El-Nino and its impacts on coral reef ecosystem in 289the eastern Indian Ocean

The coral reef bleaching associated with the elevated Ocean temperature has been widely reported in the last three decades from different regions of the world. The rising temperature and acidification of Oceans makes a big challenge for the survival of reefs in the world. The other important stresses for the reefs include increased UV radiation, sea level variations, suspended sediments and increased turbidity of water. There are different studies which relate bleaching events with global warming and climate change. However, the increased frequency of mass bleaching events could not be sufficiently explained with current warming rates of the Ocean. Stone et al., (1999) put forward a new theory that recent increases in mass bleaching events were in response to the relative increase in El Nino experienced over the last two decades.