Diving deep into our ailing oceans
Much of the world’s oceans remain a mystery. But one thing we know for sure is that we can’t live without them. Find out how this crucial resource is under threat—and what you can do to help.
As a child, I lived on a remote island and spent a lot of time criss-crossing a windswept channel in a tiny ragtop speedboat, waves crashing all around and splashing me with ocean spray. Consequently, I grew up terrified of the ocean. But I had it exactly backwards. I had little to fear from the ocean. The ocean, on the other hand, had plenty to fear from me.
There are numerous threats to our oceans. So much so that in June 2017, representatives from nearly 200 countries felt impelled to collect at United Nations headquarters for a conference on oceans—the first of its kind—to chart a course away from catastrophe.
From that meeting came an urgent international call to protect and preserve the world’s oceans and habitats, for the sake of the planet as well as ourselves. As UN Secretary General Antonio Guterres put it in his speech to the assembly, “Conserving our oceans and using them sustainably is preserving life itself.”
He wasn’t wrong. Besides providing roughly half of the oxygen we breathe every minute of the day, the oceans also play a pivotal role in regulating the earth’s climate. Seafood from the oceans is also a crucial food source, providing 3.1 billion people with 20 percent of their annual protein, according to one estimate, and supporting the livelihoods of roughly 12 percent of the world’s population.
But everywhere you look, human activity is creating serious threats to our oceans. Below are a few of the biggest problem areas.
In recent years, microbeads—tiny bits of plastic found in exfoliating scrubs that wash down the sink and out into the marine environment—have been much in the news, and while their impact on the plastic content of the oceans has been significant, they’re only a relatively small part of the story.
Large and small plastics find their way into the ocean from a range of activities and products, from consumer packaging to car tires and fishing lines. According to a report by the World Economic Forum, if current trends persist, by 2050 there will be more plastic in the ocean than fish, if compared by weight.
And apparently all that plastic makes a tempting snack. At this point, plastic has been found in tens of thousands of marine organisms, in some cases contaminating up to 80 percent of a sampled species.
This is a potentially significant problem for marine wildlife and, ultimately, for us. Ocean plastics can act as a carrier for chemicals and organic contaminants, from PCBs to DDT, and reports have shown that ingestion of plastics can have a wide range of harmful effects on marine organisms—changing energy levels, growth, breeding success, and other behaviours, as well as creating potentially harmful levels of particle toxicity.
What this means for human well-being isn’t yet entirely clear, and experts are careful to emphasize they don’t want people to forgo eating nutritious seafood. But with ocean plastic levels increasing every day, there is reason to worry about the long-term trends regarding food security and human health.
Another one of the threats to our oceans, not to mention the world climate as a whole, is ocean acidification. One of the ocean’s major functions is to draw carbon dioxide, CO2, from the atmosphere. Each year it gobbles up 30 percent of the world’s CO2, helping to protect the world from climate change.
Unfortunately, that process also increases ocean acidification, which disrupts species’ growth and reproduction, contributes to the erosion of the coral reefs, and—this is key—reduces the ocean’s ability to absorb CO2.
The only solution to this problem is to reduce our carbon emissions. If we don’t, the result will be drastically altered marine ecosystems, dead coral, and a much warmer world.
We’ve already seen how important the fisheries are to global food and employment. It’s no surprise, then, that fish stocks are under relentless pressure from overfishing, despite gains in many areas in recent years.
According to a recent report by the Food and Agriculture Organization for the United Nations, almost 90 percent of the world’s fish stocks are either overfished or fished to capacity. Of those, 31.4 percent are overfished, meaning that they are fished at a biologically unsustainable level.
Sewage outfalls. Agricultural runoff. Oil spills. Coal smoke. Pollution enters our oceans from a multitude of sources, and the results can be extremely harmful for animal and human health.
Perhaps the most worrisome is agricultural runoff—especially from nitrogen fertilizers—which, along with other pollutants, contributes to the formation of massive hypoxic dead zones in the ocean.
Another particularly concerning contaminant is the neurotoxin methyl mercury, which transfers to the ocean from sources such as coal plants and gold mines, then bioaccumulates in large marine animals that are then consumed by humans.
As our old school textbooks once told us, life on earth began in the sea, and today that ancient link to the oceans is no less vital to our place here. International summits such as the UN Ocean Conference notwithstanding, it is ultimately up to us as individuals to help reduce threats to our oceans and ensure that they remain thriving, clean, and healthy. That means our plastic wrappers, our spilled gasoline, our choices.
“It’s all of us or nothing,” said Peter Thomson, president of the UN General Assembly, as the Ocean Conference came to a close. “From this point onward nobody can say they are unaware.”