As we know, global warming is becoming a global issue. It alarms the whole world to protect the destroyed environment. Global warming is a "natural phenomenon". In general, we know that the origin of global warming is the emission of carbon dioxide. It was verified that the relationship between carbon dioxide and temperature: when there is more carbon dioxide the temperature gets warmer. This topic should be discussed under current situation to advocate people concerning with this severe environmental issue. Meanwhile, people should consider how to reduce the emission of carbon dioxide and take some actions to stop global warming.
What is global warming? Global warming is the increase in the average temperature of Earth's near-surface air and oceans since the mid-20th century and its projected continuation. According to the 2007 Fourth Assessment Report by the Intergovernmental Panel on Climate Change, global surface temperature increased 0.74 ± 0.18 °C (1.33 ± 0.32 °F) during the 20th century. In nearly 100 years, the average global temperature goes through four fluctuations: cold, warm, cold again, and warm again. After 1980s, the temperature was ascending obviously.
We can see the changes through an experiment. Have students mix 4 tsp. of salt into an 8-oz. glass of tap water from the fridge and add it into a wide-mouthed, 1-quart-volume glass jar. Instruct youngsters to take a second 8-oz. glass of room temperature water and stir in 4 tsp. of salt and 1/2 a medicine dropper of red food coloring. Children should then hold a desert spoon over the mouth of the refrigerated water and slowly pour the red room temperature water into the spoon so it spills over and mixes with the cold water. Youngsters should observe the outcome carefully, as the colder water is layered below the warmer water. Students should repeat this experiment with different temperatures and salinities of water to see how they can explain how global warming can...
Please join StudyMode to read the full document