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Fukushima radiation scare in Pacific pales compared to acidification

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By Bob McDonald, Quirks & Quarks


A plume of radioactive contamination from the damaged Fukushima Nuclear plant in Japan has reached the coast of North America earlier than expected. But while concerns for the plume are making headlines, a far more serious effect of human activity is already having dire consequences for West Coast fisheries.

Last August, about 250 tonnes of contaminated water - that had been sprayed onto the damaged reactors to keep them cool - leaked out of storage tanks into the ocean. This added to the contamination from the original disaster, when the plant was damaged by a tsunami in 2011, and from ground water that has flowed through the site since. 

The amount of radioactive material released into the ocean is unprecedented. Now, that plume has been carried by ocean currents across the Pacific to North American shores. 

But thanks to the immense size of the Pacific, radiation levels measured so far on this side of the ocean are extremely low trace amounts - well within safety guidelines for drinking water. Those levels are not expected to rise significantly, because of the dilution effect of the plume crossing thousands of kilometers of open ocean. 

This is not to say the problem has been solved; the ocean is just giving us some time while the source of contamination is fixed.

As part of the monitoring of the contamination, as well as an effort to reassure the public, the Woods Hole Oceanographic Institute is offering testing kits to people living along the west coast of the U.S. and Canada so they can test the water themselves. Samples of seawater taken while strolling on beaches can be sent back to Woods Hole for analysis. 

The kits are not cheap, at $600 U.S. each, so it is suggested that the project should be crowd-sourced through a community of volunteers. This is a good way to do research over a wide area through "citizen science" during these times of funding cutbacks.

But while testing the ocean for radiation levels is important, there is another invisible contaminant in the water that is being overlooked and which is already doing much more harm to the fisheries: ocean acidification.

Since the industrial revolution, about one-third of the carbon dioxide produced by burning fossil fuels has been absorbed by the oceans, making the water more acidic. 

When carbon dioxide is absorbed, it reacts with sea water to produce carbonic acid.  If you remember back to high school chemistry class, acids and bases are opposites and will react with each other. Sea shells and corals are made of calcium carbonate, which is basic. As the oceans become more acidic, coral reefs, oysters, clams, scallops, sea urchins, and even some plankton suffer.

This was reported this week by fishers in B.C. who are seeing yet another season of dramatic declines in the number of scallops, as well as a lower quality to their shells. In acidic waters, shells grow thinner, providing less protection for the animals against predators. It also lowers the immune systems, so more are killed off by disease.

These effects of ocean acidification and rising seawater temperatures due to climate change are showing up in all parts of the globe. Half of the Earth's coral reefs have been bleached out because the algae that live in symbiosis with the corals, and give it its colour, cannot tolerate the changing conditions.

These ocean creatures that are affected by acidification are at the bottom of the food chain, so we are eroding the very foundation of life in the sea during a time when we are depending more and more on the oceans as a source of food.  

Ocean acidification is an invisible menace that threatens the entire ecosystem and it's only getting worse. Carbon emissions worldwide, and especially in Canada, continue to rise.

Without diminishing the significance of several hundred tonnes of radioactive water released from Fukushima into the ocean, its effect on sea life is dwarfed by the billions of tonnes of carbon dioxide being absorbed by sea water every day.

It's ironic that people will pay to test ocean water, to be reassured that they will not be poisoned from almost non-existent radiation, yet they'll not consider the impact of their much more damaging fossil-fuel-burning vehicles that they drove to the beach to do the test.