What Causes Wind
Understand how uneven heating can help create a daytime sea or lake breeze: air warmed over land spreads out and can rise while cooler air flows inland near the ground. Wind is moving air.
What a learner can do afterwards
- Explain that the Sun heats Earth's surface unevenly
- Describe a daytime sea breeze in which air warmed over land can rise while cooler air flows inland near the ground
- Define this air movement as wind
1 · Read
You know wind is moving air. The Sun warms Earth's surface unevenly. On a sunny day, land can warm faster than nearby water. That can help start a breeze between them. Winds also blow in larger weather systems.
Warm ground heats nearby air. As that air warms, it spreads out. The same amount of air takes up more space. It can rise through cooler air around it. In a daytime sea or lake breeze, air rises over warm land while cooler air flows in near the ground. Air keeps moving, without leaving an empty gap.
In a daytime sea breeze, warm air rises over land as cooler air flows inland from the sea. This moving air is wind. Higher up, air flows back toward the sea and sinks, completing a loop.
A sea breeze is one example of wind. Larger weather systems also bring winds. Hills and buildings can change their speed and direction.
Uneven heating can help start a breeze. Warmed air can rise while cooler air flows in near the ground. Wind is moving air.
Rewritten readings were written for this dataset.
2 · Watch
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Where it sits
Where this leads
Jobs that lean on this skill. Follow one to see everything it is built on.
8 questions wait behind this lesson, each with its answer explained. Every answer feeds the sky: stars light as they are learned, and dim when it is time to come back.