Raoul Lopez, age 11, of Utica, N.Y., for his question:
WHICH IS THE SMALLEST OF THE GREAT LAKES?
The five North American Great Lakes are the largest group of freshwater lakes in the world. The smallest, which is also the most eastern, is Lake Ontario.
Lake Ontario forms an important link in the St. Lawrence Seaway system. Although it is open to large ships throughout the year, it has less traffic than the other Great Lakes.
Lake Ontario lies between the province of Ontario and the northwestern part of New York. The lake is about 193 miles long and 53 miles wide. It covers an area of 7,550 square miles. The shore of the lake is about 480 miles around.
Offshore, Lake Ontario is very deep, ranging from 500 to 802 feet. Its surface lies 245 feet above sea level.
The great depth of Lake Ontario, together with its low lying surface, means that two thirds of its waters lie below sea level and are not touched by surface winds and currents. A steady top current moves across the lake from west to east at a rate of about one third mile per hour.
Lake Ontario does not freeze in winter, except along the shore where the water is more shallow. The depth of its waters makes its surface cooler than the air above it in summer, and warmer in winter.
The lake has a moderating effect on the climate of the area. The eastern outlet of the lake never has a really hot day, and the temperature of the southern shore is so moderate that fruit trees grow throughout this region on both sides of the United States Canada border.
Lake Ontario empties into the Atlantic ocean through the St. Lawrence River. The Niagara River and the Welland Canal connect it to Lake Erie on the southwest. It is connected with the Hudson River and New York City by the Erie Canal, the Genesee River and the Oswego Canal. The rivers that empty into Lake Ontario include the Black, Genesee, Oswego, Trent and Humber.
Lake Ontario has many good harbors. The chief lake ports include Rochester and Oswego, N.Y., on the United states side and the Canadian ports of Coburg, Toronto, Hamilton and Kingston.
Of the five Great Lakes, only Lake Michigan lies entirely within the United States. Lake Ontario and the other three, namely Superior, Huron and Erie, are shared by the United States and Canada, and form part of the boundary between the two countries.
The Boundary Waters Treaty of 1909 provides joint control of the lakes by these two countries.
Lake Ontario and the other four lakes in the group were formed about 250,000 years ago. At that time, a glacier moved south across the land. The glacier dug out deep depressions in the soft rocks of the region and picked up great amounts of earth and rocks.
The glacier withdrew from 11,000 to 15,000 years ago and the earth and rocks blocked the natural drainage of the depressions. Water from the melting glacier gradually filled in the depressions and formed the Great Lakes.