Layers: The World Ocean

LayersWorldOcean60x48The World Ocean…massive and powerful, covering seventy percent of our Planet Earth, home of the oceanic food web, regulator of the atmosphere, and the source of most of the oxygen we breath.  While we think of the Atlantic or Pacific Ocean as singular entities, they are all part of one World Ocean, connected one to another and exchanging their waters slowly but freely.  Of all the parts of the Earth’s system, the World Ocean is one of the most vulnerable because vulnerability in one part of this massive body of water is vulnerability in all.

Until about 150 years ago, humans believed they reaped the benefits of the ocean freely.  There were few people, compared to today’s seven billion, their impacts were small and local. The bounty of the sea, it seemed, could not be used up.  The fish of the sea had fed millions for millennia and yet seemed unlimited.  As demonstrated by cod, eaten by growing European populations with ever more sophisticated boats, technology, and preservation techniques, the “unlimited” stocks of the Grand Banks and nearby habitats have dwindled.  First the numbers of the prized large fish began to decline, with fewer 100-pound fish taken.  That left less of these large breeders to have offspring even as the demand for the fish grew.  Within about 50 years, the stocks of cod were seriously depleted and the fishermen began moving to other species in other waters.  Humankind had decimated one of Earth’s greatest resources, the cod fishery of the Grand Banks.  As with the cod, so did the whales suffer.  The demand for whale oil, meat and other pieces of these large mammals caused whale hunting to move from a subsistence craft to an industrial enterprise.  Declines in the larger whale species shifted hunting pressure to the smaller ones until only international agreements kept the whales from being completely extirpated.  Yet individuals of several species number only in the hundreds.

The exploding hunger for seafood, and other products of the ocean, and the increasing sophistication of the technology used to harvest the fish, has reduced the catch dramatically, leaving smaller and less desirable species after the bigger ones have been eaten.  “Feeding down the food chain” has resulted in a serious depletion of fish stocks across the ocean. The toll passes from one fishery to another; the assaults more numerous, and the effects longer lasting.  Ideas for “managed fishing” were tried and largely found lacking.  Sustainable fishing is becoming less and less of a reality, jeopardizing our ability to obtain protein from the sea.  Major fisheries have collapsed even as the hungry world demands more fish.

In the vastness of the ocean, it seems possible to dilute any poison while any amount of trash would be negligible in its vastness.  But as people multiplied, turning to the sea to get rid of waste and garbage, the problem grew.  Dump poison into the ocean and you poison ocean life, as well as the people eating seafood. The mercury tainted shellfish of Minamata, Japan proves the case, officially a case of poisoning and killing thousands.  Mercury accumulation is a serious problem beyond affecting shellfish and tuna.

Dumping, runoff, and poisons drifting down from the air have multiplied and are taking their toll.  Estuaries, the nurseries of the ocean, are suffering in the Boston Harbor, New York and the Jersey shore. The Chesapeake Bay and San Francisco Bay have been seriously assaulted.  The damage is visible and efforts taken to clean up these messes are less and less effective.  The Clean Water Act in the United States and similar efforts globally have helped but this protection is under attack by politicians claiming overregulation is anti-business.  Signs on storm sewers informing potential polluters where their effluvia are likely to end up cannot forestall the effects of big corporate polluters.  Increasing industrialization and consumerism of the developing world are adding pollutants in places never polluted before.  Vast swirls of plastic debris slowly rotate over a huge stretch of the Pacific while marine detritus fouls beaches worldwide, making eating, living and reproduction difficult for countless creatures.

All these visible, measurable assaults on ocean life seem small when compared to the new danger of ocean acidification.  The ocean’s uptake of carbon dioxide was once considered beneficial, as the more carbon the ocean absorbed, the less was left in the atmosphere to warm the globe.  However, with the ever-rising amount of carbon dioxide dissolving into the water from the atmosphere, the ocean is becoming more acidic.  While it will never approach the acidity of lemonade, the slight shift from an ocean more basic to one less basic, as the carbon dioxide accumulates, interferes with the biochemistry of calcareous shell building organisms, such as the single celled plankton, foraminifera and cocolithophores.  Their structures become frail and brittle as the chemical building blocks of their minute aragonite and calcite “skeletons” fail to properly form. The structure of their hard parts becomes compromised and they no longer thrive, causing plankton numbers to collapse. The organisms that would eat them then have less to eat and the populations of these grazers and their predators also collapse, potentially simplifying the world ocean’s food webs and diversity.

This “osteoporosis” of the ocean is perhaps more dangerous than the other effects from the burning of fossil fuels.  Global warming and rising sea levels will take their toll, over fishing and pollution are definite hazards, but ocean acidification may be the ultimate assault on the ocean.

No part of this text/essay may be copied or used without written permission from James Brey, PhD.

Additional Images

Layers: Places in Peril

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