We call it earth even though 75 percent of the planet is covered by water. And being so self-centered we think that what happens on land, where we live, is more important than what happens at sea. But once we account for the vastness of life existing at every depth of the seemingly bottomless oceans, we find that 99 percent of the planet’s biological environment is enveloped in water.  So, we ignore the ocean’s health at our peril.

We are slowly getting the message. Saskatchewan Agriculture tells us that a one inch rain falling on an acre brings 22,000 gallons to the land. That means that the six inch rain that fell July 1st on the six plus acres within Yorkton’s city limits brought down nearly one million gallons on residents – a small ocean. As the atmosphere warms from climate change, it holds even more moisture, and more moisture will be drawn up from the warming oceans. This won’t just affect coastal weather with more intense storms; it will alter inland weather, like ours. Next time you look at the clouds building up for a downpour you might consider that the ocean isn’t as far away as we’ve thought.

There’s a lot of false consciousness about the oceans’ role on the planet. Not only do ocean currents, winds and water-cycles shape the earth’s climate, but most of the biosphere’s oxygen on which we completely depend comes from the phytoplankton in the oceans, the true lungs of the planet. We don’t want to mess with these instruments of life. No matter where we live we should do homage to the ocean and its life-giving water.


There are five major threats to ocean health, and they all result from land-based human corporate activities. Dead zones occur when the oxygen level in the ocean gets so low that underwater biodiversity is endangered. Fish and crabs typical of a healthy seabed get replaced with layers of sediment filled with bacteria. The spread of oxygen-depleting plankton which feeds on agricultural fertilizers in runoff is considered central to this “deadening”. There were few dead zones in the 1960s, but by this decade, over 400 coastal dead zones have been documented; this escalation is mostly due to the spread of chemical agriculture. One of the largest dead zones is in the Baltic Sea; in the Gulf of Mexico a dead zone mushrooms during the agricultural growing season and then undergoes some biological recovery when the agricultural discharges stop. Restoring ocean health clearly requires a shift in human practices on land.

Rising ocean acidity also threatens biological stability. In one century there has been a .15 drop in Ph, and if the rate continues ocean water could go outside the chemical range within which biological evolution has occurred. The calcium in shellfish could deteriorate and quick regime changes in aquatic life could occur. Anyone who has had an aquarium knows that the health of its “pets” depends on maintaining chemical stability. Too much acidity will kill the kid’s fish.

Fossil fuels don’t just threaten ocean health through contamination, such as from BP’s oil drilling disaster. Ocean acidification is caused by the massive global burning of fossil fuels; as C02 rises in the atmosphere it also rises in the oceans which makes them more acidic. This provides more evidence of the pressing need for a quick transformation to renewable forms of energy.  Acidification combined with ocean warming also accelerates deterioration of the world’s coral reefs. Over the last quarter century bleaching has occurred on all tropical reefs. Because of their rich biodiversity the reefs are often called “the rain forests of the ocean”. On “Planet Water” it would be more accurate to call the rainforests “the coral reefs of the land.”


We all know about the collapse of the cod off Canada’s east coast. But it hasn’t yet sunk in that the majority of ocean fish are threatened by industrial extraction. The big ocean fish have declined by 90 percent over the last century, and the resilience of many fish species is now questionable. The decline of so many species at once can quickly unravel the biodiversity of marine eco-systems.

Overfishing has escalated over the last century. First, many rich river systems were depleted; then many coastal areas. Now industrialized “fishing” threatens deep sea life.  As one species is depleted, the fishing industry moves on to overfish another, and on it goes. Sharks, which bear few offspring, are now also in decline, being overfished for a lucrative Asian shark-fin soup. The oceans are treated as an unlimited resource to satisfy humanity’s voracious appetite; economic growth is literally killing the oceans.

Lastly, and most telling, is all the human-produced debris that ends up in the oceans. Non-biodegradable plastics are building up in ocean gyres, large systems of rotating currents, like vortexes, to form a soup of toxicity. We have unknowingly made the ocean the planet’s largest landfill site. One plastic-gathering gyre off Hawaii may be as big as Texas. Marine biologists are concerned that these plastics will enter the planet’s food chain and threaten the nutrient cycle needed for ocean health.


Knowledge of these interrelated threats to ocean health can be overwhelming. But marine biology specialists don’t always connect the dots among the ocean hot spots to see the larger picture or the common socio-economic causes. Scientists, too, can fall victim to compartmentalization. But thankfully Canada’s world-renowned environmental journalist, past environmental reporter for the Globe and Mail, Alanna Mitchell, took the time to connect many of the dots. After visiting researchers working on these five ocean threats she crawled into bed and went into what she called a “clinical depression”, until she could muster the perspective and energy to write Sea Sick: the Global Ocean in Crisis.

You might want to read her book but avoid the depression. Getting depressed after discovering what we are doing to the oceans will not help the oceans to recover. That will take committed political and economic action. A few courageous scientists and activists have worked on this for decades, but change will require collective muscle. And the oceans can’t wait much longer for us to alter our ways.

Next time I’ll discuss how those studying ocean health are pioneering the paradigm shift to sustainability.

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