Connect evaporation and condensation on a global scale to understand how clouds form and how the water cycle sustains Earth.
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Definition of the water cycle.
"The circulation of water between the Earth's surface and the atmosphere is known as the water cycle."
Water evaporates from oceans and lakes, turns into clouds, falls as rain, and eventually flows back to the oceans.
Explanation of cloud formation and rain.
When water evaporates, the invisible water vapour is lighter than air, causing it to float upward into the atmosphere. As it travels higher above the Earth's surface, the surrounding air gets cooler and cooler.
Illustration of the water cycle based on Fig 8.9.
Water continuously moves between the Earth's surface and the atmosphere.
Note on water scarcity and conservation.
Even though the Earth is covered in water, most of it is stored in the oceans. Because ocean water is incredibly salty, it cannot be used directly for drinking, cooking, or watering crops.
Drag and drop the steps of rain formation.
Drag the steps into the correct order to show how rain forms.