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Kao i svakog zadnjeg vikenda u 10. i 3. mjesecu, jučer se mediji na veliko raspisali kako “opet” pomičemo sat i kako bi pomicanje sata trebalo ukinuti i bla bla. Zanimljivo je da nikom ne smeta ljetno vrijeme do samog pomicanja sata, odnosno sve je mkay osim ona dva dana u godini kad pomičemo kazaljke.

U biti, jedan takav članak je bio na Indexu. Sad kad sam pomicao sat na blogu, padne mi na pamet da jednostavno tu stavim komentar na članak, nego da imam čitabu na Fejsu.

Inače, ovo nije jedini post u kojem sam gubio vrijeme na vrijeme 😀 Prije nekoliko godina sam napisao Time zones i Time what is time. U njima bljezgarim i o ljetnom vremenu (DST).

U biti, priča kaže sledeće:

Čudite se ko pura dreku, a većina ljudi kurca zna o ljetnom vremenu. Hrpi ljudi je pomicanje sata svake godine takav neočekivani šok iako je pomicanje sata svake godine zadnjih nekoliko desetljeća zadnje nedjelje u listopadu i zadnje nedjelje u ožujku i tu nema ničeg neočekivanog i nepredvidljivog. Ljeti mi (zapravo i veći dio proljeća i pola jeseni jer ljetno vrijeme duže traje) dolaze obavijesti da se nešto događa u 16:00 GMT+1 iako je naravno pisac htio reći da je događaj u 4, a ne 3 PM. I sad, ili ga čekam sat vremena ko budala ili je lik zapravo dobro mislio, pa zakasnim, a nekad nam je nešto toliko važno da ćemo čekati i sat vremena, a ne riskirat da zakasnimo koliko god vjerojatno bilo da je ovaj mislio na kasniji termin. Raja se ponaša kao da smo sada na prirodnom računanju vremena, i sad u vražju mater sudbe li klete skraćujemo dan! Ne znam šta se nitko nije zapitao kako to da sjene iza podneva ne padaju na jug za vrijeme ljetnog vremena… Kad u školama uče računanje vremenski zona, samo se dodaju dodaje/oduzima jedan sat za svakih 15° geog. širine kao da cijeli svijet (jednako) računa ljetno vrijeme ili ono uopće ne postoji (ne bih sad da su neke zemlje same po sebi u krivoj zoni, tako da npr. u Parizu i Madridu nikad nije sat vremena manje nego kod nas 🙂 ). Lijepo se provedeš ako bi na taj način sutra računao vrijeme u New Yorku s kojim je razlika uglavnom 6 sati, ali je sljedeći tjedan 5 sati jer se Ameri tek sljedeću nedjelju vraćaju na zimsko vrijeme. A tek zemlje s ljetnim vremenom na južnoj hemisferi… Razlika sa Sydneyjom je trenutno 9 sati. Od sutra pa do kraja ožujak razlika će bit 10 sati, onda tjedan-dva opet 9 sati, a onda 8 i tako u krug.
I meni ovo pomicanje sata isto diže živac [pogledaj satove na naslovnoj slici, a imam još dva ručna, samo, srećom, riknule im baterije 😀 ] , ali se malo informiraj. Nemoj mi onda plakat da bi u kolovozu bio na plaži do 8 sati, ali je mrak. Ako pak cijelu godinu budemo na ljetnom vremenu, nemoj plakati da se sunce zimi ne pojavljuje do 8 ujutro. Nemojte zaboravit da mi možda jesmo mala zemlja za razliku od Rusije, ali se zato trebamo prilagodit Europi. Baš bi bilo zgodno da prelaskom granice sim i tam svako malo moramo pomicat sat… A kako bi tek turisti uživali u posjetu Lijepoj Našoj 🙂
Ukratko, jedini pravi problem je da ljetno vrijeme više nije ljetno. Sunce ti kalajisano, duže je od zimskog (standardnog). Koliko mi već ide na živac što na posao krećem po mraku. Slično, kad na proljeće prijeđemo na ljetno vrijeme, taman se naviknem da mi bude malo dana ujutro i eto ti mrklog mraka! Istina je da sam zahvalan da ljeti ne sviće u 4, ali što je prerano je prerano. Tako da molim lijepo da ljetno vrijeme ne maknete, ali ga skratite 🙂

Ovo o “poznavanju kurca” govorim iz iskustva. Dok sam kurca znao o ljetnom vremenu i sam sam u njemu vidio samo pomicanje sata i to mi je išlo na živce i samo zbog toga sam htio da se “pomicanje sata” ukine. S “kurcem” sam se dugo družio i o ljetnom vremenu ništa nisam znao godinama. Niti su ga spominjali u školi niti na faksu. Inače, faks o kojem govorim je geografija, tako da je to dosta žalosno. Zapravo, sjećam se da je na prijemnom bio zadatak s računanjem vremenskih zona na gore spomenuti način. Šterc nam je samo jedan sat filozofirao o ljetnom vremenu zato što smo imali slobodno predavanje nekoliko dana nakon pomicanja sata koje nas je potaklo na tu temu. Baš me to predavanje ponukalo da se malo informiram o temi. Ukratko, ljetno vrijeme nije nikakva znanost, ali se (prije prigovaranja) sam moraš informirati; ne možeš računat na (hrvatski) obrazovni sustav 🙂

Kad sam već kod obrazovnog sustava i pomicanja sata, da dotaknem s tim povezamu orijentaciju (pomoću Sunca) 😀 Stalno čujem komentare Ova današnja mladež se ne zna ni orijentirat pomoću Sunca… E pa, koliko se sjećam u školi samo trube Prijepodne je sunce na istoku, u podne na središtu horizonta, a poslijepodne na zapadu. Znači, po zimi je sve to super, samo se smrzneš u šumi 😉 a ljeti se izgubiš u šumi jer si u pola jedan vidio Sunce na “zapadu” 😀 Pravo me zanima da li isto sranje prodaju djeci u Saskatchewanu (provincija u “središtu” Kanade) koji je cijele godine na ljetnom vremenu. Em su zime u Saskatchewanu hladnije nego kod nas, em tamo ima puno više šuma nego u Hrvatskoj; tako da jadni Saskatchewančići stvarno jebu ježa i zimi kad se pogube u šumi ×D

U svem tom džumbusu s pomicanjem sata, samo mi jedna stvar nikako nije jasna. Mkay, noćas su vlakovi stajali sat vremena da bi se vozni red uskladio sa zimskim vremenom. Ali šta rade na proljeće?! 😮 Ubrzaju sve da bi nadoknadili jedan sat?! Molim službeno objašnjenje iz HŽ-a 😀


Objavljeno 30. 10. 2016. godine prijepodne u 11:38

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Time what is time

In case you didn’t know, UTC (Coördinated Universal time) and GMT (Greenwich Mean Time) are one and the same. I thought that everyone knew that, but recently, I spoke to people who find UTC confusing.

Content

For quick navigation through the rest of the post use Ctrl+F codes:
Is there any difference? Why the hell use two terms?! (cf1)
The abbreviation UTC (cf2)
Other names for GMT (cf3)
Time Zones (cf4)
GMT difference (cf5)
Daylight Saving Time (DST) (cf6)
Calculating and converting time (cf7)
THE POINT IS THAT GMT AND UTC ARE ONE AND THE SAME (cf8)

Is there any difference? Why the hell use two terms?! (cf1)

GMT is based on the local time at Greenwich observatory, near London. Hence the name Greenwich Mean Time. Greenwich is still used as the point through which 0° of longitude passes (yes, longitude is not strictly defined and Greenwich was just chosen for 0°).

Anyway, in the 1970s with the advancement of space technology, the use of satellites in calculating time more precisely began. Thus UTC was born. So UTC is based on GMT and isjust more precise. While there is a difference between GMT and UTC, it is disregarded in practice because the difference is like a nanosecond (satellites are more precise than an observatory on Earth).

GMT should have been abolished when UTC was introduced, but it wasn’t. Although, UTC is used for official purposes, GMT is still widespread. I dare say that it’s even more used. That is why I say “GMT” in the end of a post. WordPress, on the other hand, says “UTC”. That’s why time in the comments is displayed as something UTC+1/+2 (jump to cf6 to see why UTC+1 and UTC+2).

The point is that GMT, or UTC if you prefer, is international and, therefore, should be used always when there’s a possibility of that which you are referring to to be of global interest because we live in the world in divided into two dozen time zones and using GMT is the only way to prevent confusion. Every one should know the GMT difference of the time zone he lives in.

So yeah, GMT should have been included in this add of the live stream of The Desolation of Smaug première, which, by the way, sucked ass (the stream, not the movie). Not only that GMT was not included, but local abbreviations of time zones were used instead of GMT differences (jump to cf5 and cf7).
Nope, including GMT ain’t hard at all, yet again people are often too selfish to think about people outside their country or region, so crap like in the Hobbit add is common.

The abbreviation UTC (cf2)

As you can see, the abbreviation UTC is a little “clumsy” since the full name is Coördinated Universal Time, which would suggest CUT.
The French name is Temps Universel Coordonné, of which abbreviation would be TUC.
UTC was chosen as a compromise between CUT and TUC.

Other names for GMT (cf3)

What is the human nature? To complicate every little thing. Therefore, there are other names for GMT, none are used much outside a certain profession though.

One such name that I find shiny is Zulu Time. It’s not connected with Zulu people nor with Zulu language.
Zulu is a military name of the letter Z. NATO has a need of a quick reference to the international time zone. Z is the solution since it is only one character. You might encounter, dunno, 00:00z somewhere. It means 12:00 AM GMT and that the author was in a hurry. That is shiny in written language, but I do wonder how saying Zulu is quicker than saying GMT… or UTC.

Time Zones (cf4)

The Earth is divided into time zones. Officially, each time zone is covered by 15 degrees of latitude. Each time zone is based on the local noon of the central meridian of a time zone. Local noon is the time when the sun is in its highest position. The sun is in its highest position at 12:00 PM only at central meridians. The offset with the local noon can technically be only 30 minutes. For example, the central meridian of my time zone is 15°E. 16°E passes through the town I live in, meaning that local noon here is at 11:56 AM [during standard time, 12:56 PM during DST (jump to cf6 for DST clarification)].

I used the words officially and technically in the previous paragraph. That’s because, time zone borders are usually defined politically and follow a political border. A good example is Germany, which mostly lies in Central European Time Zone (GMT+1), but the westernmost parts of the country lie in Greenwich Mean Time. The whole country observes GMT+1 [+2 during DST (jump to cf6 for DST clarification)].
There are even territories that mostly or totally lie in a time zone different from which they observe. Central European Time seems to be very popular in Europe and seems like everyone wants to be in the time zone. Spain, Andorra, France, Monaco and Benelux are all in Greenwich Mean Time Zone yet they observe Central European Time. Okay, a few places in easternmost France do lie in Central European Time Zone, but the rest…

In the Pacific, countries chose to stay on certain side of the Date Line. New Zealand should be observing the easternmost time (GMT+12). Yet again, Christmas Island, Kiritimati, observes GMT+14 although it lies in GMT10 time zone. Basically, there are roughly 26 time zones currently and that might change at any time ’cause you never know when officials of a territory are going to decided to mess up the time zones. Just a few examples are Russia, which just abolished two time zones and China, a massive country that observers time of a single time zone (China Standard Time, GMT+8).

GMT difference (cf5)

Each time zone has its GMT difference or UTC offset. That’s why time zones are labelled GMT-8, GMT-5, GMT, GMT+1, GMT+9, GMT+12 or UTC-8, UTC-5, UTC, UTC+1, UTC+9, UTC+12 etc. If everything were perfect, with the rule that each time zone covers 15°of longitude, there’d be all in all 24 time zones ranging from GMT-12 to GMT+12. Each time zone west of Greenwich is labelled with a minus (hence GMT5 for New York) and east with a plus (hence GMT+1 for Berlin) because as you go east you add an hour and as you go west you take an hour. Note that local time zones may have GMT difference in hours and minutes, mostly hours and 30 minutes (e.g. India – GMT+5:30).

Time zones usually have abbreviation(s) other than just the GMT difference. Eastern American Time is EST (GMT-5), while Central European Time is CET (GMT+1), however GMT differences are preferred because you might not know the abbreviation and maybe even wouldn’t know where to start from. People usually recognize, dunno PST, EST and CET, but do you know what time zone JST is?

Daylight Saving Time (DST) (cf6)

Many countries or parts of countries observe DST, especially those in Temperate Latitudes. The point is to save daylight because daylight length varies a lot throughout the year in Temperate Latitudes.

How efficient DST is ain’t the topic of the post. I think I mentioned DST a lot in this post.

Anyway, DST is adding an hour to local time. Basically, local noon occurs at 1:00 PM instead of 12:00 PM at the central meridian. The names of the time zones change then. For example, Pacific Standard Time (PST) becomes Pacific Daylight Time (PDT) while Central European Time (CET) becomes Central European Summer Time (CEST). Although the same abbreviations are often use which only adds to confusion 😮

DST is variously observed in different parts of the world depending on the continent or the country. For example, DST in North America starts on the second Sunday of March and lasts till the first Sunday in November. In, Europe on the other hand, DST starts on the last Sunday of March and ends on the last Sunday of October. That’s the same every year, so don’t act surprised when the it’s time to move your clock.
It’s totally opposite on the Southern Hemisphere where the seasons are opposite.

The point is that GMT is not affected by DST. That’s why Pacific Time changes from GMT-8 to GMT-7 during DST and why Central European Time changes from GMT+1 to GMT+2 during DST.
The UK, on the other hand, which lies in Greenwich Mean Time… observes DST and during DST its time becomes British Summer Time (BST) which is one hour ahead of GMT.

Ironically, DST often lasts longer than standard time. That’s the case both in Europe and in North America, especially in North America.
So, time in the UK is often not GMT.

Summer Time is a term used for DST very popular in Europe (hence Central European Summer Time and British Summer Time). That term makes no sense because DST often lasts longer than just in summer (as I said, Europe itself is an example…).

Calculating and converting time (cf7)

They make it sound so easy at school. They give you the coördinates of two places and time in one, so you have to calculate the time of the other place. You base your calculations that 15° of longitude covers one time zone, which is one hour. Now, that is all well if the place(s) are exactly in the correct time zone (e.g. Paris is not) and if there’s no DST.

If the GMT difference (accompanied by the correct DST setting) is used to abbreviate time zone, all is indeed simple. All you have to do is subtract two numbers. That’s why I said that GMT difference should be used in abbreviating a time zone. However, crap like EST, CET, EET… is often used. That is especially confusing when DST is in effect, but not marked in the abbreviation (you can often see CET in July).
Lemme use Berlin and New York for an example again: Du bist ein Berliner und all of a sudden you wanna know what time it is in New York. You know the GMT difference of your time zone (you should know that whether you’re a Berliner, New Yorker, Moscower, Tokyoer or any other -er 😉 ), but you don’t know the difference between Berlin and New York, and all you have is the abbreviation EST. What the hell can you do with that?! However, if you had the tag GMT-5 instead of bloody EST, you’d know the difference between New York and GMT is five hours. Since Berlin is one hour ahead of GMT (GMT+1), you could easily say: Aha! 5+1, the difference between Berlin and New York is 6 hours! So if it’s 11 AM in Berlin, it’s 5 AM in New York (not necessarily though – scroll down a bit).

When I see that the live stream of The Desolation of Smaug is at 6:30 PM PT, I can make a reasonable assumption that PT stands for Pacific Time (which is usually abbreviated to PST or PDT…) because the première is going to be in Hollywood, which observes that time. However, when a seven year old Hobbit fan sees that the stream is at 6:30 PM PT… You can teach a seven year old tu subtract a few numbers, but you can’t expect him to know in which time zone Hollywood lies and how the time zone is abbreviated!

The easiest way to convert time is definitely a time zone converter. Although subtracting is quite easy, there’s less of a chance you’re gonna mess something, especially if the time difference is big and ranges from west of GMT to east of GMT [e.g. LA (GMT8) to Berlin (GMT+1) (Berlin again! Gosh, I must love this town 😀 )], if you just enter values in a time zone converter. That’s why, I always say Use Time Zone Converter to quickly convert the time under the GMT time I write.

Most converters can search cities. This eliminates the DST confusion since a decent converter should count DST according to the local DST rules. For example, if you want to convert 6 PM in Berlin to the local time in New York on March 15th, you’ll get the correct time of 1 PM because the converter knows that DST started in the US but not in Europe, so the time difference between Berlin and New York that day is 5 hours instead of the usual six.

Some converters, like the one on my cell phone, only deal with cities. So what if you want a specific time zone, say GMT? Search for a city in that time zone, of course. So, for GMT, we’re looking for a country that observes GMT all year round. One such is Iceland, so if you want GMT, search for Reykjavik. Note that London is not going to do it because the UK, unlike Iceland, observes DST.

Thank you for reading. If you wanna read more about time, you can read Time zones, my old post. Note that since I like typing 😀 I’m not sure how many things I said in both posts 😮

Well, in any case, despite these posts time is not the entity like it claims to be 😀
THE POINT IS THAT GMT AND UTC ARE ONE AND THE SAME!!! 😀 (cf8)

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Time zones

I know time zones aren’t totally geographically drawn and If you ask me, it’d be totally stupid to disregard political, administrative and economic characteristics (e.g. it would be idiotic to separate a country as small as Switzerland into two time zones just because westernmost parts of the country should geographically be GMT). However, current time zone divisions are extremely stupid in some cases. Lemme just to make a short analysis (yeah, when time zones are considered, this is short).

North America
A few US states and Canadian provinces are divided into two time zones where that’s totally unnecessary – only Ontario, Quebec, Canadian territories (expect Yukon which is in only one time zone 🙂 ) and Alaska are geographically wide enough to be divided into several time zones. I guess Texas is big enough to be in two time zones, but I’d put the whole state in Central Time Zone. True, Canadian territories are also quite wide, but, like Alaska, they’re so north that there’s no need for many time zones. Current time division of Canadian territories is fine. Now, what is also stupid is some part of a state or province/territory observing DST and some not. For example, Arizona and Quebec (if you ask me, whole Arizona should abolish DST since most of the state doesn’t observe it and the state is real south while whole Quebec should observe DST ’cause most of the province does) Well, the thing that makes the most sense to me is making a local time zone for Quebec (GMT-4:30). However, it’s logical to have (most of) Quebec in sync with the most populous parts of both Canada and the US, so the current time zone division should be fine. Ontario, another quite “wide” province, should either be divided into two time zones more “fairly” (a lot more province territory should be Central Time) or the province should be Eastern Time altogether (if Thunder Bay, which is a lot more to the west than Chicago, is Eastern Time, what’s the point of having a few minor settlements in the Central Time Zone?!). Suffice it to say, I’m for (a more fair) time division of Ontario. Oh, there is Newfoundland with its GMT-3:30. Now why the fuck isn’t it in the same time zone with (most of) Labrador, Nova Scotia, New Brunswick and Prince Edward Island?! Even more stupid is the division of Labrador – most of the region is GMT-4, but the southestearn tip is GMT-3:30. Basically, the GMT-3:30 time zone should be abolished altogether and the province Newfoundland and Labrador should totally be placed in GMT-4:00.
Now, let’s talk about Greenland. Surely it’s not populated much, but its inhabitants must be taken into account. Yeah, it is the biggest island on the planet and, geographically looking, it should be divided into several time zones. However, since it’s not populated much, a single time zone should be used to make life of the Greenland inhabitants easier. Basically, I’d abolish all time zones, but GMT-3.

Europe
Okay, France, Monaco, Andorra, Spain and Benelux (i.e. the Netherlands, Belgium and Luxembourg) have no place doing in CET (GMT+1). They say the economy keeps them in CET. Pure bull shit – first of all, there are the UK, Ireland and Portugal in GMT and they’re all developed countries; secondly, if all the mentioned countries switched to GMT, well each country would have six additional business partners (there’d still be plenty of developed countries in CET – e.g. Switzerland and Germany). So the economic reason is gone with the wind. In addition, if they’d switch to GMT (where they belong), the quality of life (mostly human and their pets’ since outdoor animals don’t care about time zones anyway) would improve ’cause GMT is natural for most parts of those countries (an exception is e.g. easternmost France) and thus the life would be healthier.

China
It is totally stupid for a country as vast as China (especially in width) to be in a single time zone. I mean what, does it like dawn at 10 AM in Urumqi just because whole China “must” be in a single time zone and Beijing (and surrounding places) is the privileged city?!

Australia
At first I thought things are pretty good in Australia, but come to think about it time zones of Australia are kinda messed up. First of all, all of Queensland should introduce DST, so the state is in sync with NSW, ACT, Victoria and Tasmania. Why the whole state? It’d be even more stupid if the state was (unnecessarily) divided into two time zones. The Northern Territory and South Australia should both use GMT+9. The difference with the most populous parts of Australia might be longer (i.e. 1 hour instead of 30 minutes), but it would be easier to convert local time to other times (including Eastern Australian Time). Moreover, such division would be more logical – time in Australia would be GMT+8, GMT+9 and GMT+10 (i.e. the difference of each time zone would be 1 hour – 1 hour ahead of Perth and 1 hour behind of Sydney when DST is off). Furthermore, DST in South Australia should be abolished to align the times of the Northern Territory (Northern Territory and South Australia would be one time zone) and Western Australia (the difference between West Australia and its eastern neighbours would always be an hour). Other anomalies should also be fixed. Basically, in my opinion, mainland Australia should be divided like this – Western Time (GMT+8) should include Western Australia; Central Time (GMT+9) should include Northern Territory and South Australia; and Eastern Time (GMT+10) / DST (GMT+11) should include Queensland, NSW, ACT, Victoria and Tasmania.
Why DST in Eastern Time and not in Western and Central? Simple: most of the Eastern Time Zone already applies DST – it is quite easier only for one state (i.e. Queensland) to adapt than for 4 of them (i.e. NSW, ACT, Victoria and Tasmania). Likewise, it’s quite easier for South Australia to adapt to the Northern Territory and Western Australia. Furthermore, the immense heat of central Australia is easier to withstand during night, so it makes sense that central parts of Australia have less daylight during most of human activity. Even northernmost South Australia is pretty much central Australia. Moreover, to maintain time sync of South Australia and Northern Territory, South Australia is the one that should abolish DST.

DST
A little more about DST now. DST observance is totally up to a country/territory. It seems useful to me only in temperate latitudes. Just be coherent with DST – let’s take the mentioned Arizona as an example. I think the whole state should abolish DST. That’s my opinion. For all I care, the whole state can observe DST, but it’s totally stupid to have the state (a single administrative entity) divided. Just like Australian time zones should be in DST sync. Same shit is in Canada where some parts of a province/territory observe DST and some don’t. I mean such things are unbelievable to me – someone close to you (a relative or a friend; maybe even best bud) lives just a few metres away in the same province (US states and Canadian provinces/territories are equal to European countries) and you have to adjust your clock for every bloody visit…
Furthermore, I think DST applying should be aligned on each hemisphere respectively (i.e. the DST beginning and ending should be on the same date in North America and Euroasia on one side and in South America, Africa and Oceania on the other).

I agree that local population’s opinion is the most important when dividing areas in time zones, but some basic logic ought to be used.

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