HYDROLOGIC CYCLE - Civil Engineering Lecture Notes (3rd Year)

Vocabulary flashcards covering key concepts of the hydrologic cycle from the lecture notes.

Hydrologic Cycle

The continuous movement of water among the atmosphere, land, and sea, including evaporation, transport in the atmosphere, precipitation, and storage/movement among water reservoirs.

Humidity

The amount of water vapor in the atmosphere; relative humidity indicates how moist the air is.

Precipitation

Any form of water that falls from the atmosphere to the Earth's surface (rain, snow, sleet, hail).

Runoff

Water from rainfall or snow that flows over the land into streams, typically not affected by artificial diversions.

Interception

The process by which precipitation is intercepted by vegetation or surface cover and does not immediately reach the ground.

Interception storage

Water temporarily stored on vegetation or surfaces due to interception, before it evaporates or infiltrates.

Detention storage

Water temporarily stored in surface pools or depressions; may evaporate or infiltrate.

Infiltration

Movement of water from the ground surface into the soil, governed by surface conditions and soil porosity/permeability.

Percolation

Downward movement of water through soil layers by gravity and capillary forces, contributing to groundwater recharge.

Capillary rise

Upward movement of water in soil due to capillary action.

Groundwater

Water stored underground in aquifers; can discharge to streams or be pumped for use.

Groundwater recharge

The process by which infiltrated water percolates downward to replenish groundwater reservoirs.

Surface storage

Water stored on the surface (ponds, lakes, wetlands) or in the soil moisture reservoir; can evaporate or infiltrate.

Evaporation

Phase change of liquid water to water vapor; requires heat; energy about 600 calories per gram.

Transpiration

Biological release of water vapor from plants, moving water from roots to leaves.

Evapotranspiration

Combined evaporation from surfaces and transpiration from vegetation returning water to the atmosphere.

Condensation

Phase change of water vapor to liquid, forming dew, fog, or clouds; occurs on particles like sea salts and atmospheric ions.

Clouds

Visible masses of condensed water vapor in the atmosphere formed around particles.

Dew

Water droplets formed by condensation on surfaces.

Fog

Low-lying clouds formed when water vapor condenses in the air near the ground.

Energy for evaporation

The energy required to convert liquid water to vapor; approximately 600 calories per gram.

Flow and Store

Two concepts of the water cycle: Flow refers to movement between stores; Store refers to reservoirs that hold water.

Freshwater stores

Freshwater is stored in ice sheets/glaciers, rivers, reservoirs, soils, wetlands, vegetation, groundwater, and aquifers; oceans contain most of Earth’s water.

Ocean precipitation fate

Precipitation that falls directly into the ocean becomes part of the surface ocean and can be moved into currents by waves and wind.