This is a short NASA video on the water cycle. The video shows the importance of the water cycle to nearly every natural process on Earth and illustrates how tightly coupled the water cycle is to climate.

Students model the effect of greenhouse gases on Earth's atmosphere. They find that greenhouse gases, such as carbon dioxide and methane, are uniquely shaped to catch and pass on infrared radiation, and so they are responsible for the warmth we enjoy on Earth. The children discuss how the addition of greenhouse gases by human activities leads to further warming and what steps we can take to slow it.