Food & Climate 

Basics

Worksheet: Climate change effects

 Sheet 2: Experiment on greenhouse effect

The picture shows you in a simplified way how the greenhouse effect intensifies by the increase of CO₂ in the atmosphere.

The greenhouse effect, picture drawn by Julia Heres

Explanations of the picture:

1. Burning down long living forests for landuse changes adds carbon dioxide to the air.
2. Exhaust fumes contain large amounts of CO₂.
3. CO₂ spreads within the atmosphere.
4. Sun radiation permeates the atmosphere.
5. The sun's radiation heats up the ground and ...
6. ... the warm surface emits long wave heat radition (infrared light).
7. This thermal radiation is taken up by greenhouse gases as CO₂ an partially sent back to the surface.
8. The atmospheric layers next to the ground become warmer.

The picture shows you in a simplified way how the greenhouse effect intensifies by the increase of CO₂ in the atmosphere.
Originally, the greenhouse effect is a very normal process. Without this effect we would freeze to death.
But by the rise of the CO₂ concentration in the lower atmosphere the long wave rays are sent back to earth.
Consequently the temperature on earth rises.

EXPERIMENT:

You can simulate the greenhouse effect in a little experiment.

What you need:

- Box

- Lantern slide, which can cover the box

- 2 electric thermometers

- a sunny day

Instruction:

Put the box outside in the sunshine on a sunny day. Place one thermometer inside the box and the other one next to the box. Now cover the box with the lantern slide. After 15 minutes compare the temperatures of both thermometers.

1. temperature inside the box                     2. temperature outside the box
(picture taken by Sarah Ancot)

CAN YOU ANSWER THE FOLLOWING QUESTIONS?

1. Which thermometer shows a higher temperature and why?
 
2. Have a close look at the graphic once more and complete the following text.

……………………… - frequent sun rays interpenetrate the lantern slide.

At the bottom of the box they are …………………………….

Thereby the rays are converted into ………………………………..

These rays are  …………………………. by the lantern slide.

Thereby the thermal radiation remains within the box and ……………… the air.

3. Consider which processes are responsible that more CO2 reaches the atmosphere.

How can  some of these processes be prevented or reduced?

Further links:

www.treibhauseffekt.com

www.uni-koblenz.de/~odseich/klima/

 

About this page:

- Author: S. Ancot - University of Nürnberg - Germany
- scientific reviewing:
- educational reviewing: Dr. Schrettenbrunner / J. Heres
- last update: 29.10.03