ESC1000 Chapter 17 Moisture, Clouds and Precipitation

58 terms by thumpaholden 

Create a new folder

Advertisement Upgrade to remove ads

Melting

Substance solid transforms to liquid. A cooling process

Cooling process

Is melting a heating or cooling process?

Freezing

liquid transforms to solid. A heating process.

Heating process

Is freezing a heating or cooling process?

Evaporation

liquid transforms to vapour. A cooling process

Condensation

Vapour transforms to liquid. A heating process.

Sublimation

A solid transforms to a gas, skipping the liquid phase. A cooling process.

Deposition

A gas transforms to a solid. A heating process.

Humidity

the amount of water vapor in air.

Higher

When temperature is higher, the amount of water vapor air can hold is _______

Lower

When temperature is lower, the amount of water vapor air can hold is _______.

Unsaturated

When a given parcel of air is holding less water than it can actually hold it is___________.

Saturated

When a given parcel of air is holding all the water vapor it can hold, it is _________.

Mixing ratio

specific humidity

Specific humidity

Ratio of the amount of water vapour in air by weight, compared to the mass of air it is in. Not affected by temperature.

Absolute humidity

Ratio of the amount of water vapour in air by volume, compared to the volume of air it is in. Not affected by temperature.

Relative humidity

Ratio of the amount of water vapour in air compared to the amount needed to saturate the air at the same temperature. Given as a percentage. Is strongly affected by temperature.

Relative humidity

how much water the air is holding relative to the amount is can potentially hold, its capacity. Is strongly affected by temperature.

Increases

What happens to relative humidity when temperature increases?

Decreases

What happens to the capacity of air to hold water vapour when temperature decreases?

Increases

What happens to relative humidity when the water vapour content of the air stays the same, but the temperature drops?

Dew point

The temperature that a parcel of unsaturated air would have to fall to, in order to become saturated. Given as a temperature.

Hygrometer

A device to measure humidity

Sling psychrometer

a type of hygrometer.

Adiabatic temperature change

When a gas changes temperature because of a pressure change (either expansion or compression).

Orographic lifting

When air is forced up and over mountains

Frontal wedging

weather process where a body of cold air meets hot air, and the hot air is forced up and over the cold air, it expands, cools, condensation occurs and clouds form.

Convective lifting

weather process where the sun heats the land surface, which heats the adjacent air, and then the heated air rises.

Thermal

another name for convective lifting.

Convergence

weather process where wind (with air of similar temperatures) from two directions meet and the only way for the air to go is up.

Cirrus

Cloud that is high level and wispy or light and patchy in form, made of ice crystals and is always up high.

Cumulus

Form of cloud that is puff balls, often with a flat base (but can lose flat base due to air circulation).

Stratus

Form of cloud in sheets or layers, that may cover the whole sky, and doesn't have separate clouds.

Cirrocumulus

Form of cloud that is high in level and puff ball in form.

Cirrocumulus

High level puffy ball clouds.

Cirrostratus

high level, very light layers of cloud.

Alto

general term for clouds that are at mid level

Altocumulus

mid-level puffball clouds.

Altocumulus

clouds that are mid-level, and bigger and denser than cirrocumulus.

Altostratus

clouds at mid-level that form a light sheet that lets the sun or moon show as a bright spot.

stratus

general term for clouds that are low level

stratus

low level layers of cloud that often cover much of the sky

stratocumulus

clouds that are low-level layers of cumulus clouds, that begin to touch each other and fuse.

Nimbostratus

clouds that are low-level, uniform layer, usually very dark, that bring strong precipitation.

Nimbus

general term for clouds that means rainy in Latin.

Cumulonimbus

Clouds that are the product of growth of cumulus which can form huge thunderheads.

Fog

a cloud that forms at or near the ground.

Mist

precipitation that reaches the surface in liquid drops of the smallest size. 0.005-0.05mm diameter.

Drizzle

precipitation that reaches the surface in liquid form, drops 0.05-0.5mm diameter.

Rain

precipitation that reaches the surface in liquid form, drops 0.5-5mm diameter.

Snow

precipitation that reaches the surface in form of ice crystals or aggregates of crystals

Sleet

precipitation that reaches the surface in form of small ice particles. Often falls as rain but then passes through a cold layer that freezes the drops.

Hail

precipitation that reaches the surface in form of larger pieces of ice. Formed in cumulonimbus clouds in updrafts of up to 100mph.

Glaze

forms when rain freezes as it hits a freezing surface, forming a thin coating of ice. Eg black ice.

Rime

deposit of ice crystals that forms directly on cold surfaces from fog.

Graupel

Soft hail, which forms when rime coats snowflakes on their way down.

Bergeron Process

formation of precipitation, where water condenses, and freezes, then falls frozen or melted as rain.

Collision-coalescence process

formation of precipitation, where tiny droplets accumulate, fall, and collide with other small droplets until rain drops form and fall.

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions above and try again

Example:

Reload the page to try again!

Reload

Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

NEW! Voice Recording

Create Set