Water Cycle and Clouds

Water Cycle

by Meredith Jones

​Evaporation

​Evaporation

Evaporation turns liquid water into a gas called water vapor. In the process, the bonds between different water molecules are broken. Purified water vapor rises into the atmosphere, leaving salt and sediment behind.​

Open Ended

What is evaporation?

Multiple Choice

What causes evaporation?

• Rain

• Heat from the Sun

• Cold from the Sun

• Clouds

Condensation​

​Condensation

​After evaporation, water vapor rises high into the atmosphere. Air pressure and temperature drops the higher the vapor gets. This cools the water vapor. The water vapor clings onto particles of dust, smoke, and salt in the air, changing the vapor into droplets.

Open Ended

What is condensation?

Open Ended

Where can you find condensation in real life?

Clouds​

​Clouds

The droplets group together to form clouds. However, they are still too small to be seen. As more vapor condenses, the cloud droplets grow in size. An enormous group of cloud droplets make the clouds we see in the sky.

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There are many different kinds of clouds. The shapes they take give them their names. Cirrus clouds are thin, white, and wispy. Stratus clouds form thick layers of gray. Altostratus clouds cover the sky. Cumulus clouds are thick and grow upward. They have dark bases with mounds of white puffs. When cumulus clouds produce rain they are called cumulonimbus. They are often thunderstorms, dark and heavy with rain.​

Open Ended

How are clouds formed?

Poll

Which cloud type do you find most interesting?

Precipitation​

​Precipitation

​The water that falls back to Earth is called precipitation. Rain, hail, snow, and sleet are all forms of precipitation.

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​Precipitation falls as rain when temperatures are above 32 degrees Fahrenheit. Water returns to Earth most often as rainfall.

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​When temperatures are below freezing, precipitation falls as snow, sleet, or freezing rain. Snow is made of frozen ice crystals and falls in loose flakes. Sleet is falling snow that melts and refreezes before reaching the ground. Freezing rain occurs when snow melts as it falls through warmer air and then refreezes on surfaces that are below freezing.

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​Hail is frozen water that falls as hard chunks or solid ice. It almost always forms in cumulonimbus clouds.

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Open Ended

Why does precipitation happen?

Poll

Which type of precipitation do you find most interesting?

Groundwater​

​Groundwater

​Groundwater is naturally filtered as it flows slowly through the earth.

​Groundwater is almost everywhere. Billions of gallons are stored deep underground. Some has been in its liquid state for millions of years. Because it does not receive heat from the sun, it does not evaporate. This mean it moves through the water cycle much slower than surface water. But eventually it finds openings, refilling wells and underground pockets called aquifers. It also bubbles and flows out of the earth as freshwater springs.

Open Ended

Tell me three things you learned about groundwater.

Runoff​

​Runoff

​Water moving across the land is called runoff. Surface runoff is a direct result of precipitation, such as rain or snow.

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If precipitation is not absorbed into the ground, it flows over the land as surface runoff. About one-third of precipitation becomes surface runoff. Time, weather, and geography affect its flow. Most surface runoff eventually makes its way into established bodies of water, such as lakes and rivers.

Open Ended

What are some examples of runoff?