Another kind of model is useful in explaining concepts, or ideas. A conceptual model can illustrate the water cycle, where evaporation and transpiration lead to the formation of clouds and then to precipitation in the form of rain, sleet, or snow.

Conceptual models can be diagrams. A food web is an example of a concept drawn as a flow chart. It illustrates the interconnected food chains in a community of plants and animals.

Each link in the food chain depends on another plant or animal for the survival of its specieas.

Conceptual models can even be verbal descriptions or drawings of how something works. It's easier to explain why we have different seasons when we can see how the tilt of the Earth changes over the course of a year. In June, July, and August, when the Northern Hemisphere tilts toward the Sun, it experiences summer as it receives direct rays that bring more warmth. At the same time, the Southern Hemisphere, tilted away from the Sun and receiving indirect rays, is experiencing winter.

The Seasons ON Earth

Earths axis of rotation 23.5°