Introduction to the Geographic Grid
Created by:
Mark W. Bowen
Department of Geography and Urban Planning
University of Wisconsin Oshkosh
Oshkosh, WI 54901
Phone: 920-424-7114
E-mail: bowenm@uwosh.edu
Purpose:
The purpose of this exercise is to become familiar with the latitude-longitude geographic grid
used to describe location on the Earth’s surface.
Essential Learning Outcomes:
Determine the latitude and longitude of a location
Determine a location based on latitude and longitude
Calculate distance using latitude and longitude
Convert between decimal degrees and degrees, minutes, seconds
Equipment supplied:
Calculator
World atlas
Globe
Instructor notes:
For this exercise I ask students to get into pairs to complete the assignment. Lab enrollment is
typically 32 students per section, requiring 16 globes and 16 atlases. You could easily have
students work independently if you have enough resources or in larger groups if you are limited
by the number of globes and atlases. If you prohibit the use of cell phones or other technology in
class, you will want to also supply calculators – very basic ones will suffice.
Depending on the publisher and edition of the atlas and globe, some of the cities or locations
included in this exercise may not be included on atlas maps or on the globe.
Also note that the questions ask for answers in degrees, minutes, seconds. I usually spend a few
minutes explaining this. Keep in mind that the index in the back of the atlas typically does not
include seconds, so their answers will be in degrees, minutes
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Exercises:
Part 1 – Latitude and Longitude
Use a globe and atlas to answer the following:
1. What are the location, latitude, and longitude of the southernmost point in the conterminous
United States? Report your answer in degrees, minutes, seconds and in decimal degrees.
(Tip: There are 60 seconds in 1 minute, and 60 minutes in 1 degree.)
Key West, Florida, 24° 31’ N, 81° 47’ W (24.52° N, 81.78° W)
2. What are the location, latitude, and longitude of the southernmost point in all of the United
States? Report your answer in degrees, minutes, seconds and in decimal degrees.
Ka Lae / South Point, Hawai’i, 18.91° N, 155.68° W
3. Which is at higher latitude, the border between the state of Washington and Canada or the
border between Maine and Canada? What is the approximate latitude of each?
Washington - ~49° N; Maine - ~47.5° N
4. What are the location, latitude, and longitude of the northernmost point in all of the United
States? Report your answer in degrees, minutes, seconds and in decimal degrees.
Barrow, Alaska at 71° 20’ N, 156° W (71.33° N, 156.00° W)
5. What are the location, latitude, and longitude of the westernmost point in the conterminous
United States? Report your answer in degrees, minutes, seconds and in decimal degrees.
Cape Alava, Washington, 48° 10’ N, 124° 44’ W (48.17° N, 124.73° W)
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6. What are the location, latitude, and longitude of the westernmost point in all of the United
States? Report your answer in degrees, minutes, seconds and in decimal degrees.
Amatignak Island, Alaska, 51° 16’ N, 179° 9’ W (51.26° N, 179.15) – this is a bit of a
trick question as there are islands further west, but they are then in the eastern
hemisphere
7. What are the location, latitude, and longitude of the easternmost point in the conterminous
United States? Report your answer in degrees, minutes, seconds and in decimal degrees.
West Quoddy Head, Maine, 44° 49’ N, 66° 57’ W (44.82° N, 66.95° W)
8. Which ten countries does the equator pass through?
Gabon, Republic of the Congo, Democratic Republic of the Congo, Uganda, Kenya,
Somalia, Indonesia, Ecuador, Colombia, and Brazil
9. Which eight countries does the Prime Meridian pass through?
England, France, Spain, Algeria, Mali, Burkina Faso, Ghana, Togo
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10. Using a globe, locate three cities near the Tropic of Cancer. Determine the approximate
longitude of each city.
City and Country
Longitude
a.
Mazatlan, Mexico
106° 27’ W
b.
Havana, Cuba
82° 23’ W
c.
Muscat, Oman
58.5° W
There are several other potential correct answers as well.
11. Using a globe, locate three cities near the 30th E meridian. Determine the approximate
latitude of each city.
City and Country
Latitude
a.
St. Petersburg, Russia
60° N
b.
Alexandria, Egypt
31° N
c.
Kigali, Rwanda
2° S
12. Using a globe, locate three cities in three different countries at similar latitude as your
campus. Determine the approximate longitude of each city.
City and Country
Longitude
a.
b.
c.
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13. Using a globe, locate three cities in three different countries at similar longitude as your
campus. Determine the approximate latitude of each city.
City and Country
Latitude
a.
b.
c.
14. Using an atlas, locate three cities in three different states in the U.S. at similar latitude as
your campus. Determine the approximate longitude of each city.
City and State
Longitude
a.
b.
c.
15. Using an atlas, locate three cities in three different states in the U.S. at similar longitude as
your campus. Determine the approximate latitude of each city.
City and State
Latitude
a.
b.
c.
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16. Determine the following location of these major world cities based on the approximate
latitude and longitude:
Latitude and Longitude
Location
a. 42° N, 87.5° W
Chicago, Illinois
b. 40.4° N, 3.5° W
Madrid, Spain
c. 30° N, 31° E
Cairo, Egypt
d. 23° S, 43° W
Rio de Janeiro, Brazil
e. 34° S, 151° E
Sydney, Australia
f. 14.5° N, 121° E
Manila, Philippines
g. 33° N, 44.5° E
Baghdad, Iraq
h. 34° S, 18.5° E
Cape Town, South Africa
i. 12° S, 77° W
Lima, Peru
j. 60° N, 10.5° E
Oslo, Norway
Part 2 – Calculating distance using longitude and latitude
Lines of latitude are parallels so distance between any two lines is nearly constant at ~69
miles/degree. There are slight variations due to the Earth being oblige (i.e., not a perfect sphere),
so distance ranges from 68.71 miles/degree at the equator to 69.41 miles/degree at the poles.
Lines of longitude converge at the poles, so distance between lines of longitude vary with
latitude and ranges from 69.17 miles/degree at the equator to 0 miles/degree at the poles.
Table 1. Linear distances represented by one degree latitude and longitude
1 Degree Latitude 1 Degree Longitude
Latitude
Length (miles)
Length (miles)
90° (poles)
69.41
0
60°
69.23
34.67
45°
69.06
48.81
30°
68.89
59.96
0° (equator)
68.71
69.17
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Use Table 1 to answer the following:
17. From your campus, if you traveled west one degree and then north 1 degree, approximately
how many miles have you travelled?
This answer depends upon the latitude that your campus is located at.
18. What is the approximate distance in miles between your campus and the equator?
This answer depends upon the latitude that your campus is located at.
19. What is the approximate distance in miles between your answer to 14B and the equator?
This answer depends upon the latitude that your campus is located at.
20. What is the approximate distance between your campus and the Prime Meridian?
This answer depends upon the latitude and longitude that your campus is located at.
21. What is the approximate distance between your answer to 15B and the Prime Meridian?
This answer depends upon the latitude and longitude that your campus is located at.
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