The Greenhouse Effect
Appropriate for Grades (5-8)
Developed by: Andrew Leech
Students should be able to: * Understand the properties of greenhouse gases * Understand the role that the greenhouse effect plays in global warming * Understand the changes that must take place to make earth sustainable
The Green House Effect
Have you ever walked through a green house in late January? The temperature on the outside may have been quite cold but the temperature on the inside might have felt almost balmy!
This is not because of a giant furnace located in the back of the green house, but because of the green house effect. When rays from the sun travel through the glass, it strikes all materials within the greenhouse. Because of this, the objects will heat up as does everything that comes in contact with the suns infrared rays (heat). These rays generally bounce back towards where they came from unless there is a barrier to keep them in. Yes that’s right, a barrier such as glass!
The Green House Effect
Once the infrared rays bounce off of the objects contained in the green house, some of the rays get trapped inside of the greenhouse because of the glass. The rays then bounce off of the glass and back towards all of the objects in the green house. As the rays of infrared radiation (found in sunlight) bounce all over the greenhouse, the greenhouse heats up. How is the earth like a giant green house?
What would represent the glass?
The Earth as a Greenhouse
If you said that the glass of earth’s “greenhouse” would be our atmosphere, you would be CORRECT!!!!
Is the greenhouse effect a bad thing?
The atmosphere not only protects us from harmful radiation but it also works as a greenhouse to keep our planet inhabitable. If it were not for our atmosphere and the green house effect, the average temperature of earth would be around 18 degrees Centigrade. The earth’s atmosphere contains several key greenhouse gases.
Green House Gases
What are green house gases?
Not all gases are greenhouse gases! A green house gas is any gas that is able to “trap” or hold in heat . These are the gases in the atmosphere which act in the same way as the glass does in a greenhouse. Several greenhouse gases are produced by the earth naturally such as Carbondioxide, Methane (natural gas) and Nitrous Oxide. These gases are vital to maintaining a climate warm enough to support the diversity of life on our planet.
Greenhouse Gases
The following pie chart displays the percent of each gas which plays a role in the greenhouse effect.
Greenhouse Effect
Twenty-four percent of all the greenhouse gases come from man made products such as the ones produced from coolants, aerosol propellants and solvents. These are known as chlorophlorocarbons or CFC’s. Unlike the natural greenhouse gases, the CFC’s come from humanbeings.
Global Warming
As previously mentioned, the greenhouse effect is necessary for us to sustain life, without it, it would be too cold. However, when the atmosphere becomes saturated with greenhouse gases, global warming could occur. The extra greenhouse gases would be equivalent to placing an extra wooly blanket around the entire planet. Global Warming- The apparent overall warming trend of the earth’s atmosphere
What are some possible effects of global warming?
Possible Effects of Global Warming
Some scientist predict that if the temperatures of earth get to warm, the polar ice caps could potentially melt and raise the sea level. If this were to occur, many coastal regions could be flooded. Other scientist believe that with a warming trend, entire climates could be altered. For example, the mid-west could become almost desert-like. Some diseases which are only found near the equator due to the warm temperatures could migrate further north and south of the equator.
Conclusion
The greenhouse effect is necessary for our planet to be habitable, however, it is also necessary that we find a way to control it so that we do not have to deal with the issue of global warming in the coming years.
See if you can come up with a few suggestions to help prevent global warming.
Sources
WWW.SUTON.AC.UK