Scaffolded notes
Build the idea
A strong model shows relationships
A useful system model names reservoirs, labels processes on arrows, identifies state changes, and shows where solar energy or gravity drives movement. It should display several possible pathways rather than one fixed loop.
Models explain and predict
A model should help answer a question. For example, increasing solar heating may increase evaporation if water is available. Cooling moist air to its dew point increases condensation. Steep slopes and saturated soil may increase runoff.
Every model has limits
A diagram may not show rate, scale, storage time, groundwater complexity, or changing human influences. Naming limitations is a strength because it shows what evidence would be needed to improve the model.
Stop and explain
Check your thinking
1. Where should solar energy appear in the model?
Possible response: At processes such as evaporation and transpiration, and as a driver of heating.
2. Where should gravity appear?
Possible response: At precipitation, runoff, infiltration/percolation, and downhill groundwater movement.
Interactive challenge
Try the science
Which addition most improves a basic water-cycle diagram as an explanatory model?
Before you leave
Exit ticket
Name one required feature and one limitation of your model.