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WEATHER
Lesson 4 - Page 2

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Humidity describes the amount of water vapor in the air. Warm air can hold more water vapor than cold water. Tropical areas are noted for their high relative humidity. On a humid day, people with naturally curly hair experience the "frizzies" caused by a stretching of the hair.

Clouds, fog, and dew are formed when condensation occurs. The air must be saturated with water vapor and tiny bits of particulate matter known as condensation nuclei must be present. These nuclei serve as surfaces for the condensation of water vapor.

In cloud formation the process is rapid and results in the formation of billions of tiny water droplet. They are so fine that they remain suspended in air. Difference in heat within clouds can cause convection which allows the small droplets to move within the cloud. This is when it gets interesting. The droplets can freeze as it gets colder and then in warmer areas, they melt. All these different conditions cause different types of weather.


The frizzies

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