Time Zones Lesson

Socials 8Mr. Goldsack

In this Lesson…• 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

Time zones run along lines of

longitude, so each place along that line will be in the same time zone.

Greenwich Mean Time

Each time zone = 15° wide

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•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.

lick ccrc cor morc incoc

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• You can tell what

time it is in your area by knowing:

a) Greenwich Mean Time

b) Your longitudeEg./

• What is your time if you’re 105°E of the Prime Meridian and GMT is 4:00 pm?

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?

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.

sextantastrolabe

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°.

compass

sundial

chronometer

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• Anchors Aweigh! Game• Daylight Saving Time website• Watch the GMT Clock Ticking• Time in Other Cities Around the World