Deep Nutrients: The Power of Ocean Upwelling

If surface water is pushed away from an area by wind, then water from below must move upward to fill the empty space.

If the rising water originates from the deep ocean where sunlight cannot reach, then it will be significantly colder than the sun-warmed surface water.

If organic matter from dead organisms sinks and decays in the deep ocean, then that deep water becomes a reservoir of minerals and nutrients.

If winds blow parallel to a coastline, then the Coriolis effect causes the moving water to bend at a 90-degree angle. If that bend is away from the land, then upwelling occurs.

If nutrient-rich water reaches the sunlit surface, then tiny plants called phytoplankton can perform photosynthesis and grow. If phytoplankton are abundant, then fish and other animals have plenty of food to eat.

If wind patterns and the Coriolis effect align correctly, then upwelling can happen along any coast or even in the open ocean where currents diverge.

If wind blows across the ocean and the Coriolis effect causes the net movement of water to be perpendicular to the wind, then this movement is scientifically defined as Ekman transport.

If upwelling zones provide the nutrients necessary for massive numbers of fish to thrive, then the world's most productive fishing grounds will be found in those specific areas.

If there is no wind to move the surface water, then no deep water will rise. If the Coriolis effect doesn't push the water away from the shore, then upwelling cannot be triggered.

If colder water has a higher capacity to hold gases like oxygen and carbon dioxide, then the rising water from the deep will bring those gases to the surface layers.

If El Niño causes the usual trade winds to weaken or reverse, then the force pushing surface water away from the coast disappears. If the push disappears, then the cold, nutrient-rich water stays trapped at the bottom.

If two currents or a current and a coastline move in opposite directions, then they are diverging. If this divergence occurs, then ocean upwelling is the result.

If large-scale upwelling requires constant global winds and deep ocean water, then it occurs along major continental coasts and along the Equator where trade winds meet.

If nutrients sink to the bottom over time, then the surface becomes depleted of them. If upwelling brings that bottom water back up, then the nitrate and phosphate levels at the surface will rise.

If phytoplankton are microscopic plants that use sunlight and nutrients to grow, then they are the first step in the marine food chain. Without them, the energy from upwelling could not be passed to fish.

If the wind blows directly toward the shore, it piles water up. If the wind blows parallel to the shore, then the Coriolis effect can push the water out to sea, allowing for ocean upwelling.

If a large body of very cold water is brought to the surface near a city, then it will cool the air sitting above it. If warm, moist air hits that cold water, then the water vapor condenses into fog.

If upwelling triggers a massive growth of microscopic plants, then the green pigment (chlorophyll) in those plants will change the color of the water.

If small amounts of nutrients can be mixed by storms or large waves, then upwelling is not the only way; however, it is the most powerful and consistent method for large-scale nutrient return.

If upwelling zones cover only 1 percent of the ocean but provide about 50 percent of the world's fish catch, then the process is essential for human nutrition and the global economy.