Walter Borowski, age 12, of Cleveland, Ohio, for his question:
What exactly is the Humboldt Current?
Oceanographers are still charting the vast currents that stream through the worldwide ocean. Like the currents in the weathery air, these watery currents are governed by set regulations of nature. They are interrelated in a world wide system. And the Humboldt Current is just one limb in this planetary system.
The waters off the shores of Peru are chilly, even as they sweep or their northward way as far as the equator. This streaming ocean river is the Peru Current, alias the Humboldt Current. Like all the many surface ocean currents its direction is determined by planetary prevailing winds. Its cool temperature is also caused by prevailing winds which continually blow the warm, surface waters out to sea, causing the cold waters of the deeper ocean levels to rise and replace them. When this strong cold current approaches tropical latitudes, its course is turned and swept westward out to sea. Most of its waters join a swirling system of currents that eddy through the vast South Pacific Ocean.
The Humboldt Current is merely one limb in this complex system of Southern Pacific ocean currents. But it is rated as one of the world's most vital ocean currents. Off Peru, its waters are at least 15 degrees cooler than the surrounding sea. But they are rich waters, rich in minerals and rich in sea dwelling plants and animals. Vast throngs of birds and teeming land animals thrive on the riches of the Peru Current.
Marine life usually is more abundant in the cooler waters of the world. The polar seas support immense meadows of floating plankton. This plankton mixture is a nourishing seafood salad of algae and diatoms, a large assortment of miniature sea animals, which feed on the tiny plants. Larger and still larger sea dwellers gather to feed on the plankton and on each other.
The abundant sea life continues even as the Peru Current streams through the tropical ocean. Here the seabed plunges to great depths and natural forces cause constant surges of deep water to well up to the surface. This deep water is loaded with chemicals dissolved from the extensive mineral deposits on the floor of the ocean. It is water teeming with nourishing food to feed swarming hordes of assorted sea dwellers. Big fish feed on smaller fish, smaller fish feed on still smaller creatures. Gulls and other seabirds swoop down and fill their crops. Assorted animals on the nearby shores also thrive on the products and the by products of the cold, rich Humboldt Current.
The Galopagos Islands lie in the path of the lively current, where its waters turn westward in turbulent eddies through the tropical Pacific. And these islands are the home of the world's most amazing collection of animal life. There we find ancient, well fed turtles and even penguins. Naturalists suspect that the ancestors of these tropical penguins were swept north by Antarctic gales. They survived and thrived because their new island homes were washed by the cool, banquet rich waters of the Humboldt Current.