"Nature Guide Journal"

13 July 2000

It's been a windy summer on the Oregon Coast--and that's a good thing.

Summer winds howl down from the arctic chilling unwary beachcombers. But the sustained winds also drive a near-shore current down the coast. The combined effect of the southerly-moving water and the earth's rotation pulls the surface water away from the shore. As the surface water moves offshore, water from greater depth wells up to replace it: "upwelling."

And upwelling's a good thing. The deep water is rich in nutrients, and upwelling draws those nutrients up to the light. There, they fertilize the microscopic plants (phytoplankton) that are the major producers of food and oxygen in the sea. The nutrients' rise to a sun-lit level causes a phytoplankton population explosion, or "bloom."

The increase in the plant plankton naturally leads to an increase in the animal plankton (zooplankton). More zooplankton leads to more larger animals, which in turn feed still larger animals...which includes us.

The upwelling water is a little saltier and denser than the offshore water, and quite a bit colder. Water in the surf zone during upwelling on the Oregon coast may be 43-45 degrees, while some 50 miles offshore the sea surface may be 55 degrees. In fact, the water on our beaches may be colder in the summer than it is in the winter.

When the wind does die down during coastal upwelling, the moist air warms up and condenses as it contacts the cold sea. The result is fog. Though sun-lovers may argue, fog is a good thing, too. Drifting inland, the fog cools and moistens the coastal forest during the summer's drought.

As you fasten your windbreakers on your next beach walk, remember, the cold north wind is great for the upwelling.

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Wavecrest Discoveries can craft your personal discovery of this delightful part of our world by customizing one of our distinctive guided excursions.   Our walks, tours, and special activities are wonderful ways to explore this fascinating region—and are the perfect entertainment for guests.