06 Water vapor and storms

Experiment: The effect of increased water vapor on storms

See how the amount of water vapor in air affects the formation of clouds and storms. "Cloud in a jar experiment"

Time: 30 minutes

Level: Beginner

Materials

3 empty metal cans ~ 15 oz, or cardboard tubes ~ 3” diameter and ~4” tall
Electrical tape to add friction to edge of tube, and cover sharp edges as needed
3 tea lights, (steady light, not flickering)
3 jars with large openings, size ~ 16 - 24 fluid oz, either plastic or glass
3 metal lids (usually come on the glass jars) or 3 pieces of thin plastic mesh (from a bag of oranges, a shower scrubber, etc.)
Aerosol spray (such as Static Guard, or unscented hairspray)
Digital thermometers (optional)
Hot and cold water
Ice cubes
A dark space to watch the experiment, or a cardboard box to block ambient light

Specifics and purchasing links are on this spreadsheet Materials list for CCSAE experiments

Procedure

Step 1

Prepare 3 lighted stands for the jars using metal cans or cardboard tubes

Remove bottoms from the cans if possible

Cover top edge of the cans/tubes with electrical tape to prevent jars from tipping over

Collect 3 tea lights with steady light and similar brightness.

Step 2

Create a dark theater to observe the experiment. An empty cabinet or a cardboard box on its side could work well.

The space must be tall enough to fit the jars and the cans or tubes they are standing on.

The jars should be at eye level, so look for a space where observers can be directly in front of the jars.

Block or reduce ambient light by closing doors and window shades.

Step 3

Prepare ice holders from the lids of hte jars

The ice will be at the top of the jar in an ice holder. The ice holder must “conduct cold” from the ice to the air in the jar. (Properly stated, the ice holder must conduct heat from the air in the jar to the ice.)

Metal lids from the glass jars are very good thermal conductors (conductors of heat). If you have metal lids, turn them upside down and place a few ice cubes in each.

Plastic lids from the plastic jars are not good thermal conductors, but can be used to support the ice in a mesh sack.

If you have plastic lids, turn them upside down and place a few ice cubes in each, then secure the ice cubes with pieces of thin mesh. NEED PIC

Step 4

Set up the dark theater, and collect the cans and tea lights

Place the tea lights in the cans

Have the iced lids ready near the cans

Step 5 Prepare the cloud jars

Prepare 3 jars with water in 3 different temperatures.

The water does not need to be boiling or freezing. Hot and cold tap water can be the extremes. Combine the hot and cold water together in equal amounts to find a medium temperature.

Suggested temperatures:

Hot: 120 °F (50 °C)

Medium: 90 °F (33 °C)

Cold 60: °F (15 °C)

Label the jars and fill each with about 1 ½ “ of water

Step 6 Create clouds

Put the jars on top of the cans and the iced lids on top of the jars

Spray aerosol in each jar and cover it with an iced lid

Watch clouds form and compare the 3 jars

Open the lids and watch the clouds emerge. Touch the clouds and notice the temperature

Video Clouds experiment - Water vapor fuels storms shows the experiment with glass jars, then with plastic jars. Both use metal lids.

Note: to reduce condensation on the walls of a glass jar, warm up the glass jars before adding the 3 temperatures of water. FIll each with hot water and let them sit for a few minutes until the jars feel warm on the outside. Pour out the water and use the warm jars in the experiment.

Observations:

More clouds formed over the warmer water

The clouds felt cool, so they were not steam

Conclusion:

The jar with the warmest water yielded the most clouds.

Clouds are formed when water vapor condenses into water droplets or ice crystals.

The warm water in the jar heated the air and evaporated into the air, creating warm air with a lot of water vapor. As the warm air rose up and came in contact with the ice or cold surface the water vapor condensed into cloud particles and began to sink.

Draw your own conclusion (open this box to see our suggestions)

Suggestions:

Rain comes from water vapor in the air

Hurricanes come from water vapor in the air.

Warm air and warm water make hurricanes worse.

Identify the physical, chemical or biological mechanism that is happening (open this box after you have an idea)

The mechanism is evaporation from warm water

Relate this mechanism to climate change

Find the arrow (→) in the framework that represents this mechanism (starts at the cause phenomenon and goes to the effect phenomenon). (Use your printed copy of the framework, or open the one here.)

Pathway for Extreme and Changing Weather.pdf

Open this box to check your connection.

Then go to the Explainer pages to learn more about the Cause and Effect phenomena

Connection 6

Cause: More water vapor in air

What is happening: extra water vapor fuels hurricanes and affects weather patterns

Effect: Extreme weather and changing weather patterns

We’d love to hear how you used this tool in your community, how the students responded, and your suggestions to improve the experiments and other resources. Contact us at ccsae@mit.edu.