Earth & Space Science
Learners will examine the formation and direction of sea and land breezes.
After completing this tutorial, you will be able to complete the following:
The formation of sea and land breezes must first be described through the process of currents. Currents are a continuous flow of water, air, or gas. Using the properties of heat, convection currents describe the movement of hotter or cooler parts due to the differences in density. Convection currents are circular in motion. This process creates the basis for which breezes along the shore are formed.
Water has a high specific heat capacity, which means that compared to most other materials, it is harder to heat. Once water is warmed up, it tends to keep its heat longer. During the day, the temperature of the land is greater than the temperature of the sea. As the time of day progresses, the temperature of the land increases. The warm air particles above the land are less dense and begin to rise. In contrast, the air above the sea is cooler and denser. This cool air above the sea rushes into the evacuated space of the warm air that has risen above the land. Thus a sea breeze has been created.
At night, this process works in reverse. The temperature of the land decreases more rapidly than the temperature of the sea. Again the warm air rises, and the cool air rushes into this evacuated space. This time the air rushes from the land to the sea creating a land breeze.
In conclusion, as the time of day changes, the speed and wind direction change due to the changes in temperature. These changes can be recorded using two instruments. An anemometer is used to measure the speed of the wind and the direction of wind is observed through the use of a weather vane.
|Approximate Time||20 Minutes|
|Pre-requisite Concepts||Conduction, convection, density, heat properties, temperature|
|Course||Earth & Space Science|
|Type of Tutorial||Concept Development|
|Key Vocabulary||air, anemometer, breeze|