ALAMINOS CITY, Philippines — The country’s coral beds may be under water but they are not immune to the effects of global warming, a scientist who pioneered the study of corals in the Philippines has warned.
Dr. Edgardo Gomez, the founding director of the University of the Philippines Marine Science Institute, said the country’s corals were already under threat from bleaching and illegal fishing, but ocean “acidification” caused by excessive carbon dioxide in the atmosphere (which also causes global warming) has become a more “serious concern.”
“Carbon dioxide in the atmosphere eventually finds its way to and dissolves in the oceans, causing the water to become ‘acidic’… reducing the ability of the coral reefs to deposit calcium carbonate or calcify,” Gomez said.
This causes the calcium carbonate (which coral polyps use to build protective structures around them) to become weaker and susceptible to scratches and erosion.
According to Gomez, when this happens, predators, like the parrotfish, will have an easier time to eat the polyps and embedded algae in the coral.
Gomez is chair of the Southeast Asia/Philippines Center of Excellence of the Global Environment Facility and the World Bank Coral Reef Targeted Research and Capacity Building for Management Program. He was a guest during a recent conference here on coastal governance, where the status of coral reefs in the Lingayen Gulf and Zambales was discussed.
He said the corals would stop growing and eventually disintegrate in an ocean becoming more acidic.
The acidification of the ocean would affect not only corals but other sea shells and mollusks as well, he said.
The present pH level (measure of acidity) of oceans in the world has been slightly below 8.3, which is the normal level, according to Gomez. He said corals might start to dissolve if the pH level would drop below 8.
The problem is not yet manifest but at the rate the emission of greenhouse gases, particularly of carbon dioxide, is increasing in the atmosphere, acidification of the world’s oceans will be a big problem after 50 years, according to Gomez, who has been studying corals since 1976.
He said a number of scientific papers showed that there was a steep slope in the rate of increase of atmospheric carbon dioxide in the past several years.
“Two hundred years ago [at the start of the industrial revolution], the amount of carbon dioxide in the ocean was around 200 ppm (parts per million). Now it is nearly 400 ppm. If people continue their business as usual, the United Nations’ Intergovernmental Panel for Climate Change… predicts that it will be more than 500 ppm at the end of the century,” he said.
He said the acidification may be gradual but would happen simultaneously all over the world.
He said this would be worse than the acidification of agricultural lands due to the use of chemical fertilizers.
“Land is more manageable. With the use of organic fertilizer and chemicals, land can easily recover. But once the ocean becomes acidic, it would take millions of years to bring back their natural [state],” he said.
“The situation will get worse but it’s not too late to stave off disaster,” he said.
“The government should take concrete steps to reduce fossil fuel use and unnecessary production of greenhouse gases, stop deforestation, and switch to alternative sources of energy like geothermal, wind power, solar power, even nuclear power. Using hybrid cars will also help,” he said.
Gomez said a group of scientists, including himself, has been preparing a review of the problem for a scientific journal.
Yolanda Sotelo-Fuertes, Inquirer, 23 October 2007. Article.
Note from JPG: the pHs and pCO2 levels indicated in this article are incorrect. See, for example the EUR-OCEANS factsheet.
