科学素养与生活应用·英语30篇（2）

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雾为何在暖空气接触冷地面时形成？

Fog forms when moist air cools rapidly near the ground overnight.
As temperatures drop, water vapor condenses into tiny liquid droplets suspended in air.
This process requires high humidity and a surface that loses heat quickly after sunset.
Radiation fog is most common in calm, clear nights with little wind or cloud cover.
Unlike clouds, fog develops at ground level where cooling is strongest and most direct.
Dew point temperature must be reached for condensation to begin visibly.
Urban areas often see less radiation fog due to heat retention from buildings and roads.
Farmers monitor fog forecasts carefully because it can delay morning fieldwork safely.
Fog usually lifts by mid-morning as sunlight warms the surface and evaporates droplets.
Its density depends on moisture content, cooling rate, and atmospheric stability.