The 1200 mile Great Barrier Reef, is in great danger of near elimination. The warming of ocean waters is expected to kill 95 percent of the reef within fifty years.
Scientists have positively linked warmer waters to the bleaching and death of ocean corals. While changes as small as one degree Celsius can cause serious damage, temperatures are expected to rise two to six degrees in the next century.
With the reef providing huge tourism benefits to Australia every year, the study predicts a loss of as many as 12,000 jobs as soon as the year 2020. Source