04 Evaporation over warmer oceans

Experiment: Water vapor levels in air of various temperatures

Compare the amount of water vapor in saturated air of various temperatures.

Time: 30 minutes

Level: Intermediate

Materials

4 similar glass jars, 16 to 24 oz (500 to 750 ml) such as mason jars or pickle jars
Thermometer, analog or digital. Ideally 1 for each jar.
Electric kettle or other device to heat water
Ice cubes
Plastic sheet to cover jars. Do not use “Saran” wrap as it will stretch under the ice. Sandwich bags cut apart will work well.
Rubber bands

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

Procedure

Step 1

Start the investigation by filling 4 jars with water at these temperatures:

Ice water
Room temperature
Hot tap water
Boiling water

Wait a few minutes until each jars is at the same temperature as the water in it. Do this by holding temperature probes in the middle of the water until the reading stabilizes, then adding cold or hot water to achieve the desired temperatures.

Step 2

Pour out most of the water, leave ~ ¼ in, cover with a plastic sheet and seal with a rubber band

Step 3

Place a few ice cubes on top of each jar

Step 4

After 5 minutes, remove the ice, dry the tops and observe the water condensed on the plastic

Tap the tops as needed to get the droplets to collect.

Step 5

If there is not much condensation, repeat steps 3 and 4

Step 6

Remove the ice, dry the tops and observe the water condensed on the plastic sheet

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

Suggestions:

The jars with warmer water had more condensation.

More water evaporated from the warmer water.

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

The mechanism is evaporation

Warmer ocean waters cause more evaporation (more water goes into the air as vapor)

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 Environmental Explainer pages to learn more about the Cause and Effect phenomena

Connection 4

Cause: Warmer ocean water

What is happening: there is more evaporation from warmer water

Effect: More water vapor in the air

The air over a warmer ocean will have more water vapor available to it than over a colder ocean

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.