Chapter 6 Moisture, Clouds, and Precipitation Review

Question and answer flashcards covering key terms and concepts from Chapter 6 notes, including water phase changes, atmospheric moisture, lifting mechanisms, atmospheric stability, cloud types, and fog formation.

What are the three physical states or qualities of water mentioned in the notes?

Solid, liquid, and gas.

What is evaporation?

The process of converting a liquid to a gas, also known as water vapor.

What is condensation?

The process that occurs when water vapor changes to the liquid state.

How is melting described in terms of molecular movement?

When the rate of molecular movement increases sufficiently, the bonds between the water molecules begin to break, resulting in melting.

What is freezing?

The conversion of a liquid into a solid when the temperature falls below a substance's freezing point.

What is sublimation?

The conversion of a solid directly to a gas, without passing through the liquid state.

What is deposition?

The reverse process of sublimation; the conversion of a vapor directly to a solid.

What is humidity?

The amount of water vapor in the air.

What is the mixing ratio?

The mass of water vapor in a unit of air compared to the remaining mass of dry air.

What is relative humidity?

The ratio of the air's actual water-vapor content to the amount of water vapor required for saturation at that temperature and pressure.

What is the dew point?

The temperature at which water vapor begins to condense.

What are adiabatic temperature changes?

Temperature changes in which heat energy is neither added nor subtracted.

What is the Environmental Lapse Rate and how is it determined?

The rate at which the temperature of the atmosphere above a parcel changes with height; determined from observations made by radiosondes and aircraft.

What is orographic lifting?

A process that occurs when elevated terrain, such as a mountain range, acts as a barrier to the flow of air.

What is frontal wedging?

A process when the cooler denser air mass in a front acts as a barrier over which the warmer, less-dense air rises, instead of mixing.

What is convergence (also known as lifting)?

When the wind pattern near Earth's surface is such that more air is entering an area than is leaving.

What is localized convective lifting?

The phenomenon that produces rising thermals.

When does atmospheric stability occur?

When the environmental lapse rate is less than the wet adiabatic rate.

How are absolute instability and conditional instability defined?

Absolute instability occurs when the environmental lapse rate is greater than the dry adiabatic rate; conditional instability occurs when moist air has an environmental lapse rate between the dry and wet adiabatic rates.

What are condensation nuclei?

Tiny bits of particulate matter that serve as surfaces for water-vapor condensation when condensation occurs above the ground.

What are the characteristics of cirrus clouds?

Clouds that are high, white, and thin; form delicate veil-like patches or wisplike strands and often have a feathery appearance.

What are the characteristics of cumulus clouds?

Globular cloud masses described as cottonlike in appearance, with a flat base, appearing as domes or towers, forming where there is some convection and rising air.

What are stratus clouds?

Clouds that consist of sheets or layers that cover much or all of the sky.

What altitude range defines alto- clouds?

Middle range ($6,500\text{--}20,000\text{ ft.}$).

What ten cloud names are listed in the Chapter 6 notes?

Cirrus, Cirrocumulus, Cirrostratus, Altocumulus, Altostratus, Stratocumulus, Stratus, Nimbostratus, Cumulus, Cumulonimbus.

How does advection fog form?

When warm, moist air blows over a cold surface, it becomes chilled by contact with the cold surface below; if cooling is sufficient, this fog appears.

How does radiation fog form?

Results when ground cooled by radiation cools the overlying layer of air.

How does upslope fog form?

Formed by relatively humid air moving up a gradually sloping landform, or in some cases, up the slopes of a mountain.