Ocean Currents and Their Causes

Wendy Pierce introduces Lesson 9, focusing on ocean currents caused by uneven heating, water temperature differences, salinity, and wind. Lesson 9.1 involves experiments on water density, while Lesson 9.2 explores salinity and density through a complex setup. The lesson concludes with a demonstration of wind's impact on ocean currents.

What are the main causes of ocean currents discussed in the lesson?

• Only wind and salinity differences

• Uneven heating of the Earth, temperature differences, salinity differences, and wind

• Only temperature differences and wind

• Only salinity differences and uneven heating of the Earth

Why does the equator receive more direct sunlight than the poles?

• The density of sunlight is greater at the equator

• The Earth is flat at the equator

• The equator is closer to the sun

• The poles are covered in ice

What happens when dyed warm and cold water are placed in room temperature water?

• Warm water sinks and cold water floats

• Both warm and cold water mix evenly

• Both warm and cold water float

• Cold water sinks and warm water floats

What is demonstrated by blowing a straw into warm water?

• Cold water upwelling

• Warm water upwelling

• Mixing of warm and cold water

• Evaporation of water

How is the salinity of water tested in the lesson?

• By measuring the water's pH level

• By tasting the water

• By measuring the temperature

• By coloring and observing the water's movement

What is the purpose of freezing and melting saltwater in the lesson?

• To observe changes in water color

• To measure the temperature of the water

• To observe density changes and salinity levels

• To create ice sculptures

What is the main finding from the salinity experiment?

• The water surrounding the ice is less salty

• The ice is saltier than the surrounding water

• The regular seawater is the saltiest

• The water surrounding the ice is much saltier and denser

What simple material is used to demonstrate the effect of wind on ocean currents?

• Salt

• Talcum powder

• Sand

• Sugar

What does the talcum powder demonstration show about ocean currents?

• Currents are unaffected by wind

• Wind causes ocean currents

• Currents move in a straight line

• Currents are only caused by temperature differences

What is the overall lesson about ocean currents?

• They are only caused by salinity differences

• They are only caused by temperature differences

• They are caused by a combination of factors including uneven heating, temperature, salinity, and wind

• They are only caused by wind