I have read some where also the increase tmps can also indirectly kill corals by magnifying the effects of infectious diseases, which are one of the primary causes of coral loss, during the summer time. The severity of marine diseases could increase with temperature for several reasons. Because elevated water temperature causes corals physiological stress, it can also compromise their immune system, potentially making them more susceptible to infections. Additionally, increased temperature could also benefit bacterial and fungal pathogens, making them more fit and/or virulent. hth