Table
of Contents

The Weather Book
by Michael Oard

Lesson 4

Chapter 3 (pp. 20–31)

Textbook

The Weather Book, by Michael Oard.

Text

Water in the Atmosphere (pp. 20— 21)

Vocabulary Words

condensation
evaporation

Discussion Questions

1. Locate the vocabulary words in the glossary. Write the definition for each.
2. Half of the water for rain or snow comes from plants, wet ground, rivers, and lakes. Where does the other half come from?
3. When ocean water evaporates into the air as water vapor, what replaces it?
4. Where the water table is deep in the ground, the land is dry. Where in the world is this the case? (Use the map on page 11.)
5. Runoff from rainstorms carries chemicals from the soil to the ocean. If the chemical composition is off-balance and becomes harmful to plankton, how could the rest of the ocean suffer?

Text

Clouds (pp. 22—25)

Vocabulary Words

cirrus clouds
convection clouds
cumulus clouds
fog
relative humidity
stratus clouds

Discussion Questions

1. Locate the vocabulary words in the glossary. Write the definition for each.
2. How do clouds form?
3. Which holds more water: warm air or cool air?
4. What do fog, mountain clouds, convection clouds, and frontal clouds all have in common?
5. What are the three basic cloud types?
6. When are cumulus clouds usually seen?
7. Which of the three basic cloud types contain ice crystals?
8. Which cloud type is found at low altitudes?
9. Clouds are classified according to their __________ in the sky.
10. Which two cloud types may contain rain?

Text

Warm Fronts and Cold Fronts (pp. 26—29)

Discussion Questions

1. What is a warm front?
2. What causes most cloud and precipitation formation?
3. What force pulls water droplets to the ground?
4. What are the indications of an approaching warm front?
5. What weather conditions occur along with a warm front?
6. From which direction do cold fronts usually come in the northern hemisphere?
7. Which is more dense: cold or warm air?
8. During the summer, what weather conditions indicate a cold front is passing through?

Text

Fog (pp. 30—31)

Discussion Questions

1. List and describe the four types of fog.
2. The air can hold no more water when it reaches its __________.
3. When could fog prove to be hazardous to people?
4. What is the relationship between fog and clouds?
5. Which types of fog occur over water?
6. Which types of fogs occur over land?

Answer Key

Water in the Atmosphere (pp. 20—21)

1. See glossary.
2. It evaporates from the ocean.
3. Rainwater.
4. See semi-arid and arid climates.
5. Plankton is the bottom of the ocean food chain. Sea life depends on it for survival.

Clouds (pp. 22—25)

1. See glossary.
2. Clouds form when the atmosphere can no longer hold all of the invisible water vapor so it condenses into water droplets or ice crystals.
3. Warm air.
4. They are all formed by moist air cooling enough to form clouds.
5. Cumulus, cirrus, and stratus.
6. Usually on a bright, sunny day.
7. Cirrus.
8. Stratus.
9. Height.
10. Cumulonimbus and nimbostratus.

Warm Fronts and Cold Fronts (pp. 26—29)

1. Warm air pushes the cold air back and warmer air rises above it.
2. Most clouds and precipitation are formed as air rises into the atmosphere.
3. Gravity.
4. We can tell when a warm front is approaching by the type of clouds observed – high clouds first, then thicker and lower clouds.
5. When the warm front is close, the clouds are low and precipitation falls.
6. North or west.
7. Cold.
8. Thunderstorms.

Fog (pp. 30—31)

1. Evaporation, advection, radiation, upslope.
2. Point of saturation, dew point.
3. Accept reasonable answers.
4. Fog is a cloud that forms on the ground.
5. Evaporation and advection.
6. Radiation, upslope, and advection.