We are only beginning to understand why climate changes, but we know that the main causes are natural. Changes in the amount of energy released by the sun are one cause. Clouds are another cause. Humans also cause climate to change. That is because factories and cars produce more heat, and also because asphalt and cement absorb heat better than plants and trees.
Cities also produce a lot of air pollution that contributes to climate change.
Humans also cause climate change in rural areas when they clear forests and plant crops. Different colored crops can change the amount of energy that is absorbed by vegetation. All this human activity on the surface of our planet can cause climate change. The list below presents some of the reasons people have for being concerned about global warming. Then work with three or four other students and try to reach a group consensus on how to rank the statements.