Joe Barrelia, age 14, of Greenville, miss., for his question:
WHAT IS THE GULF STREAM?
The Gulf Stream is the second largest ocean current. Only the Antarctic Circumpolar current is greater. The Gulf Stream has its source in the warm waters of the eastern part of the Gulf of Mexico. These waters pass through the Straits of Florida to become the Gulf Stream.
The Gulf Stream flows northeastward across the Atlantic toward Europe. The stream flows as fast as 138 miles a day. Its rate of flow, measured in volume per second, is about 1,000 times greater than that of the Mississippi River.
After the Gulf Stream flows through the Straits of Florida, it passes the Little Bahama Bank. The Antilles Current, which flows northwest along the Atlantic side of the West Indies, then joins it. The combined current continues northward, widening and slowing as it goes.
The Gulf Stream forms the northwest boundary of the Sargasso Sea, separating the warm waters of that sea from the chili waters of the North Atlantic. The stream is about 50 miles wide and 3,000 feet deep. It follows the Atlantic coast of North America.
A narrow strip of cold water, called the "cold wall," separates the Gulf Stream from the coast.
By the time the stream has reached Charleston, S.C., it has slowed to about 40 miles a day. At the Newfoundland Banks, it travels about 10 miles a day and ceases to be a strong current. It spreads out and becomes a general drift of warm water that moves eastward toward Europe. This part of the stream is the North Atlantic Current.
As the North Atlantic Current approaches Europe, it divides into two parts. One stream flows southward toward the west coast of Africa. The other moves northward toward the British Isles.
The Gulf Stream may be partly responsible for the warm southwesterly winds that make the climate of Great Britain and northwestern Europe much warmer than parts of North America that lie equally far north. These winds pick up heat and moisture from the Sargasso Sea and the Gulf Stream.
The warm winds associated with the Gulf Stream greatly influence ,the climate of the countries they touch. For example, the average January temperature in northern Norway is about 45 degrees Fahrenheit, higher than normal for that latitude.
The warm waters of the Gulf Stream keep many ports in northwestern Europe ice free ail winter. Hammerfest, Norway, is an important sea fishing center in winter, while Riga, Latvia, 800 miles south of Hammerfest, is icebound.
The Gulf Stream is also an aid to shipping. Many large oil tankers and ore carriers, traveling from South America to Atlantic coastal harbors, attempt to "ride" the Gulf Stream on their northbound journey. This enables them to save valuable shipping time.
Winds and currents are the main cause of the Gulf Stream. Trade winds cause a westerly flow of water where the Atlantic Ocean crosses the equator. These westerly currents are called the North and South Equatorial currents.
The South Equatorial Current flows west to strike the north coast of Brazil, where two fifths of its waters are directed into the Caribbean Sea. As it flows into the Caribbean, the South Equatorial Current reinforces the warm waters of the North Equatorial Current.