A land breeze is a type of wind that blows from the land to the ocean.
When there is a temperature difference between the land surface and the ocean, winds will move offshore.
Although commonly associated with ocean shorelines, land breezes can also be experienced near any large body of water such as a lake.
Land breezes usually occur at night because during the day the sun will heat land surfaces, but only to a depth of a few inches.
At night, water will retain more of its heat than land surfaces because water has a high heat capacity.
Furthermore, the temperature of the land cools quickly without the insolation from the sun.
Heat is rapidly re-radiated back to the surrounding air causing the water along the shore to then be warmer than the coastal land, creating a net movement of air from the land surfaces towards the ocean.
The movement of the wind is a result of differences in air pressure over the land and the ocean.
Warm air is less dense and rises, therefore cool air is more dense and sinks.
As the temperature of the land surfaces cool, the warm air rises and creates a small area of high pressure near the land surface.
Since winds blow from areas of high to low pressure, the net movement of wind is from the shore to the water as shown in the image to the right.
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