Weather Unit Test Review

1. A boundary in which two different air masses meet and do not mix, causing a change in the weather is:

• a. the jet stream

• b. the greenhouse effect

• c. air pressure

• d. a weather front

Answer explanation

A weather front is the boundary where two different air masses meet and do not mix, leading to changes in weather. This distinguishes it from the jet stream, greenhouse effect, and air pressure, which do not specifically describe this phenomenon.

2. A large section of air with the same temperature and moisture level is called ________________.

• a. a pressure gradient

• b. an air mass

• c. a hemisphere

• d. a hurricane

Answer explanation

A large section of air with uniform temperature and moisture is known as an air mass. This term specifically describes the characteristics of the air, making option b the correct choice.

5. What is humidity?

• Water, in liquid or solid form, that falls from the atmosphere.

• The atmospheric conditions, along with short-term changes, of a certain place at a certain time.

• The amount of water vapor in the air.

• The force that a column of air applies on the air or a surface below it.

Answer explanation

Humidity refers to the amount of water vapor in the air, which is crucial for understanding weather and climate. The other options describe different atmospheric phenomena, but only this choice accurately defines humidity.

6. In general, how does air move around the Earth?

• a. from areas with deeper ocean to areas with shallower oceans

• b. from areas of lower air altitude to areas of higher air altitude

• c. from areas of higher temperature to areas of lower temperature

• d. from areas of lower temperature to areas of higher temperature

Answer explanation

Air moves from areas of higher temperature to areas of lower temperature due to differences in pressure. This movement helps to equalize temperature and pressure across the Earth's surface, driving weather patterns.

8. A cold front moving into an area can bring what type of weather?

• a. warmer temperatures, clear and sunny skies

• b. cooler temperatures, clear skies

• c. warmer temperatures, clouds

• d. cooler temperatures, clouds, and precipitation

Answer explanation

A cold front typically brings cooler temperatures, increased cloud cover, and precipitation as warm air is forced upward, leading to weather changes. Thus, the correct answer is d: cooler temperatures, clouds, and precipitation.

10. What is the source for global winds and convection in the atmosphere?

• a. unequal heating of the Earth by the Sun

• b. the rotation of Earth

• c. the moon’s gravity

• d. continental

Answer explanation

The source of global winds and convection in the atmosphere is primarily due to the unequal heating of the Earth by the Sun. This causes temperature differences, leading to air movement and wind patterns.

14. High pressure is associated with what type of weather?

• a. cloudy weather

• b. cold weather

• c. warm weather

• d. fair/good weather

Answer explanation

High pressure systems are typically associated with descending air, which leads to clear skies and stable weather conditions. Therefore, high pressure is linked to fair or good weather, making option d the correct choice.

18. Where does the initial source of energy come from that creates winds and thus surface currents?

• a. the moon’s gravity

• b. the sun

• c. the rotation of the Earth

• d. wind

Answer explanation

The initial source of energy that creates winds and surface currents is the sun. Solar energy heats the Earth's surface unevenly, causing air movement and thus generating winds, which in turn drive ocean currents.

19. In the figure, which of the following is the correct symbol for a cold front?

• a. 1

• b. 2

• c. 3

• d. 4

Answer explanation

The correct symbol for a cold front is represented by choice 1, which typically consists of blue triangles pointing in the direction of the front's movement. This distinguishes it from other weather front symbols.

21. ________________ are made of water vapor that condenses in the atmosphere.

• a. dew

• b. clouds

• c. evaporation

• d. transpiration

Answer explanation

Clouds are formed when water vapor in the atmosphere cools and condenses into tiny water droplets or ice crystals. Therefore, the correct answer is b. clouds.