Scientists think that continual climate changes can reach critical points when there will be no possibilty of reversing changes, one being the 2 degrees Celcius rise of global temperature. Climatologists predict that within several years global warming can cause change of seasons in Poland – from current four seasons to two dominant periods: cold rainy season and warm dry. Unfortunately, every place on our planet will be affected.
Watch with the children a short film by Adam Wajrak about the Białowieża Forest and its transformations. Ask the children to carefully listen to the journalist`s story and in the end enumerate all the endangered animals and plants species which were mentioned by Adam Wajrak during the film.
After watching the film, it`s time for an experiment which will demonstrate to children why our climate is getting warmer.
MATERIALS
- 2 jars and a cap or 2 boxes and a lid
- Two thermometers
- A sunny day
Experiment 1
Put a thermometer into one box and close it tightly, then put the other thermometer into the other box, but leave this box open. Leave the boxes for a few hours in a sunny spot. If you do this experiment during the winter, when sunny days are a rarity, put the boxes under the radiator, the effect will be similar. Now open the box and check the temperature. Compare it with the temperature in the open box. In which jar/box is the temperature higher and why? Let the children guess.
Experiment 2
If the children don`t have any ideas, conduct an additional experiment. Get a big blanket and suggest that the children stand close to each other so that all of them will fit in it wrapped up. Let them stay like that for a few minutes. After getting out from under the blanket, ask the children whether it was warm. And when it was it warmer: when they were standing together under the blanket or when they where sitting separately without a cover?
This phenomenon is analogous to what happens with the air in the boxes. When the box is closed, the air inside gets warm, because sun rays can get inside, but the warmth cannot get outside and that`s why the temperature still rises. The same thing happens to our planet. Greenhouse gases cover the Earth like a blanket. The sun rays get through that layer, but warm air can`t be cooled down, because it`s heavier than greenhouse gases, so it gradually gets warmer, causing the climate change. That`s why it`s so important to reduce the emission/prodcution of greenhouse gases.
