2.2 - Bodies of Water

Bodies of WaterBodies of Waterand and

LandformsLandforms

You may have noticed the blue parts of the maps. That’s water. No, really.

• Oceans and seas are the saltwater parts.

• There are four main oceans (Pacific, Atlantic, Indian, Arctic) although they’re really part of one big interconnected ocean

• The ocean has warm and cool currents (they’re represented by the red and blue arrows on the big map)

• These currents affect world temperatures because the water warms or cools the wind that blows over them. Ever wonder why England, though it’s on the same latitude as Canada isn’t nearly as cold or snowy? It’s because of ocean currents.

Lakes, rivers, and streams

• Generally freshwater. There are saltwater lakes when there are no outlets to the sea because the salt builds up.

• The saltiest lake is the Dead Sea in Israel and Jordan. It has no outlet and a high evaporation rate, so the salt concentrates even more. It’s so salty (about nine times that of the ocean), it can’t support life.

• Its shores are also the lowest dry point on Earth: about 1,350 feet below sea level (you’re currently about 45 feet above sea level)

• And the salinity (saltiness) allows you to float without effort. Like these guys:

That’s because the water is so much denser than you that it makes you naturally buoyant.

Just don’t get the water in your eyes. It’ll sting.

Hydrologic Cycle

• Water evaporates from various sources, goes up into the atmosphere, cools and condenses, comes down as rain or snow, and the process starts over again. It’s the cycle of water.

Drainage Basin

• The area drained by a major river and its tributaries

Water Table

• The water table is the point at which the ground and rock becomes saturated with water.

• The water table isn’t constant. It raises or lowers depending on seasonal recharge from rain and also from how much is pumped out.

• Overpumping can be a problem and can not only dry up wells, but also dry up streams that are fed by natural springs that use ground water.

Landforms

• Naturally formed features on the surface of the earth

• See pp. 34-35 for some different types (note that it’s an illustration and they don’t all occur within so little space)

• Continental shelf

• The point at which the edge of the continent drops off to the deep part of the ocean.

• The ocean floor has landforms as well as dry land.

• Relief is the difference in elevation of a landform from its lowest to highest points. The bigger the difference, the greater the relief.

• Topography is the combination and distribution of different landforms in an area