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Course: Middle school Earth and space science > Unit 3
Lesson 1: The water cycleThe water cycle
Google ClassroomReview your understanding of the water cycle in this free article aligned to NGSS standards.
Key points:
- The water cycle describes how water continuously moves between Earth’s surface and the atmosphere.
- This movement occurs by different physical processes.
- Water moves into the atmosphere from oceans, lakes, and streams by evaporation. During evaporation, water changes from liquid water to water vapor (a gas).
- Water also moves into the atmosphere by transpiration, or the evaporation of water from plants. Both evaporation and transpiration are driven by the sun’s energy.
- Water forms clouds in the atmosphere by condensation. During condensation, water changes from water vapor to liquid water.
- Water falls down to Earth’s surface by precipitation. This process is driven by gravity. Of the water that reaches land, some flows downhill as runoff and some soaks into the ground to become groundwater.
Want to join the conversation?
So transpiration can happen to all plants?(39 votes)
Transpiration in plants occurs in all living species with few exceptions, so whether you own an orchard or are growing a lawn, transpiration is an essential active process.(48 votes)
why do plants evaporate water?(7 votes)
Plants have small holes in their leaves called stomata that water evaporates through. Evaporating water through the stomata creates a capillary action that draws new water into the plant through its roots. The capillary action is advantageous for two reasons. First, it allows the plant to pump water from the ground to its leaves without using energy. Second, cycling new water into the plant provides it with fresh nutrients.(25 votes)
what happens if we cover the ocean(9 votes)
The vapor would go through it but if we use metal it would just keep all the vapor inside of the metal and when we take it off you will see a lot of vapor.I wonder if that would form new clouds live?(11 votes)
- Can you physically see the evaporation happening(8 votes)
- If you have a container of water that no water is being added to and you watch it closely, then you will eventually observe that there is less water in it than before.(11 votes)
- what happens if there was no sun?(0 votes)
- written by AI: If there was no sun, life on Earth would not be possible as we know it. The sun provides heat, light, and energy essential for sustaining life. Without the sun's energy, Earth would become extremely cold, and photosynthesis, which is the process by which plants convert sunlight into energy, would not occur. This would disrupt the food chain, leading to a loss of plant and animal life. Additionally, the sun's gravitational force helps to keep Earth in its orbit and maintains the stability of the solar system. Overall, the absence of the sun would have a catastrophic impact on Earth's climate, ecosystems, and the survival of living organisms.(19 votes)
- HOW do we still have water if we keep drinking it like the dinosaurs did(5 votes)
because of the water cycle ....
The water cycle recycles all the water again and again which tells us that the water is really , really old .(8 votes)
Does water ever go away?(6 votes)- No, water keeps changing forms but still remains unless something drinks it which im not too sure on what happens(6 votes)
- Does evaporation happen at night.(2 votes)
- Evaporation happens at night and during the day. Evaporation happens faster at higher temperatures and more slowly at lower temperatures. So, typically there is less evaporation at night.(13 votes)
- is the sun the only thing that can make water evaporate?(9 votes)
Nope :O
In fact, any substance in liquid state, including water, will naturally evaporate. It's normally a very slow rate, but the higher the temperature above melting point, the higher the rate of evaporation... until the temperature reaches the liquid's boiling point. So you don't need the Sun, you just need to put in the heat to make water a liquid, which is normally already done unless you put it in the refridgerator or something.
Fun fact: Mercury is the only metallic element that's a liquid at room temperature, and it releases invisible mercury gas fumes at a slow rate that you shouldn't breathe in.
Happy learning!(1 vote)
How does water form again if the cycle stops?(5 votes)
Water does not form again. It is just in a different state of matter. The water cycle doesn't stop, it keeps on going.(7 votes)