier Reef now has the highest level of coral cover since records began in 1986, which even the BBC were forced to admit. https://electroverse.co/great-barrier-reef-sees-record-coral-cover/ https://www.bbc.co.uk/news/world-australia-62402891 It's another climate alarmism poster child that is not fit for purpose!