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
