Charles Zweig, age 12, of Gary, Ind.
What causes iceberg to form?
An iceberg is the daughter of a glacier. It is born at the edge of same giant ice field in the polar regions. To look at it, you might think that a mighty glacier is frozen still, that it never moves. Actually, every glacier is on the move, It flows very slowly, like a frozen river, which is what it really is. New snowfalls are always adding weight to the surface of the massive sheet of ice. This extra weight forces the mass of ice to move. A mountain glacier moves slowly downhill.
A vast flat ice sheet moves slowly out from the center. Sooner or later, the edges of the glacier reach the sea. Here they meet the pounding waves which are always a little warmer than the ice. The pounding sea weakens and cracks the great wall of ice and huge chunks break off and fall into the water. These giant ice cubes become icebergs, drifting at the mercy of the winds and ocean currents.