Water Supply, Use, and Shortages

Vocabulary flashcards covering key terms, concepts, and case study details on global water supplies, sector usage, water shortages, and management strategies.

Freshwater

Water containing low concentrations of dissolved salts, accounting for only $2.5\%$ of all water on Earth.

Global Freshwater Distribution

The proportion of Earth's freshwater stored in different reservoirs: $68.7\%$ in glaciers and ice sheets, $30\%$ in groundwater, $0.8\%$ in permafrost, and $0.4\%$ in surface and atmospheric water.

Aquifer

An underground layer of permeable rock that is fully saturated with water after water has filtered through soil and rocks.

Surface Water

Water that is stored above ground in natural and artificial features such as lakes, reservoirs, and rivers.

Desalination

The process of removing salt from seawater to make it suitable for domestic, agricultural, and industrial uses.

Rainwater Harvesting

The practice of collecting and storing water that falls directly as precipitation for future use.

Over-abstraction

The overuse or excessive extraction of water from aquifers at a rate faster than it can naturally recharge through precipitation.

Water Stress

A condition that occurs when the available supply of water in a region falls below $1700\,\text{m}^3$ per person per year.

Water Scarcity

A condition that occurs when the available supply of water in a region falls below $1000\,\text{m}^3$ per person per year.

Physical Water Scarcity

A situation where physical access to water is limited by natural climate conditions and low precipitation levels.

Economic Water Scarcity

A situation where a population lacks the financial resources or infrastructure to extract and utilize available water resources.

Potable Water

Clean drinking water that is safe for human consumption.

Water Use in LEDCs

The sector breakdown of water consumption in Less Economically Developed Countries, comprising $82\%$ agriculture, $10\%$ industry, and $8\%$ domestic use.

Drip Irrigation

An efficient irrigation system that delivers water directly to the roots of plants, minimizing evaporation and water loss.

Grey Water

Recycled household wastewater that is reused for non-potable purposes such as washing cars and watering plants.

Tagus-Segura Project

A $286\,\text{km}$ pipeline completed in 1978 that connects four Spanish river basins (Tagus, Jucar, Segura, and Guadiana) to divert water to southeast Spain.

Ebro Project

A proposed 2001 water transfer scheme in Spain meant to divert water from the River Ebro, which was abandoned due to high costs and environmental risks to the Ebro Delta.

Water Surplus and Deficit Map

A global distribution map illustrating water availability, where dark blue areas represent the greatest water surplus and dark orange areas represent the greatest water deficit.