Density Tanks

This lesson shows how to use density split tanks to demonstrate thermohaline circulation.

From https://www.flinnsci.com/

The purpose of this lesson is:

• To show students hot water rises & cold water sinks.
• To show fresh water rises and salty water sinks.

The students will understand how thermohaline circulation (difference between temperature and salinity) drive the Global Conveyer belt in the ocean’s. Cold, salty water from the poles sinks and heads toward the Equator. Warm, fresh(er) water from the Equator rises and heads towards the poles. Currents carry enormous amounts of energy and affect Earth’s climates.

This lesson helps to teach SEEd standards, 6.2.2/6.3.1/6.3.3.

Supplies needed:

• Split tanks
• Warm Water (in a gatorade bottle) – the small bottles tend to be the perfect size to portion out ahead of class and to prevent massive spills.
• Cold Water (in a  gatorade bottle)
• Red/blue food coloring ( 5mL)
• Stir stick
• Salt water ( in a gatorade bottle)
• Fresh water (in a gatorade bottle)
• Spill tray

Find the lab worksheet attached in the lesson documents.