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.

3. The Sun strikes the Earth the most at the Equator and the least at the poles. This causes warm air to ____________ from the equator and cold air to ___________ at the poles.

• a. stay, leave

• b. leave, stay

• c. rise, sink

• d. sink, rise

Answer explanation

The Sun heats the Equator more, causing warm air to rise there. Conversely, at the poles, the air is cooler and denser, leading it to sink. Thus, warm air rises from the equator and cold air sinks at the poles, making 'rise' and 'sink' the correct choices.

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.

9. The name of the instrument used to measure wind speed

• a. anemometer

• b. meter stick

• c. thermometer

• d. barometer

Answer explanation

The correct instrument to measure wind speed is an anemometer. A meter stick measures length, a thermometer measures temperature, and a barometer measures atmospheric pressure.

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.

13. Which of the following statements best describes the climate of an area rather than its weather conditions?

• a. The summers are hot and humid.

• b. The temperature at noon was 86°F.

• c. Total rainfall on April 9 was 2 inches.

• d. Strong winds are expected tomorrow evening.

Answer explanation

The statement "The summers are hot and humid" describes the long-term climate characteristics of an area, while the other options refer to specific weather conditions or events.

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.