World map of the difference between solar and clock time | Hacker News Reader

World map of the difference between solar and clock time

blog.poormansmath.net

219 pointsgmac39 comments

This is so cool! But the coloring is a bit frustrating because -1 on the scale is just as red as -2 or -3 or more.

So, for example, Western China is the region that is most disconnected from solar time. It's off by more than 3 hours. (Imagine a summer sunset at midnight, or a winter sunrise at 10am.) But it looks just as red as Saskatchewan, which is off by only an hour.

Note that while China has one official time zone, in practice many people (particularly Uighurs in the west) use local time zones with less error.

Loosely related: a study looking at how sleep patterns impact productivity, as measured by looking at wages on eastern and western edges of time zones. http://econweb.ucsd.edu/~magibson/pdfs/sleep_productivity.pd...

A glorious find, if my tired mind groks the summary (it's a long article). Objectively confirms the adage "early to bed, early to rise, makes a man healthy wealthy and wise", no? and establishes another strong argument against Daylight Saving Time? 12:40am, time for bed.

Bill Nye had a clock built at Cornell University to emphasize this difference: http://www.news.cornell.edu/stories/2011/08/bill-nye-77-harn...

That shows the difference between standard time and local apparent solar time. Apparent solar time varies through the year according to the equation of time.

This map shows the difference between standard time and local mean solar time, which is fixed. There is a clock on the Corn Exchange in Bristol with two minute hands with a fixed angle showing the difference between Bristol and Greenwich mean time. The clock dates from the period when Railway Time (GMT) was the practical time in common use, but British legal time was local mean time.

https://en.wikipedia.org/wiki/The_Exchange,_Bristol#Clock

London sitting pretty at (of course) +0 GMT and right on Solar time as well.

That's not a big deal but it points to seemingly eternal benefits of being the world's leading power for a time. Americans overlook many of those benefits, I think.

For example, because the Internet and much of personal computing originally were developed in the U.S., the whole world accomodates English and the ASCII character set. If that doesn't seem like a big deal, then imagine if you had to adjust to German, Arabic, or Japanese.

And there is the the UK cashing in on their former dominance again: Because their empire included N. America, the world operates on their language (and a very similar culture).

Or just go to China and see so many people dressing like Westerners, using western techology, etc. Much of what we assume as 'modern' society is western; just think of automobiles and their basic design, for example, or the telephone, TV, etc. Imagine how it feels to see that all your tech was developed elsewhere (which is an unfortunate accident of history and a situation that probably won't last much longer).

Yeah, but despite all that we're still called 'Westerners'. The victory is not yet complete.

If England hadn't kicked off the industrial revolution it might have taken another few centuries to start and you'd be shitting in a hole in the ground in the dark right now. So be grateful for the huge gift they gave all of us.

Does anyone here live somewhere with a large difference? In particular Chile and Argentina look like solar noon is a couple of hours after clock noon. Sounds like the kind of place for late sleepers.

The fact that most of Europe is in the same timezone is disturbing. I remember visiting Budapest (East of the timezone), coming from Bordeaux (West of the timezone), and noticing how much earlier (1h30) dusk was.

I wonder if it has an impact on the mood of the inhabitants.

I'm pretty sure it has. I always feel jet-lagged in Paris, in a way I never felt in London or Berlin (both closer to their solar noon). Also felt deeply unwell in Bilbao (although the city's so brilliant). The most noticeable thing is that 7am is night time about half the year in Paris (from October to April) when it's at least dusk in London all year long (maybe not in December).

It's pretty clear that Paris is less of a morning-city than London.

Having lived in all 3 countries, I can tell you that Austrians (roughly centred on solar time, and Vienna, 1/4 of the country's population in one city, almost half an hour ahead of solar) are very much early risers compared to Spaniards. (the eastern part of Spain is almost 1 hour behind solar, most of the country even more so) Opening times of shops reflect that; it's not unusual for supermarkets in Spain to open at 9:00, while in Austria 7:30 is probably the most common. The evening meal is generally also consumed much later (clock time) in Spain. The UK is somewhere in between, which again fits with the solar time offset.

Drawing any conclusions beyond that is frought with the peril of confounding factors…

Indeed: I once walked into a restaurant in Spain and was told they were not yet open for dinner. The time was 8 pm.

There's a story about Spain.

Spain used to be in the same timezone as the UK. It made sense, as the Greenwich Meridian crosses the east of the Iberian Peninsula. But in 1942, the fascist dictator Franco decided to use the same timezone as the Nazi Germany and adopted the continental timezone (GMT+1).

The fun part of the story is that, as the Sun didn't actually move, the people kept doing their life at the same moments as before. That's why nowadays in Spain is usual to have lunch at 14 and dinner at 22. Specially in the West.

In China we have a single, big, timezone. It's a bless, there's no need to convert time when you are travelling. I live at northwest China, has more than two hours difference from Beijing. You only need to delay your living pattern by 2 hours, so no bonus for late sleepers.

> It's a bless, there's no need to convert time when you are travelling.

Hah, and people here are all for having timezones. "Imagine how crazy it would be to have the sun coming up at 3AM in some places and 7PM in others!" I can't be sure without trying, but I'd argue it's pretty much equally messed up with and without timezones. Right now as a computer guy, I know time zones make everything more complicated.

When traveling somewhere for business you make an appointment anyway, so you know when you have to be somewhere and can plan accordingly. For holidays you'd look up the local sunrise time (which varies pretty much everywhere on earth anyway, albeit a bit more predictably now).

It's really comfortable. In Argentinean winter, as you wake up at 9am the light day begins, and you've got a long evening still where restaurants do not open before 9pm.

In Chile:

On weekends, the time to go out for a drink (Chilean people call it "salir de carrete") starts no earlier than midnight, though somewhat earlier during the week. The pubs and clubs close at 5 AM on weekends, and 4 AM on weekdays.

(c)ourtesy wikitravel

This is the main reason why I think eliminating leap seconds won't be harmful. Very few people have "correct" solar time today anyway.

Leap seconds aren't about people but about highly accurate machines and keeping highly exact measures of time, whatever "time" means.

Irregularly jumping backwards 1 second is really helpful for that...

Physics still wins whether it's helpful or not.

If it were just about keeping exact measurements of time, there would be no need to regularly resynchronize the standard timekeeping system with the rotation of the Earth. The only thing that makes it important to tie clock noon to solar noon (which is the entire purpose of leap seconds) is to maintain human beings' perception of what "noon" is supposed to mean (over the very long term).

There's a related Freakonomics episode talking about timezones and productivity: http://freakonomics.com/2015/07/16/the-economics-of-sleep-pa...

Apparently, time in Spain got shifted in WW2 and never came back: https://en.wikipedia.org/wiki/Time_in_Spain#Central_European...

Same in the Netherlands.

Cool map! I suppose that for daylight savings time everything would get one hour more red.

Why do all the islands is the Atlantic skew left of the time zone they should be in?

To be closer to their mainland or neighbour's timezone.

This came up last year when I was talking with a friend in Boston. Even though we're in the same timezone, their sunset is over half an hour earlier than ours. Interesting to think about.

Shouldn't those vertical line-patterns be slanted? I mean, the axis of the Earth is not perpendicular to the plane in which it rotates around the Sun.

The angle of the Earth causes the sun to peak at a lower altitude, it doesn't cause it to peak at a different time.

Is this true in all seasons?

Yep. The days are shorter (that is, fewer hours of light) in winter seasons because the sun is at a lower angle and spends more time below the horizon, not because there are fewer hours in the day. Your noon will repeat regularly every 24 hours no matter what season it is.

Just more fuel for helping California residents feel smug

:-)

Perhaps one of the many reasons my life just makes more sense in California (in spite of the high cost of living and other issues).

:-)

What always bothers me in maps like these is how ridiculously detailed the shorelines are. Who cares that you can see individual islands off the southern coast of Chile?

You work with the vector map of the world that you got.

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