Latitude and Longitude

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Name: _____________________________ Date: ___________
Period: __________
Where in the World is Boonville, New York?
Background Information
Virtually all maps have lines of latitude (called parallels) and longitude (called meridians)
expressed on them. Together, these sets of lines create an imaginary grid that can be used
to locate any point on Earth.
The latitudes lines, or parallels, run around a globe from east
to west and are measured in degrees. Each degree is divided
into 60 parts called minutes. Each minute is divided into 60
seconds of latitude. The parallel that lies at 0º of latitude is
the Equator. The rest of the parallels run 90º north of or 90º
south of the equator. If you were to cut along the parallels of
an orange, you would be cutting disks.
For example, Boonville has a latitude of about 43º north,
which means, if you headed north from the Equator, you
would reach the same latitude as Boonville on you had come
to about the 43rd line of latitude.
The meridians of longitude run from north to south on a globe from
pole to pole. They are measured in degrees, which in turn are
divided into minutes, which in turn are divided into seconds. If you
were to cut along the meridians of an orange, you would be cutting
wedges. 0º longitude is called the Prime Meridian and is the
longitude that runs through Greenwich, England. The rest of the
meridians run 180º to the east and 180º to the west of the Prime
Meridian. The maximum longitude on Earth is 180º - the
International Date Line.
For example, Boonville has a longitude of about 75ºwest, which
means, if you headed west from Greenwich, you would reach the
same longitude as Boonville once you had come to your 75th line of
longitude.
In reality, longitude measures time - time from the Prime Meridian. Because the Earth
rotates at a rate of 15º/hour (Earth rotates once every 24 hours), every 15º of longitude
equals on hour of time. That is why there are 24 time zones on Earth. As you move to
the west, every 15º equals one hour earlier in the day. As you move to the east, every 15º
equals one hour later in the day.
Information on latitude and longitude is typically written something like this (these are
Boonville, NY coordinates): 43º 28’N, 75º 21’ W. The latitude comes first (43º 28’N),
then the longitude comes second (75º 21’ W).
Part A
Using the background information, your earth Science Reference Tables, your notes, and
any other sources, complete the following sentences. It is possible to use one word or
phrase more than once.
1. The lines running east-west represent degrees of ______________. They are
measured from the equator in a ________________ and _____________
direction. These lines are also known as ________________.
2. The lines running north-south represent degrees of _________________. They
are measured from the prime Meridian in an _______________ and
_____________ direction. These lines are also known as _______________.
3. The geographic grid used on the globe is based on the division of a circle in
_______________ degrees. Each degree is divided into ______________ equal
parts called minutes, and each minute into _____________ equal parts called
______________.
4. Latitude is numbered from ____________ degrees at the Equator to
____________ degrees at either pole.
5. Longitude is numbered from ______________ degrees at the Prime Meridian to
____________ degrees at the International Date Line.
6. Longitude measure ______________ from the Prime Meridian. Earth rotates at a
rate of ___________________, so when moving to the east, it will be
______________ in the day and moving to the west will be _____________ in
the day.
Part B
Use the grid below to answer the following questions.
1. Label the Equator and Prime Meridian.
2. What are the coordinates of point A?
3. Locate the same coordinates on a globe. In what country is point A located?
4. What are the coordinates of point B?
5. Locate the same coordinates on a globe. In what country is point B located?
6. Locate a point at 10ºS and 45º W. Label it C.
7. Locate a point at 20º N and 75º E. Label it D.
8. Mark the location of Boonville, NY on the grid and label it Boonville (see
background reading for coordinates).
9. If it is 12 noon at point A, what time is it at point B?
Part C
Determine the latitude and longitude for the following cities using your Earth Science
Reference Tables (be sure to use the correct notation - latitude first, then longitude, and
they must have a compass direction! Round all values to the nearest minute!):
Jamestown
(EXAMPLE)
Elmira
42º 8’ N, 79º 15’ W
Kingston
Old Forge
Ithaca
Massena
Mt. Marcy
Watertown
Determine which city is located at the following coordinates:
43º 24’ N, 76º 30’ W
(EXAMPLE)
42º 48’ N, 78º 48’ W
Oswego
43º 06’ N, 79º 01’ W
44º 39’ N, 73º 18’ W
1. Using a ruler, measure and record how many centimeters are between Jamestown
and Elmira.
2. Using the scale on the right hand side of the map and the value you calculated
from above, what is the real distance between the two cities?
3. What large city’s latitude is similar to that of Syracuse?
4. What is this city’s latitude and longitude?
Reading Comprehension Read the portion of the article on Latitude and Longitude
below and answer the following questions based on the reading. Use complete sentences
Latitude and Longitude
By Ted Andros
http://www.broward.org/library/bienes/lii14010.htm
Since earliest times, astronomers and mapmakers have used the equator to divide the world into northern
and southern hemispheres. The starting point for longitude, however, has varied many times over the ages.
It has been located in Egypt, Greece, Spain, France, and other places, depending on which country was
preeminent at the time in the study of location by celestial observation. In 1884, the international
community adopted Greenwich as the mean in order to standardize world mapmaking.
The use of grid lines (latitude and longitude) was first suggested by the Greek astronomer Hipparcus about
300 years before Christ. Shortly after, Hipparcus devised the method of fixing the location of places on
earth by observation of the celestial bodies--the sun, moon and stars. He worked out the mathematics of
spherical trigonometry, which allowed the results of these observations to be plotted on an earth that he
perceived to be a sphere.
Some 75 years later (around 225 B.C.) Eratosthenes, another Greek mathematician and astronomer,
measured the circumference of the earth (accurate to within 300 miles) raising the art of mapmaking to new
standards of accuracy.
From that point on, the Greeks could find latitude quite easily. They knew the position of the sun north or
south of the equator. By using spherical trigonometry they could measure the sun’s angle at noon relative to
the equator. Noon was easy to determine since it occurred when the sun was at its highest point in the
heavens.
Longitude, however, was not so easy. The distance from one place to another on the earth in an east-west
direction could be plotted from the position of the stars and sun, but only if the time difference between the
two places was known. The measurement of longitude was to remain inexact until the invention of the
telescope and the accurate clock, almost two thousand years later.
1. What was observed to create a grid line system on Earth?
2. Why was the Sun measured at noon to find the distance from the equator?
3. What does longitude measure and why is it harder to measure?
Extension Activity - Battleship: the Game!!!!
So now that you understand that every point on Earth’s surface has a specific latitude
and longitude that describes its position (each consisting of a number in degrees and
importantly a direction), there are some very practical uses for knowing where
something is on Earth’s surface. Take for example warfare; knowing where an
enemy is located is vital to win a battle and for one’s own survival. In such a
situation, knowing the latitude and longitude in degrees isn’t quite accurate enough.
One degree on Earth’s surface covers about 69 miles (111 kilometers). To be able to
pinpoint where the enemy may be, a smaller scale must be used.
It was mentioned in the introduction of this lab that every degree of latitude or
longitude can be divided into smaller parts: each degree is divided into 60 minutes (‘).
One minute covers about 1,850 meters. Knowing where an enemy is at this scale
may still not be accurate enough, so each minute of latitude and longitude can be
further divided into 60 seconds (“). One second equals approximately 30 meters plenty accurate when blowing your enemy up to smithereens (not that I’m promoting
it).
To help illustrate the point, you can play the classic game Battleship. Directions for
play are on the back of this sheet. But first, let’s take a look at the latitude/longitude
grid for the game:
• The proper format for writing latitude and longitude is as follows:
Degrees (º) Minutes (‘) Seconds (“)
• The grid covers an area approximately 360,000 square meters in area (600m x
600m)
• The latitude and longitude scales are in seconds
Using this information, and before you play the game, see if you can answer the
following questions:
1. Looking at the grid for the game, is the “battlefield” in the northern or
southern hemisphere? Explain how you can tell.
2. Looking at the grid for the game, is the “battlefield” in the eastern or western
hemisphere? Explain how you can tell.
3. Using a globe, locate the latitude and longitude of the battlefield area. What
geologic feature is this area located near?
4. Considering the location of this area, who (country) is the enemy you are
fighting?
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