Time Zones Lesson
Socials 8
Mr. Goldsack
In this Lesson…
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You will learn the origins of time zones.
You will understand how time zones work
You will learn about Canada’s time zones.
You will know the purpose of daylight
savings time.
• You will be able to explain the tools
explorers used to determine location.
Imagine a World Without Time Zones!
It would be
quite chaotic!
What are
some
problems that
would occur?
Time Zones Background
• The world is divided
into 24 time zones.
• The world turns 360°
in one day, so each
time zone is 15° wide
(360/24)
• The International Date
Line (IDL) at 180° is
the designated line for
date change.
• If it’s Sunday in Alaska,
it’s Monday in Siberia.
World Time Zone Map
Each time zone = 15°
wide
Time zones run along
lines of longitude, so
each place along that
line will be in the same
time zone.
Greenwich Mean Time
Sir Stanford Fleming
•Chief surveyor for the
Canadian Pacific
Railway…a Canadian!
•Needed standard times
for trains to run on
schedule.
•Idea for 24-one-hour
time zones was accepted
at the International Prime
Meridian Conference in
1884.
•This is the global
standard we use today.
I invented
time zones
for railway
time
schedules.
Canadian Time Zones
Click here for more info.
•Canada has 6 time
zones.
•BC is located in
Pacific Mountain Time
•Toronto is 3 hours
ahead of us.
•Creston is one hour
ahead of us only in the
spring during Daylight
Saving Time.
•Nfld has it’s own 1/2
hour time zone.
Canada Time Zone Map
Click on icon
for activity.
Daylight Saving Time
•DST was proposed by an
American named Benjamin
Franklin.
•He thought it would save
energy costs during the
day.
•It would also extend the
summer days by an hour so
people could enjoy staying
out.
•“Spring forward, fall back”
1st Sunday in April, last
Sunday in October.
Click here for more info
Greenwich Mean Time
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Answer: 105 divided
by 15=7.
If it’s 4 pm GMT,
then add 7 hours.
So, it’s 11 pm where
you are. In which
continent are you?
You can tell what
time it is in your
area by knowing:
a) Greenwich Mean
Time
b) Your longitude
Eg./
• What is your time if
you’re 105°E of the
Prime Meridian and
GMT is 4:00 pm?
How Explorers Navigated
•Early explorers used
latitude to chart their
course.
•They used a sextant to
determine latitude by
measuring the angle of
the North Star from the
equator.
•In the South, they
used the Southern
Cross star in a similar
way.
 Click here for more info.
astrolabe
sextant
How Explorers Found Longitude
•They would need a
chronometer that told
the GMT (Greenwich
Mean Time).
•They would use a
sundial to tell them the
ship’s time.
•They would calculate
their longitude based
on the difference
between GMT and their
time x 15°.
sundial
chronometer
compass
Navigating With Giovanni
According to our sextant, we are sailing at
20°N. If it is 10 am according to our
sundial, and GMT is 4 pm, where are we?
Answer: There is six hours earlier
difference. Multiply 6 x 15° = 90°W.
Can you figure out where we are?
Click on icon for
answer.
Other Links of Interest to Try
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Anchors Aweigh! Game
Daylight Saving Time website
Watch the GMT Clock Ticking
Time in Other Cities Around the World