Clouds and Precipitation

By: Meredith Pesce

Adiabatic Temperature Changes And Expansion and Cooling

Adiabatic Temperature Changes

• Change in Temperature, with out anything being added to the air.

• Dew point stays the same• Requires energy to move

molecules around.Expansion and Cooling• For every 1000 meters you

go up, them temperature will cool 10 degrees Celsius

• Works vice versa

http://www.kidsgeo.com/geography-for-kids/0070-adiabatic-temperature-changes.php

Orographic Lifting

• Objects like mountains or hills block air flow• As the air rises, it cools. Often creating

condensation.• Later it heats up on the other side of the

mountainhttps://earthscience-in-the-nationalparks.wikispaces.com/Death+Valley

Frontal wedging

• When warm and cool air collide creating a weather “front” which pushes air across a certain area

• Cool denser air acts as a barrier • Then causing the warmer, less dense air, to ride

http://www.geo.hunter.cuny.edu/~tbw/wc.notes/4.moisture.atm.stability/frontal_wedging.htm

Convergence

• When Air in the lower atmosphere flows together to give lifting results.

• When the two masses hit they flow upwards• This generally creates Adiabatic Changes

http://apollo.lsc.vsc.edu/classes/met130/notes/chapter6/lift_converge.html

Localized Convective Lifting

• Un-even heating of Earths surface from air particles

• When the warm air rises above a certain condensation point it can create clouds

• It also creates thermals which is rising hot air and birds can use it to fly.

http://rst.gsfc.nasa.gov/Sect14/Sect14_1cl

Condensation

• Condensation is a change from gas to liquad• It can only occur on surfaces, usually like a car

window, grass and a glass.• The particles are so fin the san just suspend in

air until there is something to condensate on.

http://keep3.sjfc.edu/students/kes00898/e-port/condensation%20page%20for%20unit.html

Types of clouds

• Cirrus: Often look like the pieces of a ripped up cotton ball, little wispy hairs.

• Cumulous: Rounded clouds which look• like domes, or powdered sugar. • Stratus: Like a sheet in the sky. It covers the

sky in layers

High Clouds

• Generally these clouds are made of tiny little ice crystal

• These clouds usually do not precipitate • The seem to be very light

http://www.ksl.com/?nid=341&sid=148078

Middle clouds

• You can see the sun and moon’s light through these clouds• They are white and gray• Slightly fluffy but arent too dense

http://www.flickr.com/groups/skyandclouds/discuss/72157606548215685/

Low clouds

• Accumulate around mountain ranges• Mostly stratus clouds• Mad up of little water dropletss

http://www.free-online-private-pilot-ground-school.com/Aviation-Weather-Principles.html

Clouds of Vertical Development

• These are generally cumulonimbus clouds• The could happen around places that have

unsteady air • Often create precipitation

http://www.astrobio.net/pressrelease/3936/the-secrets-of-the-rain

Fog

Caused by Cooling• When cold prevailing winds

meets damp warm air it creates fog

• Also when a freezing popsicle lands on a warm black top its instantly creates fog

Caused by warming

• When moisture evaporates and creates saturation

• Generally happens when cold air moves over warm water

http://houseforlorn.blogspot.com/2008/09/river-of-clouds.html

Cold Cloud Precipitation

• There is a lot of water in these clouds so the don’t start freezing until they are in a range of -32f to -40f degrees.

• Clouds create snow and or hail• The water vapor will condense faster on

colder ice like objects

http://rst.gsfc.nasa.gov/Sect14/Sect14_1d.html

Warm Cloud Precipitation

• This happens when air is fully saturated• The growth of a water droplet occurs when it merges with other droplets as its falling out of the cloud• As it cools condensation will occur onWater soluble materials

http://san.hufs.ac.kr/~gwlee/session8/droplet.html

Rain And Snow

• Rain is just large water droplets that are large enough to reach the ground

• It could take many droplets of water to create one that will touch the ground

• If we pollute to much we can create acid rain

• Made up of frozen water crystals

• In order for snow to fall it must be below 32f degrees.

http://www.nelsoncountylife.com/2010/11/03/snow-showers-possible-in-highest-elevations-late-thursday-night/

Sleet, Glaze and Hail

• Sleet is created by layers of a raindrop which all have different temperatures as they fall from the sky

• Glaze occurs when a light rain covers trees or grass which an catch the rain

• Hail is just uneven frozen water droplets in clouds

• They usually form in thunder storms and heavy clouds

http://cs.wikipedia.org/wiki/Ledovka