2. Adiabatic Temperatures
Changes
•When air expands it cools, then when
it compressed it is warm
•Expansion (dry adiabatic rate) is a
rate of cooling or heating only to
unsaturated air. As you go up through
the atmosphere the pressure decrease,
this happens because there is less gas
molecules
•Cooling (wet adiabatic rate), is above
the condensation level, it rise 5 Celsius
for every 1000 meters
3. Orographic Lifting
•As air goes up mountain slopes the adiabatic
cooling creates clouds and precipitation
•This process only occurs because of the
mountains or elevated terrain acts as walls of
barrier
4. Frontal Wedging
•When a cold front meets a warm front and
the cooler front which is more denser acts as
a wall over when the warmer less dense air
rises
6. Stability
• Stability is measured by using temps. of atmospheres
at various heights
• Temperature decreases as altitude increases
• When clouds make contact with up lifted air it
usually creates thunderstorms, and maybe a tornado
7. Localized Convective
Lifting•On warm summer days, unequal
heating of Earth’s surface may cause
pockets of air to be warmed more than
surrounding air
•Spots and parcels are called thermals
•Stability is measured by using temps.
of atmospheres at various heights
•Temperature decreases as altitude
increases
•When clouds make contact with up
lifted air it usually creates
thunderstorms, and maybe a tornado
8. Condensation
For any condensation to be formed air must be saturated
Types of clouds:
Stratus- covers most of the sky.
Cumulus- have flat bases, described as cauliflower
structure, they are round individual cloud masses.
Cirrus- white and thin, they come in groups of patches.
9. High clouds
Family of high clouds; cirrus, cirrostratus,
and cirrocumulus
High clouds are thin and white
10. Middle Clouds
Prefix of alto- as part of their names
Large and dense
Clouds that appear in middle range are
about 2000 to 6000 meters above ground
11. Low Clouds
Three members- stratus, stratocumulus,
and nimbostratus
Produce light precipitation
Stratus clouds like a fog layer that covers
most of the sky
Nimbostratus are the rain makers
12. Clouds and Vertical Development
All clouds are related and associate with unstable air
Once there is up ward movement, clouds form with
vertical range, when this happens cumulonimbus
makes rain and thunderstorm
13. Fog
Fog is defined as a cloud with its base at or very near the
ground
Fog is caused by radiation cooling or the movement of air
over a cold surface can also form when enough water vapor is
added to the air to bring about saturation
Caused by cooling- as air becomes cooler then gets denser and
drains into to fiver valleys
Caused by evaporation- when it covers over lakes in fall and
early winters
14. Cold Cloud Precipitation
Bergeron process – two physical processes: super
cooling and super saturation
Super cooled- liquid state below 0 Celsius.
Super saturated- it has greater than 100 % humidity
15. Warm Cloud Precipitation
Collision-coalescence process- it is a
mechanism that forms raindrops
Large droplets go through sky they collide
with other small and slower droplets
16. Rain and Snow
In meteorology rain means drops of water that falls
from a cloud and has a diameter of at least .5 mm.
Smaller drops are called drizzle
When temperature is low light fluffy snow comes
down, if temperature is warmer then -5 degrees
Celsius they join together
17. Sleet, Glaze, and Hail
Sleet- of small particles of clear to-transparent ice. For it
to form a layer of air with temperatures above freezing
must overlie a subfreezing layer near the ground.
Glaze- is also known as freezing rain, this happens when
the rain drops get supercooled and fall through
subfreezing air they turn into ice.
Hail- produced in cumulonimbus clouds. First start out as
ice pellets then they get bigger as they collect
supercooled water droplets as they go through the cloud.
Ice pellets can go back up and then back down if they
emerge with an updraft.
