Experiments with KVRR Meteorologist Scott Sincoff: Cold Convection Current

Fun and Easy Science Experiment

This week, Meteorologist Scott Sincoff worked with Ben Franklin Middle School Science Teacher Barry Olson to create a convection current with cold water.

What you need for the experiment:

• Cold water
• Room temperature water
• Food coloring
• Large tank with a barrier

How to conduct the experiment:

We’re going to take a look at how convection currents work in a liquid. They operate in liquids and gases. We’re going to focus on liquid water in this demonstration.

We have some room temperature water at 22°Celsius in one section of the tank. We have some cold, colored water at about 5° Celsius which we will pour into the second section of the container.  Now as we pull the gate up, we’re going to see the cold water move its way into the room temperature water. The cold water is going to stay on the bottom and move across the tank. As it moves across the tank, it’s going to push the room temperature water up above it.  When the cold water reaches the other side, it will go up and then circulate back down to the bottom returning back across in the other direction. We will eventually have two distinct layers; one being cold, and the other warmer.  This is how we can show a convection current in liquids.