Question

The diagram below represents the circulation of air above Earth's surface at a coastal location during the day and at night.

This local air movement is best described as an example of
1.
conduction between Earth's surface and the atmosphere above it
2.
condensation of water vapor during the day, and evaporation of water during the night
3.
convection resulting from temperature and pressure differences above land and water
4.
greater radiation from the warmer ocean during the day and from the warmer land at night
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Answer 1

3. convection resulting from temperature and pressure differences above land and water

Step-by-step explanation:

Due to the the difference between the ability of land and to water to absorb and radiate heat energy, the land gets heated up by the sun more quickly than water during the hot afternoons. As a result, the air above the land surface gets heated up more quickly than that above water. Warm air being less dense than cold air will rise above to atmosphere creating a low pressure area on land. On the other hand, air above water is not heated up as quickly, thus the dense cooler air over water will rush in and replace the warm air that has risen above the land surface.

At night, the land cools off more easily than water, hence the air above the land surface is cooler. On the other, water does not lose heat as quickly as the land, hence the air above the water surface is warmer than that over land. Warm air over the water surface will rise above, while colder air from land will replace it.