Amanda Morgan, age 14, of Chesapeake, West Virginia, for her question:

Where exactly is the Gulf Stream?

Actually it is an enormous eddy of water that swirls around in the North Atlantic Ocean. Though a circle has no end and no beginning, we might claim that the Gulf Stream begins where powerful forces start the great ocean current on its way. This is just north of the equator, where the strong prevailing trade winds drive a mighty stream westward from Africa toward Central America. However, a great ocean current is not strong enough to challenge the land.

Solid shores act as impossible barriers in its way and turn the course of its streaming energy. It travels northward off the coast of North America as far as Labrador, where a strong cold current from the Arctic makes it turn again. On this lap of the circle, the Gulf Stream travels eastward across the North Atlantic. It sends fingers of warm water around the shores of Northwestern Europe. But the main current is forced southward almost to the equator, where the eddying stream starts around the ocean again.