Transcript Day 32

Day 32
Investigation 6 part 4
Clouds & Precipitation Cont.
Day
32
Imagine you are climbing a mountain. What
will happen to the air pressure around you as
you climb?
It will decrease because there is less
and less air above you.
What will happen to the temperature?
It will also decrease, because
temperature decreases when pressure
decreases.
2
Daily Warm-Up Exercises
Cloud Formation
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Have you seen any clouds lately?
What did they look like?
Where are clouds?
Are they always in the same place?
What is a cloud?
What is it made of?
Where do clouds come from?
How do you think they form?
Cloud in a Bottle?
• Using a 2-liter soda bottle, containing 25 mL
of water
• Water vapor into the air?
–Shaking the bottle
–Warming the water
Shake, shake, shake
• Have we formed a cloud yet?
• NOT YET
Water Vapor?
• Increase energy inside the bottle to make the
water turn to vapor?
• Remember:
–Temperature and pressure
–Increased temperature = increasing pressure
Cloud recipe
• Saturate the air with water vapor
–Shake the bottle
–Warm the bottle by holding it in your hands
–Increase the pressure to increase the temperature
• Then
–Release the pressure on the bottom to decrease the
temperature (to get the water vapor to condense dew point)
Did it Work?
• NOT YET!
• There is a piece missing
• There is nothing for the water droplets to form
on!!
Condensation Nucleus
• Clouds are composed of tiny droplets of
condense liquid water
• Water vapor is condensing on the particles of
smoke and the plastic of the bottle
• The particle on which water vapor condenses
in the air to form a cloud
In Real Clouds
• What would be the condensation nuclei in the
outside air?
–Dust
–Smog
–Air pollution
–Smoke
–Salt
–Chemicals
Precipitation
• Water that falls from the sky
• Kinds of precipitation
–Rain
–Snow
–Sleet
–Hail
Raindrops and Cloud Droplets
• Measure the average diameters
• Comparison of size - page 80 in the Resource
Book
Measuring Precipitation
• Most important weather factors monitored
• Measured with a rain gauge
Labels
Visualization Exercise 6.2
Resources, P. 38
Reading
• Open to page 37 of the green resource book.
• Read “Observing Clouds”
• Answer the questions at the end of the reading.