Overview
Students will compare weather data for locations at
different elevations to discover the effect that elevation
has on temperature.
Objectives
Students will be able to:
 investigate how elevation affects the weather in a
particular region;
 determine the correlation between elevation and
temperature; &
 make basic predictions to how temperature changes
with elevation.

Time
One 45 minute class period.
Materials
Teacher Preparation
 LIMITED ACCESS: If technology resources
are limited, you can access the weather web site
before your class and print the weather data or display the
weather web site using a projector or television
screen.
 GRAPHING: Students will be creating a scatter plot
for this lesson. If you are new or not familiar with
graphing, please review the
Graphing Tips.
 Weather relatedtopics:

Procedure
Part 1: Elevation and Temperature
Begin by leading a brief class discussion with the
students by asking them if they can think of any
cities that are located at different elevations. If
students are not familiar with the terminology, it may
be useful to compare a mountain and sea level as an
example. After they mention several cities, ask them
what they think happens to the temperature as elevation
increases and decreases. Once they have discussed some
responses, ask them to think of a method to prove their
hypotheses. This
will spark their interest in the subject and get them thinking about
the relationship between temperature and elevation.
Optionally, you can divide the students in
pairs or small groups so they can share and discuss
their predictions with each other.
 Use a wallsize map of Ecuador to show the students the
locations in the table or distribute individual maps
to each of the students or groups of students. You might mention
that Ecuador was selected to serve as the example
country to demonstrate the relationship between
elevation and temperature because it has many cities
with vastly different elevations all located around
the same latitude and location. This is very important
because students should learn that the only way to
confirm the influence that elevation has on
temperature is to keep all of the other variables
constant. Therefore, any differences in the
temperature patterns can be attributed to elevation
since it is the only difference in the locations.
 NOTE: For the purposes of this activity, the effect
that latitude will have on the temperature for each the
locations is negligible because they are all within 2º
of the equator.
 After locating the cities, ask the students if
they can make any predictions about the weather for
any of the locations. You can organize the students in
pairs or
small groups so they can share and discuss their
predictions with each other, however each student
should be held responsible for answering each question.
 As an optional activity, lead a whole class
discussion after the pairs/small groups have
answered the questions. This can be
play an important part in assisting the students
elaborate their thoughts.
 Since these are real time weather readings, the
weather stations for each of the locations may submit
the current temperatures to the
weather web site at different times during the day,
and therefore you should only compare the high
temperature readings for today's forecast.
Part 2: Analyze the Data
The effect that elevation has on temperature can be
analyzed by using a scatter plot to graph the two
measurements. Scatter plots demonstrate a trend in the
data and are similar to line graphs in that they begin
by plotting different data points. However, the
difference is that each of the individual points are not
connected together with a line but rather a trend line
is added where approximately the same number of points
occur below the line as above it.
 The students can either use a spreadsheet program
(recommended) or create a graph to manually plot the
points. Students should label the xaxis in meters
from from 0 to 7,000m and the yaxis in Celsius from
15ºC to 35ºC.
 You may need to demonstrate how to add a linear
trend line to the scatter plot if many of the students
have never made one before. It is recommended that you
do not use the same elevation temperature data and you
should mention that a trend line will not cross every
point and that they should not connect the dots but
rather estimate where the line should fall so that
approximately the same number of points below the line
as above it.
 When explaining what a trend line is, it will be
helpful to mention that when most of the data points
are on or close to the trend line, this generally
means there is a close relationship between the data
points. On the other hand, if the data is all over
the graph and it is difficult to draw the trend
line, this most likely means that there is little
correlation between the two variables.
 Students should be able to determine the
approximate change in temperature for every increase
of 1,000m in elevation based on the graph. Their
answers will vary depending on the individual high
temperatures for the day but should be within the
range of four to seven ºC for every 1,000m in
elevation.
 The correlation coefficient corresponds to how
much the different data points are correlate. For
example, data points that have little or no
correlation will have a correlation coefficient close
to zero while data points that have a higher
correlation will be closer to one. In this example,
the lineal regression equation can be used to compute
the approximate temperature of a particular elevation
 value x.
 NOTE: If students used a spreadsheet program, it
should be able to automatically determine both the
correlation coefficient and linear regression
equation.
 Students can either estimate the approximate
temperatures at zero latitude for each of the
elevations or compute the temperatures using the
linear regression equation. As above, the answers will
vary slightly depending on the high temperatures of
the day.
 & 7. Students should be able to
calculate the temperature estimate however in both
cases their calculation will not be equal to the real
values for either Mt. Everest or the Bentley
Subglacial Trench. The reason for this is that they
are both located at different latitudes which has a
significant effect on their temperatures. The purpose
for these two questions is to provide the students an
opportunity to apply their knowledge from the previous
activity.
Part 3: Final Conclusions
 The students should have observed that the
temperatures from the locations in Ecuador decrease as
the elevation increased. Therefore, they should be
able to conclude that temperature decreases as
elevation increases and viceversa.
 Answers may vary however the each should be
similar to the following: Generally, a relationship
determined by comparing data from only a few locations or
from a very limited time period, such as one day in
this case, is vulnerable to shortterm changes and errors
and therefore may be unreliable.
 Answers may vary but they should be more than at
least two times, or double, the amount of data used
for this activity.
 Answers may vary.
Students might mention that they could collect more
temperature readings from other cities in Ecuador
and/or collect temperature readings over a series of
days or weeks and average the data.
 The reason why temperature decreases as
elevation increases is because air pressure similarly decreases
with elevation. As the
air pressure decreases, the air density also decreases
causing a decrease in temperature. In other words, as air molecules become more
spread out, their density decreases and the particles
move slower because they are packed into a larger
space. Conversely, as air pressure and density
increase, temperature increases as well because the
more particles move faster when packed into a smaller
space, thereby making it hotter.

Assessment
Make each student or cooperative group responsible for
their answers.
Student Activity
NOTE: The following
instructions also appear in Student
Activities.

Activity C3: Elevation
and Temperature 


Part 1: Elevation and Temperature
 Locate and mark the following locations on a map of Ecuador.
Location 
Latitude 
Elevation (m) 
High Temp. (ºC) 
Cotopaxi 
0 
5897 

Quito 
0 
2811 

Latacunga 
1 
2785 

Ibarra 
0 
2228 

Esmeraldas 
+1 
7 

Guayaquil 
2 
4 

 Which location do you think will have the highest temperature? the lowest?
Why?
HINT: the effect latitude will have on the temperature for each
of the locations is negligible because they are all within 2º of the equator.
 Access the following links for each of the cities and record the high
temperature for today's forecast. The first location has already been
completed.
NOTE: Since these are real time weather readings, the weather
stations for each of the locations may submit the current temperatures to the
weather web site at different times during the day, and therefore you should
only compare the high temperature readings for today's forecast.

Part 2: Analyze the Data
 Create a scatter plot of Temperature vs. Elevation using the data you
collection above. Label the horizontal, or xaxis in meters from from 0 to
7,000m and the vertical, or yaxis in ºC from 15ºC to 35ºC.
 Add a linear trend line (line of best fit) through the data in the
scatter plot. If you are using a spreadsheet program, this can be done
automatically.
NOTE: A trend line will not cross every point but rather there should
be approximately the same number of points below the line as above it.
 Look the trend line. Estimate the approximate change in temperature for
every increase of 1,000m in elevation.
 If you used a spreadsheet, determine the following:
 Correlation coefficient
 Linear regression equation
 Based on the graph you created above and assuming all other weather
factors remained constant (same latitude, etc.), predict the
temperature for the following elevations:
 0 m
 1000 m
 2000 m
 3000 m
 4000 m
 Highest Elevation: Mt. Everest, located on the border of Nepal and Tibet,
is the world's tallest mountain with an elevation of 8848m.:
 Assuming no other factors affected the temperature, what would be your
prediction for the temperature at the summit?
 The
actual temperature on the summit of Mt. Everest varies from 15 ºC to as low as 36
ºC. What might account for the differences between your prediction and the
actual temperatures? (Hint: Locate Mt. Everest on a world map)
 Lowest Elevation (not under seawater):
The Bentley Subglacial Trench
located in Antarctica has the world's lowest elevation not under seawater at
2555m (although the trench is covered by approximately 3000m of snow and ice).
 Assuming no other factors affected the temperature, what would be your
prediction for the temperature?
 The actual temperature of the trench is significantly below 0 ºC. What
might account for the differences between your prediction and the actual
temperatures? (Hint: locate Antarctica on a world map)

Part 3: Final Conclusions
 How does elevation affect temperature?
 Can you rely on one day's worth of data to determine a general trend
between temperature and elevation? Explain.
 If you would opt to collect more data, how much do you think would be
sufficient?
 How could you obtain this data?
 In the troposphere, the lowest, or innermost layer of earth's atmosphere,
both air pressure and the density of air (the number of gas molecules per
cubic measurement) decrease as elevation increases. How and why do you think
this affects the change in air temperature as elevation increases?

Homework
How do your conclusions compare with your hypothesis that you wrote in
your How and Why statements from Activity C1: Factors that influence Temperature? 




