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Water use and the water cycle
Water use and the water cycle

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Monday, 8 Aug 2022, 05:22
Site: Open Learning
Course: Water use and the water cycle (S278_12)
Glossary: S278_12 Glossary
P

Potential evapotranspiration

The maximum evapotranspiration that could take place given an unlimited supply of moisture.

Precipitation

The process involved or the water that is transferred in solid or liquid form from the atmosphere to the Earth’s surface.
R

Reservoir

When used in connection with the water cycle, this is a part of the hydrosphere that stores water temporarily. Also a means of artificial water storage.

Residence time

The average time that water stays in a reservoir before moving to another reservoir; e.g. the average time that a water molecule spends in the atmosphere before falling to the ground as rain or snow.

S

Saline intrusion

A wedge of seawater under fresh groundwater near a coastline, caused by excessive groundwater extraction.

Saline water

Surface water with a high TDS; this is seawater in the oceans and some lakes.

Salinisation

The accumulation of salts in the soil that may occur with irrigated agriculture.
T

Transpiration

The process by which plants draw water from the soil and transfer it to their leaves, from which it evaporates through pores in the leaf system.
W

Water cycle

The natural cycle by which water is circulated between the Earth’s surface (on or under it) and the atmosphere. In essence, water is evaporated from the oceans, forms clouds, is precipitated on land as rain, hail or snow, and then flows in rivers, glaciers or underground to the sea, where it is evaporated again.