HomeIB ESSTopic 4.1

Water systems

Topic 4.1 introduces the global hydrological cycle, freshwater systems, and ocean circulation patterns. Students study water storage, transfers between reservoirs, and how human activities affect the natural water cycle — foundational knowledge for the water unit in IB ESS.

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IB ESS · Topic 4.1

Sub-topics in Topic 4.1

4.1.1What drives the water cycle 4.1.2The water cycle as a system 4.1.3Where the world's water is stored 4.1.4Flows in the water cycle 4.1.5How human activities change water flows 4.1.6Water budgets and sustainable harvesting