Water in the Atmosphere 18.1

Precipitation

• Any form of water that falls from a cloud.

Latent Heat • The energy absorbed or released during

a change in state.

Evaporation

• The process of converting a liquid to a gas.

Condensation

• The change of state from a gas to a liquid.

Sublimation • The conversion of a solid directly to a gas

without passing through the liquid state.

Deposition • The process by which an agent of erosion

loses energy and drops the sediment it is carrying; also the process by which water vapor is changed directly to a solid without passing through the liquid state.

Humidity

• A general term referring to water vapor in the air but not to liquid droplets of fog, cloud, or rain.

Saturated• The state of air that contains the maximum

quantity of water vapor that it can hold at any given temperature and pressure.

Relative Humidity

• The ratio of the air’s water-vapor content to its water-vapor capacity.

Dew Point • The temperature to which air has to be cooled

in order to reach saturation.

Hygrometer

• An instrument designed to measure relative humidity.

Key Concept

• When it comes to understanding atmospheric processes, water vapor is the most important gas in the atmosphere.

Key Concept

• The process of changing state requires that energy is transferred in the form of heat.

Key Concept

• When saturated, warm air contains more water vapor than saturated cold air.