The following demonstration shows the meeting of a warm and cold air mass and will show the lack of mixing that occurs when air masses meet in a location on earth. The meeting of air masses will often cause severe storms as the two air parcels clash in a location known as the front. Using blue water (cool air) and red water (warm air), you will see the ways in which frontal boundaries are formed between two different air masses.
Difficulty: Average
Time Required: 10 minutes or less
Here's How:
- Fill 1 measuring cup with warm water (from the tap is fine) and add a few drops of red food coloring so that the water is dark enough to clearly see the color. Do not make the water so dark that it is almost black!
- Fill the 2nd measuring cup with cold water from a faucet and add a few drops of blue food coloring.
- Stir each mixture to evenly disperse the coloring.
- Cover a table top with towels or plastic to protect the surface. Have paper towels handy in the event of a spill or leak.
- Inspect the top of each baby food jar to ensure there are no cracks or chips in the tops. Place one jar upside down on the other jar to ensure that they are an exact match. If the jars are not meeting exactly, you will end up with water everywhere!
- Now that you have inspected both jars, fill the first jar with cool water until it is almost overflowing. Fill the second jar with the warm water until is almost overflowing. Make sure your warm water jar is easy to touch and not too hot!
- Place the index card or plastic coated paper on the top of the warm water jar and press down around the edges of the jar to make a seal. Keeping your hand flat on the paper, slowly turn over the jar until it is upside down. Do not remove your hand. This step may take a little practice and some spilling of water is normal.
- Move the warm water jar over top the cold water jar so that the edges meet up. The paper will act as a boundary between the layers.
- Slowly remove the paper once the jars are stacked on each other. Pull gently while keeping your hands on the two jars. Once the paper is full removed, you will have a front. Now let’s see what happens when the two jars are moved.
- Keeping one hand on each jar, lift the two joined jars and slowly turn the jar to one side while holding the center together. You definitely need to do this over a sink or protected area because the potential for the jars to slide is great. Remember, the jars are not sealed together in any way. You have to hold them together carefully!
- Now, watch as you see the blue water (colder and more dense) slide underneath of the warmer water. This is the same thing that happens to air! You have just created your first weather front!
Tips:
- No special precautions are needed to complete this experiment. You may find that you can use various types of jars to complete this weather experiment. Substitutions are encouraged. Please be aware that this can become a very messy experiment if the jars get knocked over and some of the colored water will always spill. Protect your clothing and surfaces from the food coloring as stains may be permanent.
What You Need:
- 2 identical baby food jars (no lids needed)
- plastic coated heavy paper or an index card
- blue food coloring
- red food coloring
- water
- 2 measuring cups with pour spouts
- spoon
- paper towels
