Saharan Air Layer LabName: ______

HR: _____ Date: ______

Materials:

Data Sheet

Large clear containerscissors

Medium containerpencil with sharp point

Small plastic cupice water

Weights (nuts/bolts)warm water

Food coloring (red and blue)room temperature water

Kitchen plastic wrapsafety goggles

Rubber bandthermometer

Lab Prep

1. Put on your safety goggles. Place a large metal nut in the small cup to act as a weight. Add a few drops of blue food coloring and then fill the cup to its brim with room temperature water. Take the temperature of the water in the cup and record the data.

2. Make sure the blue coloring in the cup is mixed thoroughly, and then cover the cup with a piece of kitchen plastic wrap. Pull it tight over the top of the cup, and secure it with a rubber band to ensure a tight seal.

3. Position the sealed up in the center of the large plastic container. Slowly fill the large clear plastic container with ice water at least 3 cm above the top of the small cup. Remove any pieces of ice that might have transferred to the container. Take the temperature of the ice water and record the data.

4. With a very sharp pencil, poke several small holes in the plastic wrap covering the small cup. Observe and describe what happens as the colored water mixes with the cold water in the larger container.

Next, you will build a new model to observe a temperature inversion layer similar to that present in a Saharan Air Layer event.

5. Clean out the large container and the small cup. Repeat steps #1 through #3 to set up the experiment again. Be sure to take the temperature of the water in the small cup and the ice water, and record those values again.

6. Place a sheet of plastic wrap on the surface of the ice chilled water so that it goes edge to edge inside the container, like a blanket that covers the water below.

7. In the medium-sized container, add warm water, enough to fill another 3-5cm in the large container, and add red food coloring. Take the temperature of the warm water and record the data. Carefully pour the warm, red-colored water onto the surface of the plastic wrap inside the large container.

8. Gently remove the plastic wrap barrier.

9. Once again, use a sharp pencil to gently poke holes in the plastic wrap that is sealing the small cup in the bottom of the large container. Do not cause any stirring motion as you do this.

------TURN OVER------

Make Observations

1. Describe what happens when you poke holes into the plastic wrap on the small cup.

2. For several minutes, carefully observe the movement of the dyed water that emerges from the cup. What path does it follow? Describe the movement that you observe. Why do you think this is happening?

Interpret the Data

Explain the relationship between the temperatures of the three water samples and the mixing behavior that you observed.

Saharan Air Layer Data SheetName: ______

HR: ______Date: ______

Lab Prep:

Temperature of room temperature water: ______

Temperature of ice water: ______

Observations of the waters mixing:

Lab:

Temperature of room temperature water: ______

Temperature of ice water: ______

Temperature of warm water: ______

Observations of the waters mixing: