Water in the Atmosphere

Front

Water Cycle Noun

---

[waw-ter sy-kuhl]

Back

Water Cycle

---

The continuous movement of water on, above, and below the surface of the Earth, driven by solar energy and gravity.

---

Example: This diagram shows how the sun's energy causes evaporation, leading to condensation, precipitation, and collection in a continuous cycle.

Front

Evaporation Noun

---

[ih-vap-uh-rey-shuhn]

Back

Evaporation

---

The process by which molecules of liquid water are heated by the sun and change into a gas called water vapor.

---

Example: This image shows the entire water cycle, where evaporation is only one of four steps shown.

Front

Condensation Noun

---

[kon-den-sey-shuhn]

Back

Condensation

---

The process by which water vapor in the air cools down and changes back into liquid water droplets.

---

Example: When warm, moist air touches a cold glass, the water vapor cools and forms liquid water droplets on the surface.

Front

Dew Point Noun

---

[doo point]

Back

Dew Point

---

The specific temperature at which air becomes saturated with water vapor and condensation begins to form on surfaces.

---

Example: As a parcel of air rises and cools, its temperature drops until it matches the dew point, causing water vapor to condense and form a cloud.

Front

Precipitation Noun

---

[pri-sip-i-tey-shuhn]

Back

Precipitation

---

Any form of water, such as rain, snow, sleet, or hail, that falls from clouds to Earth's surface.

---

Example: Rain falling from clouds onto the ground is one form of precipitation.

Front

Cycle Noun

---

[sy-kuhl]

Back

Cycle

---

A series of events or processes that are regularly repeated in the same specific order over and over again.

---

Example: The life cycle of a plant shows a repeating series of stages, from a seed to a mature plant that produces new seeds.

Front

Transpiration Noun

---

[tran-spuh-rey-shuhn]

Back

Transpiration

---

The process where plants absorb water through their roots and then release water vapor from pores in their leaves.

---

Example: This diagram shows how a plant pulls water in through its roots, moves it up the stem, and releases it as water vapor through pores (stomata) in its leaves.

Front

Respiration Noun

---

[res-puh-rey-shuhn]

Back

Respiration

---

The process in animals of releasing water vapor into the atmosphere during exhalation, or breathing out.

---

Example: This image shows the mechanics of breathing, including how the lungs and diaphragm work during inhalation and exhalation.

Front

Dew Noun

---

[doo]

Back

Dew

---

Liquid water in the form of droplets that condenses from the air onto cool surfaces, typically overnight.

---

Example: Water droplets, called dew, have formed on a cool plant leaf overnight.

Front

Frost Noun

---

[frost]

Back

Frost

---

A thin layer of ice crystals that forms on surfaces when water vapor changes directly into ice.

---

Example: A diagram showing how water vapor in the air turns directly into ice crystals on a leaf when it gets cold.