Water Cycle — Prelims Strategy

Prelims Strategy

Learn the stores and transfers as a network. For each process, state its starting store, ending store and any phase change. This distinguishes evaporation from boiling, condensation from precipitation and infiltration from groundwater recharge. Read diagram arrows according to their legend rather than assuming one fixed route.

For water-balance questions, write the boundary and period and keep all terms in compatible units. Use storage change as the difference between specified inputs and outputs. Do not label an unexplained real-world residual as recharge without considering missing exchanges or measurement uncertainty.

When evaluating a human intervention, identify the pathway it changes. Paving can affect runoff and infiltration; pumping can alter storage and hydraulic relationships. Avoid universal numerical claims about the response. During review, explain why each incorrect option skips an intermediate store or confuses a rate with a quantity. A useful self-test asks where infiltrated water can go before it ever reaches an aquifer.