Station 1: Humidity and Dew Point Question: What are some ways in which we measure water vapor in the atmosphere? How can we determine the dew point of the classroom? Materials: Ice, metal can, thermometer, tub of water, sponges of different size Instructions: 1. Place each of the sponges in the tub of water so that they are soaked. This represents an atmosphere with 100% humidity. The sponge (atmosphere) is said to be saturated at this point. 2. Squeeze each sponge into a beaker so that half of it is relatively dry and half is still wet. Examine the amount of water in each beaker. Consider the temperature of air represented by each sponge. 3. Fill the metal can with room temperature water (dry the can before starting if necessary). Note the temperature of water. 4. Slowly add ice cubes to the can (slowly stir) until water droplets form on the outside of the can (dew). 5. Record the temperature of the water when “dew forms”. This is the dew point temperature of the classroom. 6. Empty the can before moving to the next station. Words Worth Knowing: ● Dew Point: the temperature at which water vapor will condense to form a liquid ● Absolute Humidity: the total mass of water vapor in the air ● Relative Humidity: the amount of water vapor in the atmosphere compared to the amount the atmosphere can contain at a given temperature Guiding Questions: ● What was the relative humidity of each sponge when half of the water was squeezed out? ● Why didn’t each sponge “hold” the same amount of water? ● Which sponge had a greater absolute humidity? ● Where did the water that formed dew on the outside of the can come from? In Your Notebook: a. Sketch a diagram that illustrates the concepts of absolute vs. relative humidity. b. Sketch well annotated models that show what happens to water vapor around the warm can and around the cold can. .
Transcript
Station 1: Humidity and Dew PointQuestion: What are some ways in which we measure water vapor in the atmosphere? How can we determine the dew point of the classroom?
Materials: Ice, metal can, thermometer, tub of water, sponges of different size
Instructions: 1. Place each of the sponges in the tub of water so that they are soaked. This represents an atmosphere with 100% humidity.
The sponge (atmosphere) is said to be saturated at this point. 2. Squeeze each sponge into a beaker so that half of it is relatively dry and half is still wet. Examine the amount of water in
each beaker. Consider the temperature of air represented by each sponge. 3. Fill the metal can with room temperature water (dry the can before starting if necessary). Note the temperature of water.4. Slowly add ice cubes to the can (slowly stir) until water droplets form on the outside of the can (dew).5. Record the temperature of the water when “dew forms”. This is the dew point temperature of the classroom.6. Empty the can before moving to the next station.
Words Worth Knowing:● Dew Point: the temperature at which water vapor will condense to form a liquid● Absolute Humidity: the total mass of water vapor in the air ● Relative Humidity: the amount of water vapor in the atmosphere compared to the amount the atmosphere can contain at a
given temperature
Guiding Questions:● What was the relative humidity of each sponge when half of the water was squeezed out?● Why didn’t each sponge “hold” the same amount of water? ● Which sponge had a greater absolute humidity?● Where did the water that formed dew on the outside of the can come from?
In Your Notebook:a. Sketch a diagram that illustrates the concepts of absolute vs. relative humidity.b. Sketch well annotated models that show what happens to water vapor around the warm can and around the cold can.
.
Station 2: Cloud Formation (Activity)Question: How do temperature and atmospheric pressure relate to cloud formation?
Materials: matches, warm water, plastic container with thermometer, plastic tub for waste water
WWK:condensation nuclei: tiny particles (such as smoke or dust) in the air that allow water vapor to condense and clouds to form.
Instructions:1. Note the temperature on the thermometer in the bottle at the table. The brightest color represents the temperature.2. Gently squeeze the bottle (be sure that the lid is on tight) and hold for a minute. Watch the thermometer. Consider
what is happening to the air molecules inside the bottle. 3. Pour a small amount (just to cover the bottom) of warm water into the plastic container. Close the cap and shake. 4. Open the bottle and add smoke from the match provided. (get a teacher to help at this point) 5. Close the cap and squeeze again. Hold for about 10 seconds, then let go. Observe what happens. Repeat the process of squeezing and letting go several times. 6. Clean up your area when done. Empty all water out of the bottle into the plastic tub provided.
Discussion Questions:● Discuss why the temperature changes that you observed occurred. What might cause these changes in the atmosphere?
How do the changes relate to pressure?● Describe what you observed when water and smoke were added.
In your notebook:Draw a well annotated model that shows what happens when the bottle is squeeze and expanded. Be sure to include the following:
● water (vapor or liquid) ● pressure● temperature.
Also, describe how the motion of molecules changes.
Station 3: Cloud Formation (foldable notes)
Question: What are some common situations in which clouds can form?
Words Worth Knowing: ● orographic; clouds or rainfall resulting from uplift of air due to the presence of mountains.
Instructions: 1. Fold and label one of the half sheets of paper provided like the model shown.2. Read the handout provided. Fill in the notes using the information from the reading.
Guiding Questions:● What conditions lead to cloud formation?● Why might the west side of the Cascade Mountains (Seattle, Portland) receive lots of rainfall while the east side is relatively
dry?● Examine the precipitation map of the island of Hawaii. What inferences can you make about the prevailing winds? Keep in
mind that Mauna Kea and Mauna Loa mark the highest peaks.
In Your Notebook:Glue in the half sheet of notes that you created. Woohoo! Way to go:)
Extensions: https://climate.ncsu.edu/edu/k12/.cloudformation (graphic and reading)https://www.youtube.com/watch?v=-YySltYzvtU (Video)
Question: What is the relationship between air pressure and winds?Materials: Air pressure analysis page, stress squeeze toy, balloons
WWK: isobar: a line connecting areas of equal atmospheric pressure
Instructions:● As a group, use two balloons. Alternately blow up (not completely) the balloons and let them go. What
causes the wind that is observed?● Examine the handout provided titled “air pressure analysis” . Follow the instructions on the handout. ● Compare your map to the hurricane map provided. Discuss any differences you notice.
Guiding Questions:● How are atmospheric pressure and wind related?● What might cause the strongest winds?● What might cause the winds to blow clockwise around highs and counterclockwise around lows?
In Your Notebook:Glue your isobar map into your notebook.
Extensions: Ask the meteorologist: https://youtu.be/UVaBgndWNGsFastest ever winds: http://usatoday30.usatoday.com/weather/tornado/wtwur318.htmHaboob (crazy wind with dust): https://youtu.be/kJBsaTVsb3Q
Hurricane Sandy hit the Caribbean and East Coast of the United States in October 2012 with winds of 80 mph. The storm killed 149 people.
Station 5: Coriolis EffectQuestion: What causes winds to move clockwise around low pressure areas and counterclockwise around high pressure areas?
Materials: lazy susan, white board marker, brain….
Words Worth Knowing:Coriolis effect: the imaginary force that deflects objects, such as rockets or large storms, which move over the surface of some planets. It is important in causing the swirling motion of storms, including hurricanes. The Coriolis effect occurs on Earth and other planets because the planets rotate.
Instructions: Cover the turntable with the paper, taping it to the edges of the turntable. Use one of the markers to draw a straight line all the way across the turntable. This shows the path of clouds or objects moving on a non-rotating planet.
Discuss: Observe and describe the shape of the line you drew. Looking down on your line is it straight or curved?
Discuss: What is wrong with (missing from) this model of the Earth that might affect how objects truly move over the Earth’s surface?
Now spin the turntable counterclockwise. This is the direction that the Earth turns (or rotates), when viewed from the north pole. The turntable is modeling the northern hemisphere of the Earth. Draw a straight line across the turntable using a different colored marker, while spinning it at a constant speed. Be sure to watch that your marker follows a straight path! Label the beginning of the line you drew with an arrow pointing in the direction the marker moved. Note that the line you drew is a curve.
Discuss: With the starting point of the line directly in front of you, in which direction was line deflected? (Which way does the arrow point—right or left?)
Discuss: Which direction does the line curve (clockwise or counterclockwise)?
Discuss: If you were in an airplane that takes off from Miami, Florida and is flying to Toronto, Canada, would your plane be deflected to the left or to the right as it flew?
Station 5: Coriolis EffectInstructions (continued): Now spin the turntable clockwise. This is the direction that the Earth turns (or rotates), when viewed from the south pole. The turntable is modeling the southern hemisphere of the Earth. Draw a straight line across the turntable using a different colored marker, while spinning it at a constant speed. Be sure to watch that your marker follows a straight path! Label the beginning of the line you drew with an arrow pointing in the direction the marker moved. Note that the line you drew is again a curve.
Discuss: With the starting point of the line directly in front of you, in which direction was line deflected? (Which way does the arrow point—right or left?)
Discuss: Which direction does the line curve (clockwise or counterclockwise)?
Discuss: If you were in a cruise ship that set sail from Cape Town, South Africa and was sailing for Rio de Janeiro, Brazil, would your ship be deflected to the left or to the right as it traveled?
Discuss: What is the difference between the way objects move over the Earth in the northern hemisphere com-pared with those in the southern hemisphere?
Examine Figure 7.1, which shows part of Mars. The bright streaks associated with some craters can be used as wind direction indicators. They are deposits of dust that can form downwind from craters.
Discuss: Does the group of streaks form a straight or a curved path (as a whole group)?
Discuss: What does the shape of the wind streaks indicate about the existence of a Coriolis effect on Mars?
Discuss: Does Mars rotate? What evidence do you have of this?
Discuss: From which way did the wind blow to make the streaks in Figure 7.1?
Discuss: Imagine you are on the part of Mars shown in this figure, standing with the wind to your back. Which way is the wind being deflected, to your left or your right?
Discuss: If Mars rotates in the same direction as the Earth (from west to east), is this a picture of the northern or southern hemisphere of Mars?
Station 5: Coriolis EffectIn your notebook:
Summarize what you have learned about the Coriolis effect. Include the following:
1. What causes the Coriolis effect?2. What are the impacts on weather from
the Coriolis effect?
Write down three questions that you still have about the Coriolis effect.
Interesting Misconception:
Though many people have seen videos of toilets flushing in Australia and the U.S. that swirl in opposite directions, these experiments are based on luck and, perhaps not surprisingly, the toilets' varying designs. Pranksters have even gone so far as to blame the Coriolis effect for hair curling in a certain direction.
Question: What happens when two air masses collide?
Word Worth Knowing: Density: mass divided by volume. Measure commonly in g/mlAir Mass: a large volume of air with a similar temperature and moisture contentFront: The boundary between two air masses.
Instructions:1. One person may want to video the activity to help with the sketches later.2. Fill the clear container with water to a depth of 3 to 5 millimeters (no deeper!).3. Slowly pour the corn syrup (1/2 cup) into the water.4. Quickly observe and sketch the appearance and location of the boundary between the water and
the corn syrup.5. (In your notebook) Make three sketches: once early during the pour, once after the corn syrup is halfway poured out
of the container, and finally about a minute after the pour is complete. 6. Clean out the container when you are finished.
Discussion Questions:● Discuss how the density of the corn syrup differs from that of the water. How do you know?● Which substance represents cold air, which represented warmer air? Why?● Describe what happened where the two materials met? ● Do you think that this model best represents a cold front or a warm front? Why?
In your notebook:● Under your sketches (from #5 above) explain what you would expect the weather to be like where the two materials
collide.
Station 7: Fronts Reading and Notes
Question: How do different types of fronts impact weather?
Words Worth Knowing: front: the boundary between two air massesair mass: a large volume of air with similar temperature and moisture content
Instructions:1. Fold the paper provided like the model shown.2. Glue each image on the correct square3. Read the page provided. 4. Inside each flap record what occurs and how the front impacts the weather. In addition, record the symbol for each type of
front.5. Examine the weather maps provided. Discuss what you would expect around the country in terms of weather based on the
locations of fronts on each map.
In your notebook:Glue your foldable notes into your notebook.
