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<p>In recent times we have often received news such as about melting glaciers, sudden and torrential rain, storms, increased atmospheric temperatures, and forest fires. We have also observed some of these phenomena in our immediate vicinity. There is a frequently used expression among the public, 'the seasons are shifting'.&#160;</p>
<p>Students have asked the reasons why these changes have been occurring and what about changes between the past and present. In order to understand these changes we all know that they need to understand global warming in the first place. To help them with this as an science teacher I have guided them to be capable of using experimental methods within project-based learning approaches. First they did preliminary literature surveys and then they designed an experiment. In the experiment, they tested the hypothesis that the water inside the bell JAR, which is coated with black cardboard, heats up more than the transparent one. In this way they&#160;began to investigate climate change due to greenhouse gases.&#160;</p>
<p>In the experiment, two bell glasses were used to represent the atmosphere layers. One was intermittently covered with pieces cut out of black cardboard. Black cardboard was used to represent the greenhouse gas due since the black colour absorbs light. Two beakers of the same size were used, filled with water. A thermometer was placed inside and bell jars were turned upside down and put over the beakers. The two thermometers were used to measure the water temperature inside the beakers.&#160;</p>
<p>The first apparatus is the control group (inside uncovered). The second apparatus is the experimental group (covered with independent black cardboard). In the experimental and observation stage, the independent variable is the bell jar; the dependent variable is the water temperature. The constant variables are the size of the jar, the size of the beaker, the amount of water and the ambient conditions.&#160;</p>
<p>Having set up the apparatus, the initial temperature of water was measured and recorded. Students carried out the experiment on a sunny day by placing the apparatus in a sun-covered field. They recorded the data in the tables they completed periodically. Then they shared the results with participants at the science festival.&#160;</p>
<p>In this way they began to investigate the impact of greenhouse gases on climate change.</p>
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