Oceanography
Ocean Water and Currents
Name: ________________________________
Period: __________
Date: _____________
Introduction
An ocean current is a continuous, directed movement of seawater generated by the forces acting upon this mean
flow, such as breaking waves, wind, Coriolis effect, temperature and salinity differences, with tides caused by the
gravitational pull of the Moon and the Sun. Depth contours, shoreline configurations and interaction with other
currents influence a current's direction and strength.
Ocean currents can flow for great distances, and together they create the great flow of the global conveyor
belt which plays a dominant part in determining the climate of many of the Earth’s regions. Perhaps the most striking
example is the Gulf Stream, which makes northwest Europe much more temperate than any other region at the
same latitude. Another example is Lima, Peru where the climate is cooler (sub-tropical) than the tropical latitudes in
which the area is located, due to the effect of the Humboldt Current.
Purpose
The purpose of this activity is to investigate ocean currents using NOAA’s website.
Directions
1. Go to the following website, to answer the questions below.
http://oceanservice.noaa.gov/education/pd/oceans_weather_climate/media/ocean_and_wind_currents.swf
a. Click on the “Ocean Current” animation button at the bottom of the screen. You see the general
direction of the currents in the ocean. Draw arrows on the blank map showing the direction of the
currents, in all the ocean water.
b. Now click on the “Wind Current” animation button at the bottom of the screen. You will see the
general directions of the wind patterns around the world. Draw arrows on the blank map showing
the direction of the winds.
1. Go to the following website, http://oceanworld.tamu.edu/students/currents/index.html to answer the
questions below.
a. On the first slide, what current is that ship on in the panting? ___________________________
b. What are the two divisions of ocean currents?
c.
What properties of the ocean water does the climate control?
d. What type of current affects 20% of the ocean’s total volume?
e. What’s the name of the first space mission that allows scientists to use ocean topography?
f.
What does this space mission do to make studying the ocean easier?
g. What creates winds in the atmosphere? How does this work?
h. When meteorologists or people in general describe winds and their direction, what is a general rule
of thumb?
i.
What is the Coriolis effect?
j.
Describe the concept ‘pressure gradient’.
k. What is an Ekman spiral?
l.
What are gyres?
m. What are trade winds?
n. Why does a wind-driven current not flow in the same direction as the wind that causes it?
o. Why do subtropical gyres (pronounced jires) rotate clockwise in the Northern Hemisphere and
counterclockwise in the Southern Hemisphere?
p. Why are temperature and salinity the two most important tracers of water masses?
q. What are the factors that affect coastal currents but not deep ocean currents?
r. Why are the deepest water masses in the oceans formed at high latitudes? Why are they not formed in the
Indian and North Pacific Oceans?
Review
s. Go to the following link and take the provided quiz,
http://oceanworld.tamu.edu/students/currents/currents_quiz.htm. Score: ______________
t.
Go to the following linke and take the provided quiz,
Score: _______________
http://highered.mheducation.com/sites/0073376701/student_view0/chapter9/multiple_choice_quiz
.html.