Oceanic Circulation: What Keeps the Ocean in Motion?

Overview

Why is the ocean vital to our planet? There are many reasons, but one important one is that the ocean is a major player in regulating our weather and climate through currents. In this lesson plan, your students will model ocean currents with cups, water, and food coloring, and explore how temperature and density differences set deep ocean waters in motion to create a global oceanic circulation system.

NGSS Alignment

This lesson helps students prepare for these Next Generation Science Standards Performance Expectations:

• MS-ESS2-6. Develop and use a model to describe how unequal heating and rotation of the Earth cause patterns of atmospheric and oceanic circulation that determine regional climates.

This lesson focuses on these aspects of NGSS Three Dimensional Learning:

Science & Engineering Practices	Disciplinary Core Ideas	Crosscutting Concepts
Developing and Using Models. Develop and use a model to describe phenomena. Planning and Carrying Out Investigations. Collect data to produce data to serve as the basis for evidence to answer scientific questions or test design solutions under a range of conditions. Analyzing and Interpreting Data. Analyze and interpret data to provide evidence for phenomena.	ESS2.C: The Roles of Water in Earth's Surface Processes. Variations in density due to variations in temperature and salinity drive a global pattern of interconnected ocean currents. ESS2.D: Weather and Climate. The ocean exerts a major influence on weather and climate by absorbing energy from the sun, releasing it over time, and globally redistributing it through ocean currents.	Energy and Matter. Within a natural or designed system, the transfer of energy drives the motion and/or cycling of matter. Systems and System Models. Models can be used to represent systems and their interactions—such as inputs, processes and outputs—and energy, matter, and information flows within systems. Scale Proportion and Quantity. Time, space, and energy phenomena can be observed at various scales using models to study systems that are too large or too small.

Materials

Materials per group of 3–4 students:

• Plastic cups, 9 oz. (2 of the same size)
• CD
• Laminated paper or stiff plastic sheet; available from Amazon.com. Plastic strips cut from the lid of clamshell boxes for fresh produce also work well.
• Food coloring (dark colors such as blue and green work better than light colors)
• Hot water
• Ice water
• Spoon for mixing
• Small flashlight
• Immersion thermometer; available from Amazon.com
• Aluminum tray
• Smartphone with a sensor app such as phyphox, available for free on Google Play for Android devices (version 4.0 or newer) or from the App Store for iOS devices (iOS 9.0 or newer).
  Note: Phyphox does not support the light sensor on iOS devices. If you need the light sensor, you have to use Android devices for your experiment. Note that on some devices the light sensor is only updated when there is a coarse change of illuminance. This means that if the light intensity does not change or only changes slightly, the sensor appears to not record any data. The recording will continue once the light intensity changes again. If your experiments allows, it helps to wiggle the phone or the light source (e.g. flashlight) slightly to induce minimal reading fluctuations and keep the sensor active.

Materials for teacher preparation and demonstration:

• Scissors
• World map or globe
• Plastic cup
• Food coloring
• Teaspoon