CAMEL
Module #10 - Ocean Circulation Simulation (LAB)
Module Title
Summary
Short Description
Ocean Circulation Simulation: So Far, So Great
In this lab, students learn how ocean dynamics work.
Oceans affect or influence just about all life on Earth. It
is the special principles of water, in particular its density,
that make it possible for oceans to circulate. Wind also
acts as an important partner. While density impacts
underwater currents, wind drives surface currents.
How do oceans work? We see their ebb and flow, but
what causes this enormous movement of water that
influences the globe in many ways? Through a hands-on
experiment, students learn the basic principles that cause
ocean motion, that drive rising, sinking, and transport in
the real ocean.
Image
Source: http://science.nasa.gov/science-news/science-at-nasa/2004/05mar_arctic/
Learning Goals
Context for Use
Description and Teaching
Materials
Students will learn the following:
 To understand water dynamics - the ability of water
to travel great distances, horizontally and vertically
 To create different water masses and see how they
interact in a mini-ocean tank
 To interpret the basic principles that cause motion via
experimentation that simulates the varying properties
of water as well as wind
The format suggested for this lesson is a lab. It’s a hands
on experiment that should be held in a laboratory setting
- or, at the very least, a place where proper precautions
are taken (i.e. using plastic drop cloths in the event of a
spill). The lab also requires access to electrical outlets.
Description and Teaching Materials:
The structure and primary components of this lab lesson
is sourced from Columbia University’s Earth
Environmental Systems Climate (EESC) course, in
particular Lab 5: Ocean Circulation.
The following is introductory information intended to
provide students unfamiliar with oceans a basic
background in order to understand and perform the lab.
I. Introduction
The oceans are dynamic – water travels great distances,
from the Atlantic to the Pacific, from shallow surface
waters down to the deepest, darkest trenches and back up
again. Understanding what drives ocean circulation is
important because it influences marine ecosystems and is
strongly linked to earth’s climate. In this experiment,
students will create different water masses and see how
they interact in a mini-ocean tank. The basic principles
that cause motion here are the same as those that drive
rising, sinking, and transport in the real ocean.
A. Properties of water (H2O)
Water is a really special substance. It can hold a lot of
heat, is good at dissolving things, and is essential for life.
The density of water is a measure of how much mass is
contained in a certain volume. In other words, it’s the
mass/volume ratio, measured, for example in grams per
cubic centimeter). In the ocean, density is controlled by
both temperature and salinity. Warmer waters are less
dense because the individual water molecules have more
energy, bounce off each other, and create more space
between molecules. This means that for a certain
volume, there is less mass. Salinity is a measure of how
much material is dissolved in water – salts, mostly. Salty
water is denser than fresh water (pure H2O) because by
fitting in between the water molecules, dissolved salts
add mass without increasing the total volume. Also, this
dissolved material is often charged (positive or negative).
Because water is also charged (or “polar”), these
molecules are pulled towards each other – this makes
seawater denser, because more material is packed into a
certain volume.
Water density is important for ocean circulation because
dense water sinks.
B. Wind
Surface currents are often driven by wind. Moving air
exerts a frictional force on the water surface beneath it,
basically dragging it along. Winds influence surface
water currents across the globe in many ways that have
an impact on ecosystems, fisheries, and marine
transportation.
II. THE EXPERIMENT:
Using the given materials (water tank, beakers, salt, ice,
food coloring, hair dryers), students design their own
experiments. They have three “drivers”: salinity,
temperature, and wind.
The Experiments Goals are:
1) Create a stratified ocean, with distinct surface,
intermediate, and deep-water masses.
2) Cause circulation/motion using density and/or wind
(measure velocity during your experiment using
stopwatches & rulers).
3) Carefully record your experimental procedure,
observe what happens in your tank, and describe/explain
it in a lab report.
A. PROCEDURE
Students describe the experiment they constructed. What
were the initial water mass properties? Describe them in
terms of salinity (estimated) and temperature (measured
using thermometers). In what order did they add them,
and how did they measure the mixing / motion? How
did students apply wind?
B. RESULTS
Students illustrate what they saw in a brief paragraph and
drawing(s). On the drawings, label water masses and use
arrows to indicate flow direction. Report any measured
velocities or other measured quantities in a table/graph.
Draw qualitative final vertical profiles of salinity,
temperature, and density of the tank (halocline,
thermocline, and pycnocline).
C. DISCUSSION:
 Where do the processes simulated occur in the real
ocean?
 How do ocean tank conditions differ from natural
conditions? Are there any important missing forces
or drivers?
 How did water mass velocities vary, and why?
 Did the tank behave as expected? Discuss any
differences between expectations and observations.
D. CONCLUSION:
Why is what was learned from this experiment
important?
E. LAB TIPS
 Write the lab report in the form: Introduction,
Procedure/Method, Results, Discussion, Conclusion
 Read the lab instruction carefully and be prepared
before coming to the lab:
-

You have to understand the
fundamentals of ocean circulation
before coming to the lab
Think about how to create different
water masses before you come to the
lab!!
Bring with you a camera,
stopwatch/cell phone and maybe also a
ruler/scale
Don’t forget to make sketches!
Take care when handling the thermometer
(mercury!)
Below are the links for source material and resources:
 EESC course page for Ocean Circulation lecture and
lab: https://courseworks.columbia.edu/cms/
Handouts and Directions:
 Lab instructions
Background Information for instructors/TAs:
Instructors/TAs may find it useful to refer to the
following lectures for background information from
EESC Spring 2010:


General Circulation of the Ocean (Ting)
Ocean: Wind Driven Circulation and the Gulf Stream
(Ting)
Equipment/Supplies:
 Water tank
 Beakers
 Salt
 Ice
Teaching Tips and Notes
Assessment
References and Resources
 Food coloring
 Hair dryers
See background information for instructors/TAs.
Students summarize their findings in a lab report.
All resources cited in the description of the course.