When we burn coal, oil, or gas, the resulting carbon dioxide is
released into the atmosphere where it acts as a greenhouse gas. Greenhouse gases emitted by human activity don't just affect the atmosphere; they also have a negative impact on the world's oceans. Coral reefs are particularly vulnerable to the ocean acidification process, because reef architecture is built by the accretion of calcium carbonate, called calcification, which becomes increasingly difficult as acid concentrations increase and the surrounding water's pH decreases.
Scientists predict that reefs could switch from carbonate accretion to dissolution within the century due to this acidification process."Our work provides the first strong evidence from experiments on a natural ecosystem that ocean acidification is already slowing coral reef growth," Albright said. "Ocean acidification is already taking its toll on coral reef communities. This is no longer a fear for the future; it is the reality of today." Source: Carnegie Institution www.sciencedaily.com
Corals are tiny animals that live in colonies and derive nourishment and energy from a symbiotic relationship with zooxanthellae algae. Coral reefs are formed over the course of thousands of years as limestone skeletons constructed by corals accumulate and form a structural base for living corals. Scientists estimate reefs provide a home for millions of species - from brightly colored tropical fish to sea cucumbers which produce anti-cancer compounds. Like tropical rainforests, coral reefs are imperilled by human influences. 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. In 1998, when tropical sea surface temperatures were the highest in recorded history, coral reefs around the world suffered the most severe bleaching on record. 2002 was even worse: nearly 60% of the 135,000 square mile Great Barrier Reef suffered some bleaching. It is estimated that even under the best of conditions, many of these coral reef ecosystems will need decades to recover. Although reefs face other threats from pollution, industrial activities, overfishing, siltation, cyanide and dynamite fishing, and anchors, it is global climate change that most concerns scientists. RECENT ARTICLES
Coral reefs decimated by 2050, Great Barrier Reef's coral 95% dead November 17, 2005 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. The startling and controversial prediction, made last year in a report commissioned by the World Worldwide Fund for Nature (WWF) and the Queensland government, is just one of the dire scenarios forecast for reefs in the near future. The degradation and possible disappearance of these ecosystems would have profound socioeconomic ramifications as well as ecological impacts