1. Map Reading and Interpretation
Latitude and Longitude

2. Purpose Locational reference system
The grid system (meridians and parallels) that surrounds the earth is used for locating places
Each grid line is identified with a number
The intersection between the meridian number and the parallel number identifies a place’s location
There is an infinite number of parallels and meridians
Parallels and meridians always intersect at right angles

3. Latitude / Longitude

4. Parallels / Latitude Parallels = Latitude Remember:
Imaginary lines that run east and west on a map. Parallels represent degrees of latitude, or how far a place is away from the equator.
Equator = 0o latitude
North pole = 90o north latitude
South pole = 90o south latitude
Remember:
Minimum latitude is 0o
Maximum latitude is 90o

5. Parallels / Latitude
Latitude of a location is the particular distance (north or south) of the location from the equator
Measurements
At the equator
the length of 1o latitude means km
At the poles
The length of 1o latitude means km
For simplicity:
The length of 1o latitude will equal 111 km

6. Latitude

7. Meridians / Longitude Meridians = Longitude Remember:
Imaginary lines that run north and south on a map from pole to pole. Meridians express degrees of longitude, or how far a place is away from the prime meridian.
Prime Meridian = 0o longitude
Runs through Greenwich, England
International Date Line = 180o longitude
Remember:
Minimum longitude is 0o
Maximum longitude is 180o

8. Meridians / Longitude
Longitude of a location is the particular distance (east or west) of the location from the prime meridian
Measurements
At the equator
the length of 1o longitude is approximately 111 km
At 60 north and south of the equator
The length of 1o longitude is 55.5 km

9. Longitude

10. Reading Latitude / Longitude
Writing coordinates
Intersecting Coordinates / Unique point where lines cross:
Latitude always comes before longitude
Add the direction
Example:
Latitude / Longitude coordinates: 30oN30oE
Points between degrees
Degrees are subdivided into minutes
60 minutes in each degree / 60 seconds per minute
Example: 20o30’30”N 35o30’30”W

11. 60oN
30oE

12. Practice

13. Answers to Practice Map Sheet 3: Activity 1
A 20oS 100oE
B 80oN 0o
C 0o 140oW
D 60oS 40o W
E 40oN 60oE
F 20oS 20oE
G 40oN 100oW
H 20oN 40oE
I 50oN 120oE
J 10oS 40oW

14. Use a world map to find latitude and longitude of the following cities to nearest full degree. Then in brackets put the minutes.
Washington
London
Moscow
Tokyo
Vancouver
Ottawa

15. Answers to Sheet 3: Activity 2
Use a world map to find latitude and longitude of the following cities to nearest full degree.
(Brackets represent degrees and minutes)
Washington - 39°N 77°W (38°55'N 77°00'W)
London - 52°N 0° (51°30'N 0°10'W)
Moscow - 56°N 38°E (55°45'N 37°42'E)
Tokyo - 36°N 140°E (35°40'N 139°45'E)
Vancouver - 49°N 123°W (49°13'N 123°06'W)
Ottawa - 45°N 76°W (45°24'N 75°38'W)

16. Precision with Latitude / Longitude
Reading Latitude / Longitude
30o 15’ 9”
It may also show N
Seconds
Degrees
Minutes

17. Expressing Degree Degrees may be expressed as: Coordinate: 65o 32’ 15”
Decimal:
Degrees and decimal minutes: 65o 32.25’
Degrees, minutes and decimal seconds: 65o 32’ ”
32/60 = .53 and 15/3600 = For just take the 15 seconds and / by 60

18. Conversion Degrees:Minutes:Second to Degrees 65o45’36” S (S65:45:36)
+ (45 min x 1 degree/60 min)
+ (36 sec x 1 degree/60 sec x 1 degree / 60 min)
= South latitude
45 / 60 = .75 and 36 / 3600 = .01 So = .76 That’s how to get the decimal

19. Reading Topographic Maps
A more precise location can be identified using your knowledge of latitude and longitude measurements of degrees, minutes and seconds

21. Topographic Point Locations
Point A: 40o 30’ N 118oW
Point B: 40o 25’ N 117o 55W
Point C: 40o 20’ N 117o 50’W
Point D: 40o 27’ 30” N 117o 47’ 30” W
Point E: 40o 16’ N 117o 52’ 30”W

22. Activity: Sheet 3B
On the topographic map provided, estimate the coordinates of the following locations (use the first letter of the name).
Use the greatest precision possible.

23. Answers: Sheet 3B Brewer Mills 46o 04’ 30”N 66o 59’ 59”W
Morehouse Corner 46o 04’ 10”N 66o 58’ 30”W
Zealand 46o 03’ 10”N 66o 56’ 15”W
Keswick Ridge 46o 01’ 15”N 66o 54’ 45”W
MacLean Settlement 46o 04’ 20”N 66o 50’ 50”W
Lower Stone Ridge 46o 04’ 10”N 66o 54’ 55”W
Pughs Crossing 46o 03’ 10”N 66o 51’ 00”W
Sisson Settlement 46o 02’ 40”N 66o 51’ 50”W
Tripp Settlement 46o 01’ 10”N 66o 54’ 05”W
Keswick 46o 00’ 10”N 66o 49’ 40”W

24. Riddle
An explorer walked one mile south, one mile east, one mile north and came back to the original point. Where did this happen?
North Pole