Why is the Great Barrier Reef shrinking?

Australia's Great Barrier Reef could lose 95 percent of its living coral by 2050 should ocean temperatures increase by the 1.5 degrees Celsius projected by climate scientists.

While the Great Barrier Reef is one of the world's healthiest reefs, coral reefs are particularly fragile ecosystems, partly due to their sensitivity to water temperature. When corals are physiologically stressed -- as is the case when water temperatures are elevated -- they may lose much of the their symbiotic algae, an event known as "bleaching." Corals can recover from short-term bleaching, but prolonged bleaching can cause irreversible damage and subsequent death.