Convection Box (Lupe Anaya)

Author

Lupe Anaya

Bell Gardens High School

Principles

• Convection currents

• Global winds

• Mantle convection

Standards

Materials needed

1. convection box

2. candle

3. lighter

4. paper or incense

5. dark background

Procedure

1. Put the candle inside the box under one of the tubes and light it.

2. Close the glass sliding door.

3. Light up a piece of paper and reduce the flame so as to only have the smoke.

4. Place the smoking paper near the top of the opposite tube and observe the direction the smoke flows.

Explanation

The candle warms up the air inside the box. As this air warms up it becomes less dense than the surrounding air and rises out of the tube. The cooler air surrounding the opposite tube is denser so it sinks down the tube. As this air rushes in, it pushes the warm air out. The air warms up again and the process starts again. The convection current will continue as long as there is a heating source.

Questions

1. How does solar energy influence weather and climate? Weather is driven by the circulation of air by convection currents. Solar radiation heats up the Earth's surface and the heated air picks up moisture and rises. This rising air cools, the moisture condenses and forms clouds and precipitation. The cool, drying air starts to sink and compress. As it compresses and sinks it becomes dry, warm air that will be heated up again and the cycle continues.

2. How do Hadley, Ferrel, and polar cells help to determine long-term climate patterns and the location on biomes? These large scale convection currents distribute distribute heat and material throughout the globe and determine the humid and arid climate patterns. For example, the warm air near the equator rises, expands and cools leading to moisture condensing. This explains the wet climate in the tropical regions. The air travels towards the poles and since it's cooler sinks at the 30 degree latitude, north and south. Since this cool air lost moisture in the tropics, the 30 degrees latitude regions are arid. This first cell is the Hadley Cell, but this pattern of warm air rising and cool air sinking continues in both hemispheres forming the Ferrel and polar cells and creating the moist and dry climates.

3. What are some of the pollutants in the Arctic and how did they get there? Air pollution in the arctic consists of dust, sulfates, ammonium, nitrate and black carbon, nitrogen oxides, and other organic compounds. Most of these pollutants were formed from sources around the world were carried to the Arctic by the wind and ocean currents.

Everyday examples of the principles illustrated

Convection and the unequal heating of the earth leads to the formation of global wind currents across the world.

Convection currents in the mantle cause the continental plates to move.

Photos

Movies

References

Oceans North: Protecting Life in the Arctic