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Let’s talk about the GLOBE!

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Why do we even have time zones?

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Compiled by @zbpipe to share

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All time zones are measured from a starting point centered where?

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This Photo by Unknown Author is licensed under CC BY-SA

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All time zones are measured from a starting point centered at England's Greenwich Observatory.

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This point is known as the Greenwich Meridian or the Prime Meridian. Time at the Greenwich Meridian is known as Greenwich Mean Time (GMT) or Universal Time.

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The Eastern time zone in the United States is designated as GMT minus five hours. When it is noon in the Eastern time zone, it is 5 p.m. at the Greenwich Observatory.

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The International Date Line (IDL) is located on the opposite side of the planet from the Greenwich Observatory.

This Photo by Unknown Author is licensed under CC BY-SA

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It’s a matter of geography. The further you travel from the Equator, the more drastic the seasons will be. That’s because Earth is tilted on its axis with respect to the sun, so the top and bottom portions of the globe receive more or less sunlight at different times of the year, making the loss of daylight hours more pronounced.

This Photo by Unknown Author is licensed under CC BY-SA

Each planet in our solar system rotates on its axis. So, each planet has a North and South Pole, the points where an axis meets the planet's surface

The time it takes for a planet or other celestial object to complete one spin around its axis is called its rotation period. Earth's rotation period is about 24 hours, or one day

Earth's axial tilt (also known as the obliquity of the ecliptic) is about 23.5 degrees. Due to this axial tilt, the sun shines on different latitudes at different angles throughout the year. This causes the seasons.

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All time zones are measured from a starting point centered at England's Greenwich Observatory.

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This point is known as the Greenwich Meridian or the Prime Meridian. Time at the Greenwich Meridian is known as Greenwich Mean Time (GMT) or Universal Time.

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The Eastern time zone in the United States is designated as GMT minus five hours. When it is noon in the Eastern time zone, it is 5 p.m. at the Greenwich Observatory. The International Date Line (IDL) is located on the opposite side of the planet from the Greenwich Observatory.

This Photo by Unknown Author is licensed under CC BY-SA

This Photo by Unknown Author is licensed under CC BY-NC-ND

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To understand time zones, start by thinking about the shape of the Earth.

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You know our planet is a sphere that spins on an imaginary pole called its axis.

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Every 24 hours, the Earth makes a complete rotation.

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We call each full turn a day.

This Photo by Unknown Author is licensed under CC BY-SA

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Having multiple time zones is to divide the world into 24 15-degree slices and set the clocks accordingly in each zone.

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All of the people in a given zone set their clocks the same way, and each zone is one hour different from the next.

This Photo by Unknown Author is licensed under CC BY-SA

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Imagine shining a flashlight

at a globe.

Only part of it would receive light. The opposite side would be dark.

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As Earth rotates, different parts of Earth receive sunlight or darkness, giving us day and night.

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As your location on Earth rotates into sunlight, you see the sun rise.

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When your location rotates out of sunlight, you see the sun set.

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Thinking Question:

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What is the connection between Time Zones and

the Economy?

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What is an entomologist?

This Photo by Unknown Author is licensed under CC BY-SA

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In 1895, George Hudson, an entomologist from New Zealand, came up with the modern concept of daylight saving time.

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Why an entomologist? 

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In 1895, George Hudson, an entomologist from New Zealand, came up with the modern concept of daylight saving time.

He proposed a two-hour time shift so he’d have more after-work hours of sunshine to go bug hunting in the summer.

Why an entomologist? 

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FACT!

1908

First Used in Canada in 1908

1916

While Germany and Austria were the first countries to use DST in 1916, it is a little-known fact that a few hundred Canadians beat the German Empire by eight years.

today's

On July 1, 1908, the residents of Port Arthur, Ontario, today's Thunder Bay, turned their clocks forward by one hour to start the world's first DST period.

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  • Seven years later, British builder William Willett (the great-great grandfather of Coldplay frontman Chris Martin) independently hit on the idea while out horseback riding.

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  • He proposed it to England’s Parliament as a way to prevent the nation from wasting daylight.

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  • His idea was championed by Winston Churchill and Sir Arthur Conan Doyle—but was initially rejected by the British government. Willett kept arguing for the concept up until his death in 1915.

This Photo by Unknown Author is licensed under CC BY-SA-NC

Source: https://www.nationalgeographic.com/science/article/daylight-savings-time-arizona-florida-spring-forward-science

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How does the Economy fit in?

In 1916, two years into World War I, the German government started brainstorming ways to save energy.

“They remembered Willett’s idea of moving the clock forward and thus having more daylight during working hours,” explains David Prerau, author of Seize the Daylight: The Curious and Contentious Story of Daylight Saving Time. “While the British were talking about it year after year, the Germans decided to do it more or less by fiat.”

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  • Soon, England and almost every other country that fought in World War I followed suit. So did the United States: On March 9, 1918, Congress enacted its first daylight saving law—and it was a two-fer: In addition to saving daylight, the Standard Time Act defined time zones in the U.S.
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  • In those days, coal power was king, so people really did save energy (and thus contribute to the war effort) by changing their clocks.

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Should we stop Daylight Savings Time?

“B.C. premier hopes Sunday’s Daylight Saving Time clock change will be the last

https://globalnews.ca/news/7693737/daylight-saving-time-2021/ …. The B.C. legislature passed legislation in 2019 giving the province the power to stop seasonal time changes — but the process has been delayed by a failure by U.S. states in the same time zone to follow suit.

Alberta government 'may be holding a referendum' on daylight saving time: https://edmonton.ctvnews.ca/alberta-government-may-be-holding-a-referendum-on-daylight-saving-time-kenney-1.5345322

Last November, the Ontario government also passed legislation that could end the clock-change and make daylight saving time permanent in that province. 

Not unlike B.C., that move would only happen if neighbouring jurisdictions—Quebec and New York—also hopped on board with the idea.

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Controversial

Today, the idea of springing forward and falling back is a bit more controversial, in part because it no longer really saves energy. But when you hear from a time-change skeptic, consider the source and where they live. If they’re from a more northerly place, they may be inclined to like saving daylight more.

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Petition: https://www.change.org/p/doug-ford-stop-observing-daylight-savings-time-or-standard-time-in-ontario

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Source: https://kids.nationalgeographic.com/science/article/daylight-saving-time

This Photo by Unknown Author is licensed under CC BY-SA

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Imagine if the entire Earth had a single time zone.

What would this be like from country to country?

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Noon would be the middle of the day in some places, but it would be morning, evening, and the middle of the night in others. Since different parts of Earth enter and exit daylight at different times, we need different time zones.

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This Photo by Unknown Author is licensed under CC BY-NC-ND

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Imagine if the entire Earth had a single time zone.

What would this be like from country to country?

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This Photo by Unknown Author is licensed under CC BY-NC-ND

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What would happen if we abolished time zones altogether?

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  • Although modern DST has only been used for about 100 years, ancient civilizations are known to have engaged in comparable practices thousands of years ago.

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  • For example, the Roman water clocks used different scales for different months of the year to adjust the daily schedules to the solar time.

An Ancient Idea

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Are time zones still needed in an ultra-connected world?

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Fast-forward to now: are time zones still needed in an ultra-connected world?

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Economist Steve Hanke and astronomer Dick Henry have been very vocal in proposing an end to time zones - something they would replace with a system aptly named the Hanke-Henry Date and Time. After all, they argue, from a physics standpoint, it's always the same time everywhere in the world.

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Why Economist and Astronomer? What common interest might they have?

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In the plan put forward by Hanke and Henry, 9am would be 9am across the world. However, some people would know 9am as bedtime, while others would see it as the start of the working day.

For example, if you were making a conference call to the other side of the planet, you'd have to work out what people usually do at 9am in their part of the world, rather than make any hourly calculations. It would be called Universal Time.

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Source: https://www.sciencealert.com/what-would-happen-if-we-abolished-time-zones

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Fast-forward to now: are time zones still needed in an ultra-connected world?

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Economist Steve Hanke and astronomer Dick Henry have been very vocal in proposing an end to time zones - something they would replace with a system aptly named the Hanke-Henry Date and Time. After all, they argue, from a physics standpoint, it's always the same time everywhere in the world.

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Why Economist and Astronomer? What common interest might they have?

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Hanke-Henry Date and Time would make life easier for businesses, countries, and airlines, say its inventors. The calendar would be identical every year, except for a one week-long 'mini-month' at the end of December every five or six years - this would bring the calendar back into sync with seasonal changes.

Your birthday is always on the same day, and Christmas Day is always on a Monday. What's more, Daylight Saving Time disappears completely. 

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Source: https://www.sciencealert.com/what-would-happen-if-we-abolished-time-zones

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Define “egregious”

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Time zone quirks exist the world over.

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To pull up some particularly egregious examples:

  • Russia has 11, while China has only one;
  • Nepal is the only place in the world where the time is (inexplicably) set to quarter past the hour
  • Two in Australia are set to the half hour;
  • Spain abides by Central European Time (CET) despite being geographically in line with the UK, meaning its citizens suffer a form of constant social jetlag –

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The Politics of it!

  • Time zones have been leveraged as a political tool throughout history

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Not that long ago…

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  • In 2015, North Korea decided to wind its clocks back half an hour, instigating Pyongyang time “to emphasize its political independence and celebrate the 70th anniversary of Korea's liberation from Japanese colonialism,” according to Jonathan Hassid, assistant professor in Political Science at the State University of Iowa.

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  • However, in 2018, after the country's relations with South Korea warmed, the clocks were again set to align with their southern neighbour. Venezuela also changed its time zone under the government of Hugo Chavez, again to signify political self-determination, and to avoid sharing a time zone with its arch enemy, America.

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Source: https://www.wired.co.uk/article/universal-time-zones

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Uranus has the largest axial tilt in the solar system. Its axis is tilted about 98 degrees, so its north pole is nearly on its equator. 

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Astronomers suspect that this extreme tilt was caused by a collision with an Earth-sized planet billions of years ago, soon after Uranus formed.

Interesting fact:

This Photo by Unknown Author is licensed under CC BY-NC

This Photo by Unknown Author is licensed under CC BY-SA

This Photo by Unknown Author is licensed under CC BY-SA

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  • In the middle portions of the planet, the amount of sun is about the same all year ‘round. As a result, the seasons are milder and there’s less of a need to make adjustments to maximize daylight.

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  • Just look at a map of the countries that use daylight saving time today to see which regions really find the shift worthwhile.

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Daylight Savings Time

In Canada, Time Zones and Daylight Saving Time usually have been regulated by provincial and territorial governments.

This Photo by Unknown Author is licensed under CC BY-NC

This Photo by Unknown Author is licensed under CC BY-SA-NC

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Newfoundland

Prior to November 2011, Newfoundland changed time at 00:01 local time.

This Photo by Unknown Author is licensed under CC BY-SA

This Photo by Unknown Author is licensed under CC BY-SA

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Quebec

The areas of Québec, east of 63° west longitude, do not change to daylight time and remain on Atlantic Standard time all year round.

This Photo by Unknown Author is licensed under CC BY-SA

This Photo by Unknown Author is licensed under CC BY

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Ontario

The areas of Ontario, west of 90° west longitude, are in the Central Time zone and change at 2:00 a.m. local time.

This Photo by Unknown Author is licensed under CC BY-SA

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Saskatchewan

Most of Saskatchewan uses Central Standard time all year round. Areas around Lloydminster are in the Mountain Time zone and change at 2:00 a.m. local time, as in Alberta.

This Photo by Unknown Author is licensed under CC BY-SA

This Photo by Unknown Author is licensed under CC BY-SA

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Nunavut

Nunavut covers 3 time zones and all zones change at 02:00 local time. Southampton Island remains on Eastern Standard time all year long.

This Photo by Unknown Author is licensed under CC BY-SA

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Yukon

Since 2020 Yukon uses UTC-7h or Yukon Standard Time all year round.

Source: https://nrc.canada.ca/en/certifications-evaluations-standards/canadas-official-time/time-zones-daylight-saving-time

This Photo by Unknown Author is licensed under CC BY-SA

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Time Zone Name Changes�

  • During DST, the local time zone name and abbreviation changes, usually to include either “daylight” or “summer” in the time zone name.
  • For example, New York's standard time is Eastern Standard Time (EST), which is 5 hours behind UTC (UTC–5). However, during DST, the city is on Eastern Daylight Time (EDT), which is 4 hours behind UTC (UTC–4).
  • In day-to-day speak, however, the time zone is often referred to as just Eastern Time, regardless of whether it's standard or Daylight Saving Time.

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Source: https://www.timeanddate.com/time/standard-time.html

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Resources

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