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Tuesday, January 11, 2011

 Corals Reefs see Second Worst Year Ever in 2010
by Zachary Shahan
 

"Forecast stress on coral due to warm ocean temperatures for Australia, Jan - Apr 2011. The northern 2/3 of the Great Barrier Reef are under the highest alert level for coral bleaching. Waters are cooler along the southern portion of the reef, due, in part, to the storms that have brought record flooding to portions of Queensland, Australia."

We’ve covered coral bleaching, the devastation of coral reefs and their relationship to global warming here on Planetsave numerous times over the past few years. For clear reasons: this is a true global environmental catastrophe with numerous harmful ramifications. Dr Jeff Masters of WunderBlog delves into the harsh coral reef collapse of 2010 and future projections in a recent post. Here’s the intro:
Record warm ocean temperatures across much of Earth’s tropical oceans during the summer of 2010 created the second worst year globally for coral-killing bleaching episodes. The warm waters, fueled in part by the El Niño phenomena, caused the most coral bleaching since 1998, when 16 percent of the world’s reefs were killed off. “Clearly, we are on track for this to be the second worst (bleaching) on record,” NOAA coral expert Mark Eakin in an interview last month. “All we’re waiting on now is the body count.” The summer 2010 bleaching episodes were worst in Southeast Asia, where El Niño warming of the tropical ocean waters during the first half of the year was significant. In Indonesia’s Aceh province, 80% of the bleached corals died, and Malaysia closed several popular dive sites after nearly all the coral were damaged by bleaching. However, in the Caribbean’s Virgin Islands, coral bleaching was not as severe as experienced in 2005, according to National Park Service fisheries biologist Jeff Miller. I’ll discuss the reasons for this in a future blog post. In other portions of the Caribbean, such as Venezuela and Panama, coral bleaching was worse than that experienced in 2005.

"Departure of sea surface temperature in the Australian region over the past one hundred years, year-by-year (red line), and decade-by-decade (grey bars.) The 2010 value is preliminary and does not include data for December 2010. If ocean temperatures and ocean acidity continue to rise in Australian waters at the same pace as has occurred over the past 100 years, the Great Barrier Reef will be in significant danger by 2050."

And here’s the future outlook portion of the piece:
Long term outlook for world’s coral reefs: grim
The large amount of carbon dioxide humans have put into the air in recent decades has done more than just raise Earth’s global temperature–it has also increased the acidity of the oceans, since carbon dioxide dissolves in sea water to form carbonic acid. Corals have trouble growing in acidic sea water, and the combined effects of increasing ocean temperatures, increasing acidity, pollution, and overfishing have reduced coral reefs globally by 19 percent since 1950. Another 35 percent could disappear in the next 40 years, even without the impact of climate change, according to a report released in October 2010 by the World Meteorological Organization and the Convention on Biological Diversity. Coral loss has been the most severe in Earth’s hottest ocean, the Indian Ocean. Up to 90% of coral cover has been lost in the Maldives, Sri Lanka, Kenya and Tanzania and in the Seychelles. Global warming has heated up most of the tropical ocean surface waters by about 0.5°C (0.9°F) over the past 50 years, and the remarkable bleaching episodes of 1998 and 2010 both occurred when strong (natural) El Niño episodes heated up Pacific tropical waters to record levels. If the Earth continues to heat up this century as expected, coral bleaching episodes will grow more frequent and intense, particularly during strong El Niño episodes. The twin stresses of ocean acidification and increasing ocean temperatures will probably mean that by 2050, it will be difficult for any coral reefs to recover when subject to additional stresses posed by pollution or major storms, according to a talk presented by Stanford climate scientist Ken Caldeira at last month’s American Geophysical Union (AGU) meeting.

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