Global climate change is leading to the rise of ocean temperatures and is triggering mass coral bleaching events on reefs around the world. The expulsion of the symbiotic dinoflagellate algae from the coral host is believed to occur as a result of damage to the photosynthetic apparatus of these symbionts, although the specific site of initial impact has not been identified. This book provides evidence of impacts to a number of sites within the light reactions of photosynthesis and evaluates the efficiency of photoprotective heat dissipating pathways. Specifically, the oxygen evolving complex, the Photosystem II reaction centre and the thylakoid membrane, are examined to evaluate thermal sensitivity. The capacity for symbionts to survive in the water column once expelled from the host is also explored. This book should be useful to students and professionals working on climate change impacts to coral reefs, as well as those interested in developing skills on coral health assessment.