GEOG155 | Chapter 6

Glaze

(aka freezing rain) Water falls as liquid, freezes to surfaces

Hail

-Produced in cumulonimbus clouds -Strong updrafts required -Composed of roughly concentric layers of clear and cloudy ice

Frost

-Simply a cloud on the ground -Frozen dew -Occurs when air temperature lowers to saturation point, when the saturation point is below 0degrees C (32degrees F) -Will appear as large numbers of small white crystals.

Dew

-moisture condensation on surfaces that have been cooled to saturation -Usually originates from terrestrial radiation -Will appear as water droplets

Lifting condensation level (LCL)

Altitude in which rising air cools sufficiently to reach 100% relative humidity at the dew point temperature and, thus, condensation beings **clouds with flat bottoms

Saturated mixing ratio

Maximum amount of water vapor that could be held in a parcel of air at a given temperature

Sleet

Small raindrops that freeze during descent and reach the ground as small pellets of ice

Lifting mechanisms: Convective

Surface air that is heated and, thus, is rising

Humidity

The amount of water vapor present in the air

Cloud

The visible accumulation of tiny liquid droplets of ice crystals suspended in the atmosphere

Mixing Ratio? and is expressed by...?

actual amount of water vapor present in air; expressed as grams of water vapor per kilograms of air

depression of the wet bulb

after whirling, the difference between the wet bulb temperature and dry bulb continues.

Lifting mechanisms: Orogaphic

air forced over a topographic barrier

Lifting mechanisms: Frontal

air forced upward due to collisions of two different air masses

Lifting mechanisms: Convergent

air forced upward due to convergence of air, winds

stratus

blanket like

snow

cloud ice crystals formed when water vapor is sublimated directly to ice

All precipitation originates in _____, but most _____ do not yield precipitation

clouds

Hydrologic cycle: water is in...

constant cycling and various states (i.e. solid to gas)

Condensation

conversion of vapor to liquid water

Low precipitation regions...

deserts and poles

Hydrologic cycle

formation of fog, haze, clouds, and precipitation

Cirrus

high, thin wispy, ice crystals

Long term impacts of precipitation on Earth's surface?

i.e. caves

Short term impacts of precipitation on Earth's surface?

i.e. floods

As air temperature increases, the capacity of the air to hold water vapor _____ and vice versa

increases (i.e. dry winter air vs. humid summer air)

sling psychrometer

instrument that is used to measure both relatice humidity and the dew point

100% Relative humidity means that the air

is saturated and has reached its carrying capacity

What's the most common and widespread form of precipitation?

rain

dew point

temperature at which a parcel of air reaches 100% relative humidity

Relative humidity (RH)

the amount of water vapor given parcel of air compared to the total amount of water vapor that could be held in that same parcel at a given temperature

High precipitation regions...

tropics