Mayonnaise Jar Greenhouse
- 1 glass jar with lid (a square jar works best)
- 2 small thermometers
- 1 short piece of string (to hang the thermometer in the bottle)
- bright desk lamp or sunny window
- black paper (optional)
Link with climate change
The greenhouse effect is a natural phenomenon that allows life on Earth. Without this greenhouse effect, temperature at this surface of the Earth would be -18oC.
The atmosphere, which circles the Earth, traps heat from the sun. Certain gases in the atmosphere are called greenhouse gases. Greenhouse gases allow sunlight to pass through the Earth's surface, and increase temperatures. As the heat rises, some of it is trapped by the greenhouse gases. This allows life on Earth because it increases average global temperatures to 15oC.
Humans have increased the concentration of greenhouse gases in the atmosphere with different activities: burning of coal, oil, natural gas, deforestation, old landfills and other activities. This increase in greenhouse gases thickens the layer and traps more solar radiations. The temperature on the surface of the Earth increases.
Description of the activity :
- attach 1 thermometer to the inside of the lid so it can be seen from the exterior of the jar. The thermometer can touch the bottom of the jar;
- add a few drops of water in the jar and close the lid with the thermometer inside;
- place the jar in a sunny window or beside a desk lamp. Next to it place the second thermometer;
- record the temperatures of both thermometers every 10 minutes for one hour;
- use the data to discuss the greenhouse effect or to explain how to draw a graph;
- explain to students that the jar traps heat like the greenhouse gases. However, the Earth's atmosphere is not a solid barrier which stops hot air from leaving, as a glass jar does.