Lesson 2 Circulation in Earth's Oceans Exp 2

Lesson 2 Circulation in Earth's Oceans Exp 2

Using Warm and Cold Water

Hot and Cold Water

Hot and cold water have different properties because of the difference in their temperatures. Cold water has slow moving particles that have less energy. Warm water particles bounce around more and spread a little farther apart than particles in cold water. This makes warm water less dense.

Multiple Choice

What will happen to the warm water in this lab?

• the warm water will stay at the bottom

• the warm water will move upwards

Multiple Choice

Why does the warm water move upwards?

• it is more dense

• it is less dense

Multiple Choice

In which lab did the water not move?

Multiple Choice

Why did the warm and cold water stay in the same place?

• because warm water is less dense and the cold water is more dense

• cold water is less dense and warm water is more dense

Density Differences in Water

Density is the measure of the amount of mass in a given volume of a substance. If you put a piece of metal in water the metal has greater density than the water.

Density Differences in Ocean Water

Ocean water is not all the same. Not all ocean water has the same amount of dissolved salt. The temperature of ocean water varies as well. Temperature and salinity both affect the density of ocean water.

Multiple Choice

What 2 factors both affect the density of ocean water?

• temperature and the sun

• temperature and ice

• temperature and salinity

• salinity and ice

How can salinity be affected in the Ocean?

• Temperature and salinity both affect the density of the ocean

• Increase in salinity will make water denser

• The salinity of the ocean can be changed by rain fall

• The salinity of the ocean can be changed by evaporation

• The salinity of the ocean can be changed by formation of ice in the ocean water

• By the addition of fresh water

Multiple Choice

Why did the egg float in the salt water?

• the egg was more dense than the fresh water

• the egg was less dense than the salt water

Multiple Choice

Why did the egg sink in the fresh water?

• The egg was more dense than the fresh water.

• The egg was less dense than the salt water.

The Formation of Deep Currents

Density of ocean water will increase if the water becomes colder or if the salinity increases. Denser water sinks. Deep ocean currents are the movement of water in regular patterns below the surface of the ocean.

Factors that Affect Deep Currents

• Deep currents are driven by density differences in ocean water and by gravity.

• At Earth's poles, surface water cools and becomes denser.

• The cold, dense water moves in the deep ocean toward the equator, forming a deep current.

• Deep currents flow along the ocean floor or along the top of another layer of water.

• Several layers of deep currents can occur at any place in the ocean.

Multiple Choice

How can fresh water dilute salt water to make it less salty?

• evaporation

• river pouring into the ocean

• formation of ice in ocean water

The Formation of Deep Currents

The density of ocean water will increase if the water becomes colder or it the salinity increases. If this happens ocean water at the surface can become denser than the water below it. The denser water sinks. Deep ocean currents are the movement of water in regular patterns below the surface of the ocean.

Factors that Affect Deep Currents

Deep currents are driven by density differences in ocean water and by gravity. At Earth's poles, surface water cools and becomes denser. The denser water is pulled towards the ocean floor by gravity more strongly than less dense water is and sinks. The cold, dense water moves in the deep ocean toward the equator, forming a deep current.

Factors that Affect Deep Currents

Deep currents flow along the ocean floor or the top of another layer of water. As a result, several layers of deep currents can occur at any place in the ocean. Coriolis effect causes deep ocean currents to be deflected in the same way that surface currents are deflected.

Multiple Select

Check all that apply. What are some factors that affect Deep Ocean Currents?

• gravity

• Coriolis affect

• density

• sharks and dolphins