Grade Level: 6th; Type: Environmental
The goal of this project is to create radiation fog to see how it forms and how environmental elements affect it. Studying fog in a bottle provides opportunities to test hypotheses such as whether light can shine through the thick layer of air.
- How does fog form?
- How does wind affect fog?
- How does light work in fog?
Fog is a cloud that forms just above the ground. There are two types of fog: advection and radiation. Advection fog occurs on the Pacific coast when warm, moist air blows over cold water, forming a low-hanging cloud that gets blown inland. The heavy, wet cloud provides water for coastal plants. Radiation or ground fog is common everywhere, especially in autumn. A thin layer of warm, moist air forms near the ground, and cooler, dry air lays atop it. As the temperature drops, condensation occurs. Clear nights with a slight breeze offer the optimum conditions for radiation fog.
- At least two bottles with narrow necks to hold ice cubes
- Hot and cool water
- A ruler
- Additional supplies: food coloring, a fan, etc
- Fill one bottle with very hot water.
- Fill the other bottle with an inch of cool water.
- After several minutes, empty the hot water and replace with one inch of hot water.
- Place an ice cube in the neck of each bottle.
- Record what happens in each bottle.
- Add food coloring to the inch of hot water and see if the fog colors.
- Blow a fan over the fog, increasing the speed to judge the affect of a slight breeze versus a brisk wind.
- Shine several flashlights through the fog to see what happens when light hits the wet, heavy cloud.
A simple logbook records the effects of creating fog and any conditions applied to it:
Initial Creation of Fog
30 sec. after inserting ice cube, wisps of smoke form just above the water’s surface. It grows until 2:30 when the cloud settles.
40 sec. after the ice cube was put in the neck of the bottle, a small cloud formed above the water and grew until 2:45.
Fan on Low Setting
Terms/Concepts: Advection fog; Radiation fog
- Fog and Mist, Elizabeth Miles (2005).
- Weather, DK Publishing (2005).