Download Ocean Motion Teacher Guide 5

Ocean Motion
Teacher Guide
5
Patterns of Energy Balance
Cold are the feet and forehead of the earth,
Temperate his bosom and his knees,
But huge and hot the midriff of his girth,
Where heaves the laughter of the belted seas,
Where rolls the heavy thunder of his mirth
Around the still unstirred Hesperides.
The Belted Seas, Arthur Colton
Ocean Motion
Teacher Guide 5
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Lesson Objectives
Performance Tasks
To demonstrate an understanding of
ways to manipulate data collected using
a specified measurement protocol.
Identify graphs used to manipulate data.
To use the human body as a model to
understand energy balance in the Earth
system.
Identify parts of the energy-balancing
mechanism of the Earth that mimic the
human body.
To demonstrate an understanding of
patterns of the diurnal heating and
cooling cycle of the atmosphere.
Compare patterns of diurnal heating and
cooling of the atmosphere to predictions of a
Daily Metabolism model.
To manipulate a computer model to
show the fluctuations of solar energy
received by Earth.
Determine when solar intensity is highest and
lowest at various sites on Earth.
To read a computer model to show
circulation of warm and cool ocean
surface currents.
Identify specific patterns from a computer
model of sea surface current and
temperature data.
Materials:
Student Guide (downloadable pdf file)
Student worksheet (downloadable pdf file)
Internet access
Time:
90 minutes
Introduction
Scientists are concerned about the global warming that
would result from a global imbalance in the flow of
energy. Oceans play an important role in forecasting
the consequences of an energy imbalance. An
understanding of the flow of energy and the balance of
energy at the ocean’s surface will help you interpret
patterns in Sea Surface Temperature data images.
Ocean surface water a few meters deep has the same
heat capacity as the atmosphere above it. It takes
nearly four times as much energy to increase the
temperature of one kilogram of seawater by one degree
Celsius than to do the same with one kilogram of air.
In addition, one kilogram of air (at standard
temperature and pressure) has almost 800 times more
volume than 1 kilogram of seawater. The same heat
energy will cause the same temperature change for
either 3,200 cubic meters of air or one cubic meter of
seawater. Because the ocean surface is always in
contact with the atmosphere, these numbers mean that the ocean surface can act as a very
effective heat storage medium for the atmosphere. Small changes in ocean surface
temperature can be caused by large exchanges of energy with weather systems.
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The state of the ocean and the atmosphere changes greatly throughout the seasons of the
year–just like your body experiences diet and activity level changes during Summer, Fall,
Winter and Spring. At any one location and time, incoming and outgoing energies do not
have to balance. Data from the ocean surface show that the state of the ocean surface
undergoes changes that may not be the same from one year to the next. This is not a
concern as long as there is overall energy balance for the whole globe over the years.
Specific heat of air 1050 J/(kg K), specific heat of seawater 3850 J/(kg K)
Based on PV=nRT, mass of air = nx6.023x10 23x(0.8x28+0.2x32)x1.67x10-27, density of
seawater=1025 kg/m3
2
Engage: Preconceptions Survey
Students are asked to take an online
consisting of nine questions. When
they submit their responses online, a pop-up window appears that shows the correct
response to each question and provides additional, clarifying information. All nine questions,
the correct responses and additional information are provided below.
Engagement activities such as this one are typically not graded. Student responses to this
survey will help determine how much accurate information they already know about
patterns of energy flow.
TRUE or
FALSE
STATEMENT
FALSE
The sunlight energy absorbed by Earth is equally absorbed by
land and oceans.
Oceans make up 70% of the Earth's surface and their darker color (low
reflectivity or albedo) guarantee that the oceans will take up most of the
incoming solar energy. In addition, oceans are fluid and so the energy in
the ocean tends to mix to depths. Heated soil is hot only at the surface
and the heat does not penetrate far downwards. Water has a high
specific heat that is five times higher than soil. A kilogram of water
requires 5 times more energy than soil to increase its temperature by
one degree. So even though most ocean water is very cool, this does
not mean it is not absorbing solar energy.
FALSE
In July, the Earth is closest to the Sun.
The Earth is closest to the Sun in January. Most of the seasonal change
that we see is due to the tilt of the Earth on its axis of rotation. The axis
is tilted at 23 degrees and it stays pointed in the same direction towards
Polaris, the North Star. During winter in the Northern Hemisphere, the
Northern Hemisphere is tilted away from the sun. Six months later at the
other side of the Earth's orbit, the Northern Hemisphere tilts towards the
sun and it experiences summer.
3
TRUE
Sea surface temperature and currents are used to make
forecasts of fishing conditions in the ocean.
Each species of fish seeks out waters in a temperature range that suits
its metabolism and biochemistry. Fishermen can access fishing forecasts
based on maps of surface temperature, currents, phytoplankton and
other environmental conditions to track down specific fish species (e.g.,
marlin, tuna).
4
FALSE
The lowest sea surface water temperature is 0 °C.
Salty water freezes at -2 degrees C.
1
2
Ocean Motion
Teacher Guide 5
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5
6
7
8
9
TRUE
Most of the ocean water at the equator is near the freezing
temperature.
Most of the water on the equator lies deep below the surface where it
receives no sunlight, and warm water tends to rise to the surface
because of its lowered density.
FALSE
Satellites in space measure the temperature of ocean water by
its color: light blue is warm and dark blue is cool.
Temperature does not affect the color of water. Mapped ocean images
sometimes use colors to represent the temperature of the surface
waters, but these colors do not represent the true colors seen in nature.
FALSE
At the equator, the sea surface temperature does not vary
seasonally in a regular cyclic pattern from year to year.
The sea surface temperature at the Equator shows repeating cyclic
variation at most locations. Sea surface temperatures depend on ocean
currents as well as the sun. On the Equator the length of day is always
the same (12 hours) and the Sun passes overhead twice during the
year, near March 21 and September 21.
FALSE
Water is clear so sunlight penetrates the water surface and
keeps the water warm deep below the surface.
Water is blue. Water absorbs red light strongly and even blue light does
not penetrate far into the water. Water warmed below the surface
becomes less dense and so would rise upwards. Below the surface, it
becomes very dark as you go deeper.
FALSE
Phytoplankton, a plant-like marine organism that grows near the
surface of the ocean, has its highest density when the sea
surface water is warmest.
The data does not show a consistent relationship between the time of
maximum temperature and chlorophyll concentration in the ocean.
Chlorophyll concentration depends on nutrients and chemicals available
in the seawater. Like many marine organisms, species of phytoplankton
grow best within a certain range of temperatures and not necessarily at
the highest temperature.
100
Overall Score (%)
Explore: Measurement Protocol and Data Manipulation
Basic Data Gathering and Processing
Hydrologic science, an important interdisciplinary science dealing with the occurrence,
distribution, and properties of water on Earth, is key to understanding and resolving many
contemporary, large-scale environmental issues. Accurate data collection and proper
manipulation of data are critical to better understand ocean surface processes.
Scientists realize they can never make a perfect measurement; their goal, is to come as
close as possible within the limitations of the measuring instruments and established
protocols (i.e., set of rules to be followed for every measurement). Science cannot be done
"on automatic pilot"—scientists have to think about what they are doing. Therefore,
protocols are established and followed to insure as much accuracy as possible.
Ocean Motion
Teacher Guide 5
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Suppose you wish to measure the surface temperature of the ocean, a river or a lake. First,
you would decide on a measurement protocol to insure (1) your measurements are taken
under similar (or known environmental) conditions, (2) every effort is made to eliminate
mistakes (illegitimate errors) and reduce systematic (biased, one-sided) errors. It is
assumed that random (unbiased, two-sided) errors cause the dominant variations in
your data.
Protocol to Measure Water Surface Temperature
_________________________________________________________________
Determine:
•
•
•
•
•
•
•
Location(s)
Time of day, day of year
Calibration of thermometer
Depth of thermometer in water
Time of thermometer in water
Weather conditions
Water temperature
Data Collection:
Assume that 15 temperatures were collected using the above protocol.
Data Manipulation:
Each of the following five manipulations may help to better understand the data collected.
1. Graph Data: The data points make a pattern that seems to be level. If the points
showed a systematic trend rising or falling from left to right, it would suggest that the
“true” value being measured was systematically changing during the measurements. In this
case, the protocol should be redesigned.
2. Expand Graph Scale: To see the variations in the data more clearly, expand
(magnify) the data scale. The data points look different but correspond to original
values graph.
3. Compute the Mean: Add all measurements and divide by the number of points (15).
The mean value is shown by the red line in the figure.
4. Compute the Differences from the Mean: Compute the difference between each data
point and the mean value. This will be used to estimate the variation in this set of
measurements.
5. Compute the Standard Deviation: Use all the differences to compute the standard
deviation (s) of the data set. The red lines show the limits of the [mean + s] and
[mean – s]. Note that 10 data points lie between these limits and 5 lie outside:
Within limits: 10/15 = 2/3 = 67% of the data set
Outside limits: 5/15 = 1/3 = 33% of the data set
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Teacher Guide 5
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Try the Following Activity:
Determine which of the following five graphs represent each of the five data manipulations
listed above. The data points are shown on the x-axis, temperature in degrees Celsius on
the y-axis, and the red x’s are the temperature for each data point.
Examine the five graphs below and correctly label each graph with one of the five titles
listed below.
1. Data Points
2. Data Points Expanded
3. Mean or Average Value ( = 21.56)
4. Differences from the Mean
5. Standard Deviation ( = 1.950)
Title: Differences from the
Mean
Title: Data Points
Title: Data Points Expanded
Title: Mean or Average Value
Title: Standard Deviation
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More Challenging: Standard Deviation Computation
Here is an example of how the mean and standard deviation are calculated. The data
values (27.4, 26.5, 28.1, …) are arbitrary values:
1
2
3
4
5
COLUMN
TOTAL
Data
XI
27.4
26.5
28.1
27.6
26.9
Difference
XI-XM
(27.4-27.3)=0.1
(26.5-27.3)=-0.8
(28.1-27.3)=0.8
(27.6-27.3)=0.3
(26.9-27.3)=-0.4
5
5
 X I  136.5
(X
I 1
Mean
XM
136.5
 27.3
5
Squared Difference
(XI-XM)2
(0.1)2=0.01
(-0.8)2=0.64
(0.8)2=0.64
(0.3)2=0.09
(-0.4)2=0.16
I 1
Standard
Deviation s
I
 X M ) 2  1.54
1.54
 0.5
5
The mean and the standard deviation are related in a very important way. For a given data
set, the mean is the single value that minimizes the standard deviation of the data. Choice
of any value other than the mean for calculating the standard deviation yields a larger
standard deviation. If, for example, you replace the mean value 27.3 with 28.0 everywhere
in the above calculation, you will find that the standard deviation increases. In this sense,
choice of the mean value as the “best” value to represent a dataset is justified by the fact
that it deviates least from the other members of the dataset.
The following is a new dataset. Practice the calculation of mean and standard deviation
values:
Column
1
2
3
4
5
6
7
COLUMN
TOTAL
Data
XI
4.73
4.65
4.82
4.70
4.69
4.83
4.77
5
X
I 1
Mean
XM
I
Difference
XI-XM
-0.01
-0.09
0.08
-0.04
-0.05
-0.09
0.03
Squared Difference
(XI-XM)2
0.0001 OR 1.0E-4
0.0081 OR 8.1E-3
0.0064 OR 6.4E-3
0.0016 OR 1.6E-3
0.0025 OR 2.5E-3
0.0081 OR 8.1E-3
0.0009 OR 9.0E-4
5
(X
 ____ 33.19
I 1
4.74
Standard
Deviation s
Ocean Motion
I
 X M ) 2  ____ 0.0277
0.063
Teacher Guide 5
7
Explore: Energy In = Energy Out
How can an analogy to the human body be used to better understand energy in the Earth
system?
Energy balance is a familiar topic to most people because it relates directly to their health.
Your body maintains an energy balance:
Energy In = Energy Out + Energy Stored
The above formula illustrates energy conservation—all the energy has to “go” somewhere.
It cannot just disappear. Humans eat food which provides energy (calories) for biochemical
processes necessary for life as well as for heat that is lost through radiation, conduction,
convection and evaporation processes. The flow of blood in the body is regulated to control
temperature and increase or decrease body heat. If too much food is consumed, it is
eliminated as waste or stored as fat in the body. Ideally humans do not want to eat so
much that body fat increases because increased weight stresses many important systems of
the body. To be sustainable over long periods of time, the body cannot either continuously
gain or lose stored energy (fat). The net energy stored over long time periods should be
zero:
Energy In = Energy Out
In the chart below, complete the following analogies that compare the energy balance of the
body to that of the Earth to help you better understand energy balance in Earth systems.
Energy
Human Body
Earth
Source of Most Energy
Food
Sun
Ways to use the energy
Exercise, work, heat
loss
Winds, storms, currents,
photosynthesis
Ways to store the energy
Fat accumulation
Latent heat, ocean temperature,
fossil fuels
Ways to control
temperature
Adjustment of blood
circulation, sweat,
clothing
Air and water circulation
Explore: A Study of Air Temperature
What do data reveal about daily energy cycles in the Earth system?
To investigate daily energy cycles, you will begin by examining air temperature data
collected in Washington, DC on July 4–5, 2005. On July 3, the Earth is farthest from the
sun—94,500,000 miles (in the first week of January, Earth is closest—91,400,00 miles).
Many of the details that you will learn about this daily energy cycle will apply to the yearly
cycle of ocean surface temperature as well. The daily cycle occurs because Earth rotates
once on its axis every 24 hours. The yearly seasonal cycle occurs because Earth is tilted on
its axis towards Polaris, the North Star. As Earth moves around the Sun, this tilt remains
constant and the Northern Hemisphere experiences winter (i.e., Earth’s axis tilted away
from the Sun) and summer (i.e., Earth’s axis tilted towards the Sun).
Ocean Motion
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The graph below represents outside air temperature for July 4–5, 2005 in Washington, D.C.
Read the graph and answer the following three questions.
1. Determine the maximum temperature and the time and date it occurred.
Max Temp: 30.2oC
Time: 5 pm
Date: July 4
2. Determine the minimum temperature and the time and date it occurred.
Min Temp: 21.9oC
Time: 8 am
Date: July 4
3. Determine the temperature range. The temperature range was 8.3 °C (30.2 - 21.9).
During the entire 24 hour interval, the Kelvin (absolute) air temperature was relatively
constant:
30.2oC (max temp) = 30.2 + 273.15 = 303.35oK
21.9oC (min temp) = 21.9 + 273.15 = 295.05oK.
Measured on this scale, the Kelvin temperature of the air changed by less than 3% over
24 hours:
303.35  295.05
 100%  2.8%
295.05
The energy radiated by a substance or object depends directly on this Kelvin temperature.
Objects with a higher temperature radiate more. Assuming that the nearby ground surfaces
have temperatures similar to the air temperatures, it can be concluded that during the 24
hour period, the electromagnetic energy radiated around the site of the Washington, D.C.
weather station site was fairly constant.
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The following graph shows solar radiation (intensity in Watts per square meter) received at
the Washington, D.C. weather station. Note: The solar radiation is NOT constant throughout
the day. The incoming solar energy reaches a high peak around noon and is zero between
8:30 pm and 6 am (when Washington D.C. is not receiving light from the Sun).
4. Compare the two graphs (Solar Radiation, above and Outside Temperature, on page 9)
and describe what happens to the air temperature between 2 pm and 8 pm and solar
radiation steadily decreases.
Air temperature continues increasing until 5 pm when it starts decreasing. Solar radiation
decreases continuously during these 6 hours.
5. Why are there no values for solar radiation between 8:30 pm and 6 am? Describe what
happens to the air temperature during this time.
There are no values for solar radiation because there is no solar energy (i.e., the sun has
gone down). Therefore, the air temperature continues to decrease at a very steady rate.
Why Is There a Time Delay?
Based on the graphs, it is evident that there appears to be a delay in response to the Sun’s
energy. Air temperatures continue to rise and remain steady for hours after solar radiation
reaches its peak.
The air temperature reaches its peak near 5 pm. Why? To investigate this question, you will
use our simple body energy balance model—call it the “daily metabolism” model. We
expend energy constantly during each 24 hours, even when we are sleeping but absorb
energy only when we eat meals or snacks. To make a direct comparison to air temperature,
it will be assumed (perhaps unrealistically) that the nourishment peaks at noon—lunchtime.
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Use the following Daily Metabolism Model
Start with 9 units of energy (Total Energy) in the body at 1 am. By 2 am, no additional
energy is absorbed; however 1 unit is spent, leaving 8 units of energy. Continue filling in
the model’s Total Energy values:
ET (2AM) = ET (1 AM) + EA (1 AM) – EU (1AM) = __8__
ET (3AM) = ET (2 AM) + EA (2 AM) – EU (2AM) = __?__
Daily Metabolism Model (Midnight to Noon)
Time of Day
AM
1
2
3
4
5
6
7
8
9
10
11
Noon
PM
Midnight
1
2
3
4
5
6
7
8
9
10
11
Energy
Absorbed
(EA)
0
0
0
0
0
0
1
1
2
3
3
4
3
3
2
1
1
0
0
0
0
0
0
0
Energy
Used (EU)
Total Energy
(ET)
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
9
8
7
6
5
4
4
4
5
7
9
12
14
16
17
17
17
16
15
14
13
12
11
10
Explain: 6. When does absorbed energy reach its minimum? Its maximum? When does total energy
reach its minimum and its maximum?
Daily Metabolism
Energy Absorbed (EA)
Total Energy (ET)
Time
Minimum
6 pm - 6 am
6 am - 8 am
Maximum
12 Noon
3 pm - 5 pm
7. How is the behavior shown by this model similar to, or different from, the air
temperature situation?
Just like the outside temperature graph, the total energy reaches its maximum in late
afternoon and decreases steadily at night.
Ocean Motion
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Explore: The Yearly Cycle
How does solar energy received by Earth change throughout the course of a year?
Extend your study of the yearly solar energy cycle received by Earth with an online solar
energy animation. As you cycle through a year, changes in temperature are shown as color
changes on a world map.
Make a Prediction: Before you view the solar energy animation guess, which month the
solar intensity will be greatest and which month will it be the lowest, for your hometown.
1. In what town/city do you live? _________________________________
2. During which month do you think solar intensity is greatest at
your home? ______________________________________________________
3. During which month do you think solar intensity is lowest at
your home? ______________________________________________________
Link to the Solar Energy Animation , pictured below. (Note: Because of the file size, give the
web page time to download its images.) Manipulate the computer model until you feel
comfortable with it. Then return to this page for further instructions.
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4. Use the computer model to estimate the energy intensity at your home and at the
Equator at the start of each month during the year. Use the drop-down menu to select
months January through December; note the color changes on the map; and use the legend
below the map to determine energy values.
Note: The colors shown on each map may be used to determine the total energy (i.e.,
ignoring atmosphere absorption/reflection) provided by the Sun within a ground area of
1square meter for the date shown. In the image, shown on January 1, Washington D.C. lies
in the middle of the dark blue color on the map, which means on January 1 the Sun
provided the Washington D.C. region approximately 0.3 x 10 8 J/m2 during a day. On a very
clear day, approximately 20% of this passed through the atmosphere.
Sample values for Washington D.C. and the Equator are shown below.
Intensity
Jan
1
Feb
1
Mar
1
Apr
1
May
1
Jun
1
Jul
1
Aug
1
Sep
1
Oct
1
Nov
1
Dec
1
Wash.,
D.C.
0.32
0.44
0.6
0.76
0.96
1.02
1.06
1.0
0.84
0.6
0.4
0.36
0.72
0.84
0.88
0.92
0.92
0.88
0.84
0.92
0.92
0.92
0.84
0.84
Equator
Explain: Use the values you recorded in the table to answer the following three questions:
5. In which month was solar intensity the greatest at:
Washington, D.C.? July
Equator? Apr, May, Aug, Sep, Oct
6. In which month was solar intensity the lowest at:
Washington, D.C.? January
Equator? January
7. How accurate were your earlier predictions?
Explore: Sea Surface Temperatures
How does solar radiation affect sea surface temperatures?
In this activity, you will examine sea surface environment data that are superimposed on a
map and incorporated into a computer model that can be manipulated. Click on the
Sea Surface Environment model, pictured on the top of page 14; set the date to November
1981; and set the parameter to temperature.
Observe the map generated and respond to the following 5 questions.
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The colors of the image represent sea surface temperatures measured over the week of
November 8, 1981. It is important that students are able to accurately read maps: The top
of the map is North, the bottom is South, the left is West and the right is East. A natural
coordinate system (i.e., near spherical objects) employed for planets and moons uses
angles of longitude and latitude to identify locations. The numbers across the top and
bottom of the map give longitude values. The numbers on the right and left side of the map
indicate latitude numbers. At the Equator, latitude = 0o, at the North Pole, latitude = 90o
(or 90N) and at the South Pole, latitude = -90o (or 90S).
1. What patterns do you see in the November 1981 Sea Surface Temperature data (SST)?
Temperatures vary with latitude.
2. Where are the water surface temperatures coldest?
Temperatures are coldest near both poles.
3. Where are the water surface temperatures warmest?
Temperatures are warmest near the Equator.
4. Do you see regions where cool surface water moves into latitudes where warm surface
water dominates?
Western coasts of South America and Africa
5. Do you see regions where warm surface water moves into latitudes where cool surface
water dominates?
Scandanavia, north of Europe
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Next, return to Sea Surface Environment data visualizer.
• The Click-On-Map Data, selector, determines the type of data displayed when you click on
any 5o x 5o ocean site on the map. Available options are a graph or a table of median
parameter data for the site during all the available years.
• Set the Click-On-Map Data option to Graph and click anywhere on the ocean map. A time
series graph will appear showing you how the sea surface temperature at that site varied
over the years. For example:
The graph above shows sea surface temperature, at a selected site—near the Galapagos
Islands. Before proceeding with interpolation of any graph, including this one, it is
important to make certain that you understand what the x- and y-axes represent.
Answering the following questions correctly is critical to reading this graph accurately.
6. What is measured on the x-axis?
Time in years
7. What does each vertical line (blue) on the
graph represent?
One year
8. What is the range of the entire graph?
1981 – 2005
9. What does each horizontal dot on the graph
represent?
Month of the year
10. What is the month and year that data were
first shown on this graph?
November 1981
11. What is measured on the y-axis?
Temperature in oCelsius
12. What does each graduation on the y-axis represent?
.5 oC
13. The graph shows data that varies considerably from year to year. Complete the
following chart by identifying three years when sea surface temperature was highest and
three years when it was lowest:
Mean Sea Surface Data (95W – 90W, 0N – 5N)
Highest Temperatures
Lowest Temperatures
Year
1983
1987 or
1998
1985
1988
1992
Month
April
April
March
August
July/August
Temp oC
30.2
29.5
30.2
23.2
22.6
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August
23.3
15
A scientist would be interested in knowing whether other ocean sites, both nearby and far
away, would reach highest and lowest surface temperatures during the exact same years.
14. If during a certain year, many widespread sites experience the same unusually high or
low temperatures, there is good reason to look for the cause of such behavior. To study the
effect on other types of data and to see how the unusual temperatures affected the weather
of the region, complete an analysis of one more site off the east coast of North America.
Mean Sea Surface Data
Highest Temperatures
Year
Month
Temp oC
Lowest Temperatures
To develop a measure of how unusual, or normal, a data value may be, one needs some
measure of both. To quantify data values as normal or unusual, people often compute two
measures from their data:
• Mean—a weighted or unweighted average of data values
• Standard deviation—measures the scatter of data values with respect to the mean value
Elaborate: Currents that Circulate Warm and Cool Waters
When you examined the sea surface temperature map earlier, you were asked to identify
regions where cool water intruded into regions normally warm and warm waters intruded in
regions normally cool. One of the regions where cool water intrudes into a region of warm
water is in the Eastern Pacific, near the west coast of South America. The reason for this
intrusion is the flow of surface currents. Shown below is a Tropical Pacific Surface Currents
data computer model that uses OSCAR data showing ocean surface currents around October
15, 1992. The gray area on the right of the map shows part of the west coast of South
America. The white area, along the coast of South America, has no data. The arrows show
the direction of the currents and the current speed in meters per second.
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1. What speed do the following colors represent?
Magenta - 0 m/s
Darker blue - 0.3 m/s
Lighter blue - 0.5 m/s
2. What direction do the surface currents just south of the Equator appear to travel.
East to West.
3. Note in the southeast corner of the map a strong (blue) current flows along the coast of
South America. What is the direction of this current?
North and Northwest
The current moving up the western coast of South America is the Peru Current which brings
cool water from the South Pacific and Southern Oceans. The westward-moving current along
the equator is called the Pacific South Equatorial current. These currents are very important
for understanding the dynamics of El Niño.
These currents provide an example of the currents that circulate warm and cool waters and
mix the two. This circulation, like the body’s well-regulated circulation, provides important
climate control to moderate global temperatures.
Evaluation: Holistic Rubric for Grading Lesson
4
Expert
3
Proficient
2
Emergent
1
Novice
Responses show accurate identification of graphs used to explain
manipulation of sample data. Shows solid understanding of analogy of the
human body to explain energy balance in Earth system. Proficient
interpolation of graphs to show diurnal heating and cooling cycle of the
atmosphere. Proficient manipulation of computer model to read near realtime satellite data, and analysis of data is complete and accurate.
Responses show accurate understanding of models and analogies used to
explain scientific concepts and processes used in the lesson. Shows good
understanding of analogy of the human body to explain energy balance in
Earth system. Mostly proficient interpolation of graphs to show diurnal
heating and cooling cycle of the atmosphere. Mostly proficient manipulation
of computer model to read near real-time satellite data and analysis of data
are mostly complete and accurate.
Responses show partial understanding of models and analogies used to
explain scientific concepts and processes used in the lesson. Shows some
understanding of analogy of the human body to explain energy balance in
Earth system. Mostly proficient interpolation of graphs to show diurnal
heating and cooling cycle of the atmosphere. Somewhat proficient
manipulation of computer model to read near real-time satellite data and
analysis of data are partially complete and accurate.
Responses show very limited understanding of models and analogies used
to explain scientific concepts and processes used in the lesson. Shows
limited understanding of analogy of the human body to explain energy
balance in Earth system. Mostly proficient interpolation of graphs to show
diurnal heating and cooling cycle of the atmosphere. Limited or no ability to
manipulate computer model to read near real-time satellite data and
analysis of data are not complete.
Ocean Motion
Teacher Guide 5
17
Ocean Motion
Teacher Guide 5
18