Unit 3: The hydrosphere                                                    1   2   3   4   5

2. The water cycle

The water cycle is the movement of water throughout the Earth. Water is continuously changing its location on the Earth and its physical state, but the total amount of water remains constant.

The water cycle consists of the following processes:

- Evaporation.

Liquid water changes to a gas (water vapour). It evaporates.

Water passes from the hydrosphere to the atmosphere.

- Transpiration.

Water evaporates into the atmosphere from living beings, mainly plants.

- Condensation.

Water vapour changes to liquid, forming clouds and dew. It condenses.

- Precipitation.

Water returns to the Earth’s surface as rain, snow or hail.

- Surface run-off.

Surface water moves across the land and it forms rivers and streams, and finally flows into the sea

- Infiltration.

Surface water filters in part into the ground. It forms groundwater.

2.1. Indicate what process allows the pass of the water:

a. From rivers to sea

b. From living beings to atmosphere

c. From Earth’s surface to ground.

d. From sea to atmosphere

e. From clouds to Earth’s surface

2.2. Listen and indicate which stage of the water cycle is described.