Social Issues May 26, 2012
Our Oceans At Risk: A Conversation With Marine Biologist Peter Sale

Last week, marine biologist Callum Roberts released a book called 'The Ocean of Life', about his belief that our oceans and seas are at risk.

Canadian professor Peter Sale, author of 'Our Dying Planet: An Ecologist's View of the Crisis We Face', has also weighed in on the situation: "I do not think we yet have a full grasp of the extent of the damage we are causing to ocean ecology, but the fact that we can talk about something as profound as the total disappearance of coral reefs from the planet by 2050 suggests the changes are damned serious".

We got Professor Sale on the phone to dig a little deeper into the issues we're facing. Here are some of his thoughts on what's going on with our bodies of water:

Coral Reefs: Canaries In The Coalmine

The risk to coral reefs is so great that, Professor Sale suggests, they could disappear entirely in the next 30-40 years. Why are coral reefs so vulnerable? He explains that "coral have quite narrow requirements for their reproductive systems", which makes them particularly susceptible to slight shifts in the pH levels of water.

The professor says climate change is causing major shifts in the pH level of shallower waters where coral lives. The delicate nature of coral means "they can't tolerate much in the way of fluctuation" and "they're very dependent on high-quality water" - meaning even minor changes in the pH balance of the water they live in can be dangerous.

The skeletal structure of a coral reef is built through a process of calcium carbonification, and professor Sale says "some of them, at least, are going to be compromised by changes in the ocean's pH, making it more difficult to develop" those skeletons. And the main reason for that difficulty is ocean acidification, which Professor Sale calls "one of the most serious issues" facing our oceans.

Acid Test: Ocean Acidification And The Damage To Marine Life

Professor Sale says that "the changes in the ocean's pH are happening at the surface layer. The deep water ocean isn't getting more acidic." But while the news that deep water isn't affected may seem like a positive thing, it is causing problems for the marine ecosystem as the surface water profoundly changes.

The professor says the change could end up so drastic that the water at the surface is as different from the deep water as oil is from water. As he puts it, "oil and water don't mix very well [and] it's a little bit like that, we're creating a situation where the surface water is changing very rapidly".

The effects on marine life are already clear, the professor says: researchers have seen "failures of oysters on the West coast", and "studies showing the behavior of fish has changed" so that they "don't provide the young fish for the next generation". As the differences between surface and deep water become more pronounced, it will throw off the balance of the ecosystem, potentially leading to problems for many other species.

Looking Forward: Can We Wait A Thousand Years?

When asked about whether the ocean will ever return to the state it was in prior to the current phase of environmental damage, Professor Sale had a somewhat surprising answer: "it'll come back, even if we keep doing what we're doing". But here's the catch: the ocean is resilient enough to absorb the damage, but it will take over a thousand years to return to its original state.

If we don't want to wait a millennium for the oceans to restore themselves, the professor says we need to make changes now by reducing the amount of CO2 we're pumping into the atmosphere. In the short term, "the lower we move our CO2 emissions, the better off we'll be". Reducing emissions "will have an immediate effect" according to Professor Sale.

He suggests that the severity of the damage that's occurring in our oceans is a result of the volume of pollutants that we're releasing: "If we were dumping CO2 into the atmosphere slowly, we wouldn't be having any trouble".

What Does This Mean For Humanity?

Polluted oceans are a danger to the creatures that live in the water, but they can also have a profound effect on the human population. For one thing, damaging marine ecosystems could seriously damage our food supplies.

Professor Sale points out that worldwide, "16 percent of the animal protein for people comes from the ocean", in the form of the seafood that we fish and eat. If we lose some or all of that protein, Professor Sale says "it's not like we've got abundant stores of food resources that we're not tapping". It could lead to hunger in many parts of the world.

Guessing At The Future

Professor Sale admits that no one knows exactly what will happen with the ocean - "the story of the ocean is in progress. We don't know what the future holds, but we can make an educated guess". But he says one thing is clear: "We can certainly make the ocean much more productive, much more connected, much more valuable to us by making some changes".

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