The impact of climate change is being felt by millions of people who have endured intense storm activity, record heat, and persistent droughts. The buildup of carbon dioxide concentrations in the atmosphere due to the burning of fossil fuels is also having a negative effect on the ocean. In fact, the implications of this aspect of climate change may be the most serious of all.
Over one-third of carbon dioxide released is entering the ocean. Some of this is reacting with water to form carbonic acid. A series of chemical reactions can result in a decrease of the ocean’s pH or an increase in its acidity. Ocean acidification is a corrosive process causing a decline in the availability of compounds needed by a wide variety of marine species. Some scientists have estimated that human activity has increased the ocean acidity by thirty percent, and that this is the most acidic ocean in millions of years.
These figures have marine scientists worried about their long-term impact on the food web, particularly in sensitive areas such as coral reefs. Coral animals, as well as some zooplankton, mollusks, sea stars, sea urchins and crabs, depend on the availability of calcium carbonate to form their shells. Coral reefs support large numbers of invertebrates and fish which feed millions of people. These reefs are threatened by warmer temperatures. The coral animals lose their symbiotic algae which provide sugars and color and turn white, hence the term “bleaching.” Many coral reefs are lost each year.
There are dire predictions for the shellfish populations as well. There is evidence that oyster larvae in the Pacific northwest have been killed by acidic marine waters. The larval stages of mollusks and echinoderms are sensitive to changes in water chemistry. These stages are also part of the important plankton at the base of the food web. Fish populations will dramatically decrease if their food source declines.
We have known for some time how to slow down this process. Unfortunately, the political system has failed to implement policies that address the problem. There is a political paralysis in place which is resulting in record economic and environmental losses. We need to sharply reduce the use of fossil fuels. Instead of promoting oil pipelines, natural gas fracking, or “clean coal” technology, our efforts should promote the widespread use of solar, wind, and other renewable, nonpolluting energy sources. Climate change could very well be the most significant problem we have ever faced.
Copyright Gil Newton 2009 Thanks to Chris Dumas for logo image.