This document discusses various cloud formation processes and types of precipitation. It explains that clouds form through processes like adiabatic lifting and convergence which cause air to rise and condense. Specific cloud formation mechanisms covered include orographic lifting, frontal wedging, localized convection, and stability/instability. The document also defines different cloud types from high, middle and low clouds to clouds with vertical development. Additionally, it covers fog formation and the processes that cause precipitation like rain, snow, sleet, glaze and hail.
2. Adiabatic Temperature changes and
Expansion cooling
• Heat not added or subtracted when
temperature changes
• Traveling up earths surface atmospheric
pressure decreases because of fewer gas
molecules
• Dry adiabatic rate- rate of cooling and heating
applied to unsaturated air.
• Wet adiabatic rate- slower when cooling cause
by latent heat.
3. Orographic Lifting
• Elevated terrains acting as barriers to air flow
making orographic lifting occur.
• Orographic air- lifts air
• Most moisture is lost by the time air reaches
leeward side of a mountain
4. Frontal wedging
• Warm air and cool air collide producing a front
• In North America cooler denser makes
warmer less dense air rise.
• Warm is rising the cool air is toward the
bottom forming rain
5. Convergence
• Air in the lower atmosphere flowing together
makes the air go up which is called
convergence
• Pattern of air movement and uplifting is
accompanied by solar heat
• Florida experiences great amount of mid
afternoon thunderstorms
6. Localized Convective Lifting
• Pockets of air may occur due to unequal
heating on summer days
• Rising parcel of warm air called thermals
• Clouds form when warm parcel air rises above
condensation
7. Stability
• Volume air rise- temperature decreases do to
expansion
• Volume air cooler- environment ,more denser
• Stable air- resists vertical air
8. Condensation
• Occurs when water vapor liquid
• Water vapor liquid can be in the form of
dew, fog, or clouds
• Air must be saturated before any of the forms
of condensation occur
9. Types of cloud
• Cirrus and cumulus
• Cirrus- white, thin, high clouds
• Cumulus- rounded individual cloud masses.
• Stratus- a cloud with layers that cover much of
the sky
10. High Clouds
• Cirrus, Cirrostratus, and cirrocumulus make up
a high cloud
• White, thin and often made up of ice crystals
• May leave a warn of stormy weather
approaching
11. Middle Clouds
• In the middle and alto is part of their name
• Is an altocumulus cloud which is denser and
larger
• Light snow or drizzle is infrequent
12. Low Clouds
• Stratus, Stratocumulus, and nimbostratus are
all apart of the low cloud
• May produce light precipitation
• More towards the bottom and weather occurs
more
13. Clouds of Vertical Development
• Clouds are more lower but stretch to higher or
middle altitude
• Associate with unstable air
• Cumulonimbus cloud may produce rain
showers or thunderstorms
14. Fog
• Fog formation- when earth surface cool
rapidly on cool, calm, clear nights
• Air more denser, making thick fog occur
• Cool air evaporates over warm water
producing saturation
• Same structure and shape as a cloud
15. Cold Cloud Precipitation
• Cold air does not freeze at 0*C.
• Water in liquid state at 0 degrees Celsius is
called super cooled
• Ice crystals cant coexist with water droplets in
air due to super saturation on ice crystals
16. Warm Cloud Precipitation
• Warm clouds- mechanism forming water
droplets in collision-coalescence process
• Salt able to remove water vapor from the air
at relative humidities
• Large droplets moving through cloud collide
and coalesce with smaller slower droplets
17. Rain and Snow
• Rain- drops of water fall from a cloud
• Low temperature six sided ice crystals form
which makes snow
• At -5 degrees Celsius ice crystals join together
as clumps
18. Sleet, Glaze, and Hail
• Sleet- fall of small particles of clear ice
• Glaze-known as freezing rain, occurs when
raindrops get super cooled
• Hail-begin as small ice pellets, growing by
collective super cooled water droplets.