Timezones CGC1D

Time Zones The Earth has 24 times zones because it takes the Earth 24 hours to revolve around its axis The Earth has 24 times zones because it takes the Earth 24 hours to revolve around its axis Most time zones are one hour apart Most time zones are one hour apart Since the Earth rotates 15 degrees of longitude per hour, the Earth’s 360 degrees were divided into 24 zones, each measuring about 15 degrees in width (360 / 24 = 15) Since the Earth rotates 15 degrees of longitude per hour, the Earth’s 360 degrees were divided into 24 zones, each measuring about 15 degrees in width (360 / 24 = 15) Every place within a time zone has the same time, referred to as its standard time Every place within a time zone has the same time, referred to as its standard time

History of Timezones Standard time zones were not required prior to the 1800s because it was impossible for people to travel large distances in a short period of time Standard time zones were not required prior to the 1800s because it was impossible for people to travel large distances in a short period of time The development of rapid railway transportation changed travel dramatically, allowing people to travel large distances quickly The development of rapid railway transportation changed travel dramatically, allowing people to travel large distances quickly

History of Timezones This caused confusion, since every town set their own clocks by the sun This caused confusion, since every town set their own clocks by the sun Ex: 8:00 in Ottawa would be about 7:45 in TorontoEx: 8:00 in Ottawa would be about 7:45 in Toronto A Canadian engineer same Sir Sandford Fleming proposed a system of standard time zones A Canadian engineer same Sir Sandford Fleming proposed a system of standard time zones

Global Time Zones The prime meridian is the centre time zone The prime meridian is the centre time zone Time in this zone is called universal time (UT) and the standard time in other zones is compared to it Time in this zone is called universal time (UT) and the standard time in other zones is compared to it Time zones west of the prime meridian are earlier than the universal time (the time at the prime meridian) Time zones west of the prime meridian are earlier than the universal time (the time at the prime meridian) E.g. if UT is 12:00am, next time zone west is 11:00pm. E.g. if UT is 12:00am, next time zone west is 11:00pm.

Global Time Zones Time zones east of the prime meridian are later than the universal time (the time at the prime meridian) Time zones east of the prime meridian are later than the universal time (the time at the prime meridian) E.g. if UT is 12:00am, next time zone east is 1:00am. E.g. if UT is 12:00am, next time zone east is 1:00am.

Canada’s Timezones Canada spans 6 time zones Canada spans 6 time zones From east to west they are: From east to west they are: Newfoundland Time Zone Atlantic Time Zone Eastern Time Zone Central Time Zone Mountain Time Zone Pacific Time Zone

Ottawa’s Timezone Ottawa is in the Eastern Standard Time Zone Ottawa is in the Eastern Standard Time Zone If it is 1:00pm in Ottawa it is the same in all of this time zoneIf it is 1:00pm in Ottawa it is the same in all of this time zone

If I could travel around the earth (to the east) in an instant I would cross 24 time zones. Each time I would cross a time zone I would move my clock up one hour. When I get back to where I started I would be one DAY ahead of everyone else!

This happened to a famous explorer by the name of Ferdinand Magellan. In order to correct this problem The International Dateline was created. It is an imaginary line that simply tells travelers to adjust their calendars. If you are traveling east and cross the dateline you go back one day. The dateline is the 180 degree line of longitude, directly opposite the Prime Meridian. The International Dateline

Monday Sunday

Daylight Savings Time Many parts of the world change their time according to the season Many parts of the world change their time according to the season During the summer, daylight saving time is used to extend daylight hours During the summer, daylight saving time is used to extend daylight hours For example the sun in standard time would set at 8:00pm but when time is in daylight savings it would set at 9:00pm (therefore 1 more hour of daylight) For example the sun in standard time would set at 8:00pm but when time is in daylight savings it would set at 9:00pm (therefore 1 more hour of daylight)

Daylight Savings Time Energy is saved and people get to enjoy more of the day Energy is saved and people get to enjoy more of the day i.e. wake up when light, go to bed when darki.e. wake up when light, go to bed when dark In Canada time is changed to daylight saving on the second Sunday in March and ends the first Sunday of November In Canada time is changed to daylight saving on the second Sunday in March and ends the first Sunday of November “Spring ahead, fall back” “Spring ahead, fall back”

Observe Daylight Savings TimeTried it but gave it up Never used it

What’s up with Saskatchewan? Saskatchewan is naturally located within the Mountain Standard Time (MST) – the same timezone as Alberta. Saskatchewan is naturally located within the Mountain Standard Time (MST) – the same timezone as Alberta. Under The Time Act of 1966, Saskatchewan adopted Central Standard Time, so shares the same timezone as Manitoba Under The Time Act of 1966, Saskatchewan adopted Central Standard Time, so shares the same timezone as Manitoba But since they don’t observe Daylight Savings time, they share the same time as Alberta during the summer months and the same time as Manitoba during the winter months But since they don’t observe Daylight Savings time, they share the same time as Alberta during the summer months and the same time as Manitoba during the winter months