Various fogs are essentially clouds that form at the earth's surface, produced by temperature differences and moisture in the air. As warm, moisture-laden air cools, the amount of moisture that air can contain decreases. Warm air can hold more water vapor than cold air. So if the air is cooled sufficiently it will reach the dew point, at which the moisture begins to gather together out of the air and form water drops, creating fog.
- ①To explain how fog is formed
- ②To describe various types of fog
- ③To show when warm air affects the fog
- ④To point out why moisture works in the air
정답 ①
출처: 인사혁신처 공개 기출(공공데이터포털, 이용허락 제한 없음)