4-4.1 Summarize the processes of the water cycle (including evaporation, condensation, precipitation, and runoff).
The Water Cycle
Essential Question: What happens to water after it rains?
What makes Earth different from other plants in our solar system? The answer is water. Earth is the only planet with large amounts of liquid surface water. Without water, life on Earth would not be possible. Energy from the sun keeps water moving and changing. But the amount of Earth’s water stays about the same.
The Water Cycle
The water cycle is the movement of water between Earth’s surface and atmosphere. Water moves from the oceans and land into the air and back again. This diagram shows the water cycle.
A cycle is a process that does not have a beginning or end. It repeats over and over. But you can think of the water cycle as having four main steps.
Step 1: The sun warms liquid water on Earth’s surface. The sun’s energy makes some of the liquid water change to a gas. This change from a liquid to a gas is called evaporation. Water in the form of a gas is called water vapor. Water vapor rises into the air. It moves from Earth’s surface into the atmosphere.
Step 2: As water vapor rises, it cools off. When it gets cool enough, water vapor changes back to liquid water. This change from a gas to a liquid is called condensation. When a gas changes to a liquid, we say it condenses. Water vapor condenses into tiny droplets of liquid water. These droplets form the clouds that you see in the sky.
Sometimes water vapor condenses directly onto a surface such as grass, a car, or glass. The drops of water that condense in this way are called dew.
Step 3: Droplets of liquid water in clouds combine with other droplets to form bigger drops. When they become too big and heavy, they fall back to Earth’s surface as precipitation. Precipitation is water that falls from clouds. It includes rain, snow, hail, and sleet. Snow, hail, and sleet form when there are freezing air temperatures.
Step 4: Water falls into the oceans and onto land. On land, some water sinks into the ground, and some flows downhill over the ground. Water that flows over the ground is called runoff. It flows into bodies of water, such as rivers, lakes, and oceans. There, evaporation keeps the water cycle going.
Essential Question: What happens to water after it rains?
What makes Earth different from other plants in our solar system? The answer is water. Earth is the only planet with large amounts of liquid surface water. Without water, life on Earth would not be possible. Energy from the sun keeps water moving and changing. But the amount of Earth’s water stays about the same.
The Water Cycle
The water cycle is the movement of water between Earth’s surface and atmosphere. Water moves from the oceans and land into the air and back again. This diagram shows the water cycle.
A cycle is a process that does not have a beginning or end. It repeats over and over. But you can think of the water cycle as having four main steps.
Step 1: The sun warms liquid water on Earth’s surface. The sun’s energy makes some of the liquid water change to a gas. This change from a liquid to a gas is called evaporation. Water in the form of a gas is called water vapor. Water vapor rises into the air. It moves from Earth’s surface into the atmosphere.
Step 2: As water vapor rises, it cools off. When it gets cool enough, water vapor changes back to liquid water. This change from a gas to a liquid is called condensation. When a gas changes to a liquid, we say it condenses. Water vapor condenses into tiny droplets of liquid water. These droplets form the clouds that you see in the sky.
Sometimes water vapor condenses directly onto a surface such as grass, a car, or glass. The drops of water that condense in this way are called dew.
Step 3: Droplets of liquid water in clouds combine with other droplets to form bigger drops. When they become too big and heavy, they fall back to Earth’s surface as precipitation. Precipitation is water that falls from clouds. It includes rain, snow, hail, and sleet. Snow, hail, and sleet form when there are freezing air temperatures.
Step 4: Water falls into the oceans and onto land. On land, some water sinks into the ground, and some flows downhill over the ground. Water that flows over the ground is called runoff. It flows into bodies of water, such as rivers, lakes, and oceans. There, evaporation keeps the water cycle going.
ABDO Digital eBook: The Water Cycle
● Evaporation and Condensation ● Water Cycle Diagram ● Interactive Water Cycle _Discovery Education Video: ● The Water Cycle ● Weather Smart: The Water Cycle and Clouds Discovery techbook reading passage: 3..2..1..Blast off Condensation Video Clip Discovery Techbook Reading Passage: It's Only Water Thirstin's Water Cycle USGS: The Water Cycle |
Read “What Causes Clouds and Precipitation?” in Weather Instruments (page 6, Delta Science Readers).
Students set up experiments in which water evaporates and condenses. Students infer that evaporation and condensation involve a change in the form of water and learn that evaporation and condensation are inverse processes. (DOK 2) *Students observe one cube of ice on their desk throughout the day. Record times and observations. Hypothesize what the ice cube will look like the following morning. (DOK 3) *Students can construct and label the parts of the water cycle. (DOK 2) Write Like a Scientist: Make an accurate drawing of the water cycle. Use arrows and words to show the direction that the water cycle travels. Label all of the parts of the cycle. Write a detailed summary to explain how water changes form as it travels through the cycle. Cite your evidence. (DOK 2) |