Today at 2:00 am is when the US changed from Daylight Savings Time to Standard Time which required shifting clocks back by one hour. It is also the cue for many (including me) to grumble once again about this clock adjusting process that takes place twice a year. I went around changing all eight clocks last evening and then a few minutes later, there was a brief power cut, which meant that I had to again set the time on four clocks that are plugged in.
Not every part of the US changes times like this, with some staying on Standard Time all year round.
Exceptions include Arizona (except for the Navajo, who do observe daylight saving time in Navajo Nation), Hawaii, and the overseas territories of American Samoa, Guam, the Northern Mariana Islands, Puerto Rico, and the United States Virgin Islands.
I grew up near the equator where the amount of daylight stays pretty much the same throughout the year. and thus does not require fiddling around with clocks twice a year. But irritation with the practice is growing in the US and arguments for keeping one time throughout the year seem to becoming more frequent.
But even when there is agreement on the need for keeping the time standard fixed year round, there remains disagreement with whether the single time should be Daylight Savings Time or Standard Time. Business interests, especially in the recreational world. tend to favor DST because the long evenings of daylight are more conducive to people indulging in outdoor activities after work and school. The golfing community particularly likes it and they are a highly influential lobby since so many of the rich and powerful indulge in this pastime.. But parents and educators tend to favor Standard Time so that children are not having to go to school in the dark in the. cold winter months.
In a surprise move, in March of this year, the US senate passed a bill proposed on the floor by Florida senator Marco Rubio that would fix DST as the time all year round, and it passed unanimously without any hearings. The changes would take effect in November 2023. The bill never became law because the House of Representatives has so far not even agreed to take it up.
The quick and consequential move happened so fast that several senators said afterward they were unaware of what had just happened.
…Congress tried a permanent daylight saving time in the 1970s, but quickly reversed course on the move amid widespread public outcry over the switch.
The latest attempted switch will only get to President Joe Biden’s desk to become law if the House acts on the measure, and that chamber’s plans remain unclear. [Sen. Roger] Wicker said he expected the House to pass it and Biden to sign it, but one person familiar with the matter said there was no clear agreement between the Capitol’s two sides at the moment.
There are suggestions from medical research that Standard Time is better for us because it is more aligned with our circadian rhythms.
Very recently, the European Parliament, called to decide on possible abolition of the Daylight Saving Time (DST), approved a resolution calling the scientific community to conduct a more in-depth evaluation. The question is based on disruption of body’s circadian rhythms. We review here the relationship between DST and cardiovascular health. The available evidence suggests the existence of an association between DST and a modest increase of occurrence of acute myocardial infarction, especially in the first week after the spring shift. Possible mechanisms include sleep deprivation, circadian misalignment and environmental conditions. The role of gender and individual preference in circadian rhythms (chronotype) will need further assessment.
Arguments in favor of adopting DST all year round have been criticized.
The US has previously tried and failed to maintain daylight savings time year round. People have claimed that it would reduce energy consumption, maximize daylight, and provide more time for both productivity and enjoyment of the day. Yet, data does not support the fact that following DST has led to significant energy conservation, and following DST year round would not maximize daylight in any season other than Summer. Furthermore, experts in sleep medicine fiercely disagree with the decision to keep daylight savings time over standard time. While a number of practical, legal, economic, and safety considerations fuel this debate, the crux of the issue, and the science behind the right answer, hinge on the circadian rhythm.
There is of course the option of splitting the difference and setting the clocks halfway between the two time standards. This would mean that US time would be off by a half-hour from most of the world which would be a little awkward. But some countries do not seem to be bothered by that (or even by quarter-hour shifts, as is the case in Nepal) and even within countries, there are zones that are off by half an hour, with Australia being a notable example.
My country of origin Sri Lanka is off by half an hour and I blogged in 2006 (scroll down) about how the government changed its time by half an hour to make it on the hour. That change was fought by some members of the Buddhist clergy for the most farcical of reasons. They claimed that the shift resulted in the country’s ‘spiritual plane’ (whatever the hell that is) shifting to now lying in the Indian Ocean, causing all manner of natural disasters such as the deadly tsunami in 2004. But they were were powerful enough to force the government to reverse itself. It would not surprise me in the political climate that we have in the US today for any move to change the current system to also be denounced by the loony conspiracists, suggesting that it is part of a secret plot to undermine the precious bodily fluids of real Merkins.
The globe is split into 360 degrees for its 24 hours which gives each degree a shift of 4 minutes. Hence a shift in longitude by 15 degrees corresponds to one hour in time. Most countries pick the nearest hour longitude as their time, and if the country is large enough, have different time zones for each 15 degree shift. China is notable in that in 1949 it adopted just one time throughout the country, even though the width of the country spans five hours of time zones.(For an alternative explanation of how time zones work, see today’s Non Sequitur cartoon.)
billseymour says
Calling it “permanent daylight saving time” is just a convenient way to explain the change to folks who don’t really understand all the complexities of civil time throughout the world. What would actually happen is that we’d have a new standard time with no observance of summer time at all. Also, states would probably continue to be allowed to select a more westerly time zone if they wanted to. For example, Arizona could well decide to observe the new Pacific time and so stay at UTC−7:00. (The Navajo Nation would probably move to UTC−6:00…Native American reservations are allowed to select whatever civil time observance they want.)
If the elephant in the room goes through with it, the rest of North America (except Greenland) will probably follow in self defense. Indeed, México has already begun to make the change (although, IIUC, it’s not final yet).
I’m not sure what would happen to Atlantic standard time, currently UTC−4:00. Would Puerto Rico and the U.S. Virgin Islands switch to −3:00? I’d guess not since they don’t observe DST at present.
Sorry if that’s more than you wanted to know. I’m something of a civil time geek. 😎
larpar says
My clock/radio automatically changed 2 weeks ago, the rest of the world has finally caught up. : )
SchreiberBike says
It amazes me that we can agree to change the time of day arbitrarily, but we can’t seem to change the time when schools and businesses open and close. If people want more time in the evening, why can’t we go to work earlier and if schools want daylight when the kids are walking to school, they could change their hours. I never know what is set in stone in this country.
Jörg says
For clocks that you don’t have to set regularly, look for “atomic clock” or “WWV clock” at your favorite electronics dealer. … Altough, prices seem to be quite steep in the USA, about double the European prices.
Katydid says
@3; I was told that the local high school (population 4200) cannot POSSIBLY start any later because the 20-person foooooootbaaaaaw team needs the extra daylight to practice. So schools must start at 7 am (and the school buses start picking up kids around 6 am) and end at 2 pm, with the kids home before 3 and the parents not home from work for hours. The high school has a huge sportzballz palace with a bank of bright lights the football team could use to practice, but no, the convenience of a 20-person team outweighs the physical health of the other 4100+.
jimf says
This is a topic I have followed for some time (including writing an article about the prior change, circa 2007, for the now defunct Seed Magazine, the parent of ScienceBlogs, which in some respects was the parent of FtB). Anyway…
I find it amazing that there is seldom anything that Congress can agree on, yet this sails through the Senate unanimously. I am a believer in the dictum that things only happen in the US when someone stands to make a lot of money from it (and no one stands to lose money). Now for some fun details. I haven’t checked to see if these numbers have changed recently as these data are from a few years ago, but I suspect they are still valid.
It is common to see two items reported in the news regarding time change: 1) There is a measurable increase in cardio events (and associated death) in the days immediately following the change in the spring, and 2) A sizable majority of people do not like changing their clocks twice per year. What the reports seldom mention is that there is an equal-sized drop in those events/deaths in the fall (which implies that a lot of people are overworked). Regarding the second item, while it’s true that 2/3rds don’t like changing their clocks, they are split roughly 50/50 on keeping standard time or daylight saving all year. That means the breakdown is roughly 1/3rd keep it as it is, 1/3rd change to DST all year, 1/3rd change to ST all year. So why the sudden and unanimous push to keep DST all year if only a minority want that?
Next, the support for year round DST or ST falls once it’s implemented. IOW, people don’t appreciate what it will be like when there’s no clock change. I was in high school when the US did this for one year (in response to the “Arab Oil Embargo” of the early 70s as I recall). People were on board with it when it was proposed, but in the weeks and months that followed, pretty much everyone hated it and wanted to go back to the clock change. Very quickly, people got tired of commuting to work or school in the dark. It didn’t matter that they had some extra light at the end of the day. What mattered was that they started their day in the dark, and if they worked inside, had artificial light all day, and then if they had O/T, drove home in the dark anyway. For the most part, the only USAians who have a good memory of this are those aged 60 and above. As a student, I was looking forward to the extra hour of light at the end of the day, but walking to school in the dark got depressing very quickly (and dangerous). A long walk to school in upstate NY in January/February is no treat, but doing it in the dark sucks.
Of course, I live in the northern part of the US, not far from the Canadian border. DST in the summer is great because it’s still light outside at 9 PM and the sun is still up well before 6 AM. But in the winter, DST is terrible. And ST in the summer is now fun because, besides losing the hour in the evening, the sun is up literally hours before I get out of bed, which means I won’t be sleeping. Now folks who live along the southern border, from So. Cal. to Florida, don’t see those extreme changes, and maybe for them, full time DST might seem like a good tradeoff. I get that. And money is to be made according the sports equipment manufacturers, because people (at least in the south) are more likely to be outside and doing things that need said equipment. And so, I suspect, permanent DST may come to pass, not because a clear majority want it, not because it will save energy (studies have shown it won’t), not because it’s safer (some studies indicate it’s less safe), but because money is to be made, and no one stands to lose money in the process.
jimf says
@3
Many years ago I worked at a large company that had “summer hours”. You could opt to come in an hour early so you could leave an hour early. Being young guys, two friends and I opted for this and we began our day at 7 AM. Bonus: not only was it light outside when we got up, but the commute traffic was noticeably lighter, we got the best parking spaces, and our building was quiet and peaceful when we walked in (no morning crush).
jimf says
Forgot one thing: There is one advantage from all year ST that I would enjoy. Every summer, when the articles come out about avoiding being in the sun and/or wearing sunscreen during peak sun hours, stating those hours as “10 AM to 2 PM” would finally be correct. Under DST, solar noon is at 1 PM (if you’re at the center of the time zone), and thus the peak hours are 11 AM to 3 PM.
Oh, and Katydid, of course! Sportsball, especially HS fooootbaaaw, is the single most important thing that is or ever could be. All I have to do is look at the headlines in my local paper or watch the local nightly news to be reminded of that. Priorities, people!
xohjoh2n says
DST is great! It neatly divides a large part of the politically outspoken classes into those who care very deeply that it should be abolished, and those who care deeply that it should be preserved, who then spend a large fraction of the year arguing bitterly at each other about something that if they actually considered it would realise that in the grand scheme of things it’s a matter of almost no importance whatsoever. (Especially given that when pushed they will both be forced to admit that whatever number you assign to a particular point in the day is completely arbitrary.) Certainly the opposition is sufficiently finely balanced that it will probably never make any progress.
Meanwhile the people at the top have no real intention of doing much about this: the distraction is great for them as it prevents you from noticing their hands in your pockets or doing anything effective about it.
(PS You’re such a backwards country! In the UK we changed last week!)
Tabby Lavalamp says
My province had a referendum in a recent election about abolishing the time changes and going to permanent DST. The No side won, but I wonder if that would have been a different result if it was about moving to permanent Standard Time. I know it would have swayed my vote because it was the permanent DST I objected to.
anat says
I lived with ST all year in my childhood (in Israel) and hated it. People complained that with the sun being up early in the summer they woke up too early (due to both light and heat) they were sleep deprived. And this was in a country where schools and most work places started at 8 am. People preferred switching twice a year to that.
billseymour says
jimf @6:
Actually, it’s often OK for poor people to lose even more money (I’m sorry to say).
Holms says
The purpose of the clock is to give information about the progress of the day/night cycle. Midday gives the solar meridian, and midnight the nadir. Obviously this will have some inaccuracy due to the width of the time zones and our position within them, not to mention the odd shapes many of them have. But the awkwardness caused by start and close times of schools and businesses can be solved by a simple method: change the damn open and close times! Making clocks permanently wrong is really the worst path to choose.
Pierce R. Butler says
xohjoh2n @ # 9: … whatever number you assign to a particular point in the day is completely arbitrary.
Putting 12 o’clock noon at the time the sun is highest on any given day has a good basic rationale (unless you switch to, say, a metric-friendly 10- or 100-hour schema).
John Morales says
I used to live in South Australia, which does use daylight savings.
Now I live in Queensland, which does not.
As I write, these are the respective daylight hours (dawn till dusk, local times):
Adelaide SA 5:40 am ↔ 8:18 pm
Brisbane QLD 4:27 am ↔ 6:35 pm
I have, of course, adjusted.
John Morales says
Holms:
Might as well claim the purpose of a calendar is to give information about the progress of the year cycle, so, too vague and insufficient; I think it’s to keep track of time, which is helpful in many ways quite independent of the day/night cycle.
Presumably, one would change them on an ongoing basis to match the actual cycle and duration — any less often, and the clocks would be mostly permanently wrong.
By a minute or so, admittedly 🙂
Holms says
#9 xohjoh2n
I think you and I have a different understanding of the word arbitrary. For my money, matching the clock to an external pattern is the exact opposite of that.
___
#6 jimf and #11 anat
Why are people so committed to having schools and businesses open at the exact numerical mark year round? And why do they then insist on hauling the numerical system of time keeping forwards and backwards twice yearly for convenience? Why not keep the clocks as accurate to the cycle of the day as possible, and change business and school opening times instead?
Silentbob says
@ 13 Holms
What utter bollocks! Explain how a clock tells you when it is sunrise or sunset.
Under our arbitrary 24 hour system this means there are precisely 12 meridians along which one has to be precisely located in order for this to be true. In other words, you’re quite happy with almost all the Earth having “inaccurate” time, as long as we don’t call it daylight savings.
Bwahahahaha! X-D
So according to Holms, in order to avoid the inconvenience of changing the clocks in a universal fashion from one arbitrary time to another arbitrary time once a year, we should have 10,000 schools and businesses all setting their own times of operation when they feel like it. So convenient!
@ 17 Holms
Dude, days being significantly longer in summer than winter at higher latitudes is an external pattern. Daylight savings is literally an exercise in matching timekeeping to an external pattern, you utter spanner.
I’m always amused to find professed ‘atheists’ who treat arbitrary conventions like timekeeping as though they are inviolable holy writ. Holms, there is no such thing as ‘correct time’. There are various methods of timekeeping that have greater or lesser utility. That is all. None is more ‘correct’ than the other. The universe doesn’t give a fuck whether you call the solar zenith 12 pm or 1 pm. Get over your quasi-religious hang up that you’re somehow sinning if you do such a thing. To misquote the bible, “The clock was made for man, not man for the clock”. The only timekeeping system we are obliged to use is the one we find most convenient, and for (I think) most people above the Tropic of Cancer or below the Tropic of Capricorn that’s one where there is more light in the winter evenings.
@ 9 xohjoh2n
I get this is a joke, but if you look at a globe, unless I’m mistaken the entirety of the UK is above the entirety of the USA. That is, it’s not a matter of being a more backward country, it’s a matter of being a more southerly country. How early daylight savings should start is a function of latitude.
Silentbob says
@ 15 John Morales
As fascinating as this information is, I’m curious if you had anything remotely resembling a point when you decided to share it?
Given that we know Qld is at a more northerly latitude than SA, and that day length is a function of latitude, and that daylight savings shifts daylight hours forwards -- what new information did you expect us to glean from your data?
John Morales says
Silentbob, it’s pretty simple.
Most people don’t get up around 4:30 am, nor do they retire for the night around 6:30 pm. It follows that they miss out on a shitload of sunlight time.
And business hours are the same (adjusted for local time)
Basically, in Adelaide (though the duration of daytime is actually shorter) most people get a longer experience of daytime, helped by daylight savings.
As for you getting “new information”, that was never the point.
The point is perspective.
I’ve lived through both regimes, both are amenable.
I suppose I should add that over the years (before the internet in particular) I’ve once or twice missed the changeover — the which means I was never that bothered by it either way.
—
So, your turn. As fascinating as your comment may be, do you have anything remotely resembling a point given you decided to share it?
What new information did you expect us (!) to glean from your wondering?
(Nice to know you’re still feisty. I’ve been a bit bored lately)
John Morales says
BTW:
Ahem. cf. https://en.wikipedia.org/wiki/List_of_countries_by_southernmost_point
UK:
Pednathise Head, Scilly Isles 49°52′N
Lizard Point (mainland) 49°57′N
USA:
Ka Lae, Hawaii (50 states) 18°54′N
Cape Sable, Florida (contiguous states) 25°07′N
(You are mistaken)
John Morales says
[To cross the t and dot the i, the northernmost]
UK:
Out Stack, Shetland Islands 60°51′N
Dunnet Head (mainland) 58°40′N
USA:
Point Barrow, Alaska 71°23′N
Northwest Angle, Minnesota (contiguous 48 States) 49°23′N
John Morales says
Oh, c’mon, Bob the Silent; I deliberately baited my comment(s) so that you would triumphantly pounce. A good set-up, I thought.
Anyway, next time. Hopefully.
sonofrojblake says
Nosing in…
Since any reasonable person would exclude Alaska from the conversation, and similarly would accept that although Silentbob said “the UK” they could reasonably be inferred to have meant “Great Britain” -- then the first quote is absolutely correct. But…
Eh? What does latitude have to do with it? The date of the equinoxes and solstices doesn’t vary with latitude. Daylight savings anywhere are only about acknowledging the approaching/receding winter solstice, and adjusting the point we use to denote when noon/midnight is so we can avoid the bother of having to change things like the times the pubs close while making it so that kids can walk to or from school in the dawn/twilight, or whatever, instead of absolute dark. How early daylight savings starts is a matter of politics, unrelated to the physical universe.
Ultimately, unless you’re near the Tropics, someone is going to be inconvenienced by shorter days, whether by later sunrises or earlier sunsets, or conversely someone is going to be inconvenienced in summer by longer days, whether by earlier sunrises or later sunsets. Some miserable fucker is going to complain no matter what you do, so short of adjusting the axial tilt of the earth to eliminate seasons altogether, it’s just a case of whose bleats you want to ignore. It’s politics, and as xohjoh2n pointed out, it’s a nice meaningless distraction from all the other stuff that actually matters.
John Morales says
sonofrojblake, oh well, you’ll do. I’m in a mood.
But of course! “the entirety of the USA” should exclude its largest state.
Everything but that, that’s the go!
Heh. Not “Little Britain”, then?
So.
Daylight savings is not something that actually matters. In your estimation.
(Still, you are weighing in)
I’m not ignoring your bleating, am I?
(Of course, you’re not complaining about others complaining.
Perish the thought!)
sonofrojblake says
I’m not complaining, or bleating, at all. Change the clocks, don’t change the clocks -- I don’t really give a monkey’s. It’s a minor inconvenience either way.
Yes, the entirety of the USA obviously doesn’t include Alaska, since the subject in question is “daylight saving”, and Alaska (a) has only been a state since the 1950s, (b) about 20% of it is above the Arctic circle. If it’s not obvious that Alaska is in a sufficiently unusual position that it should be excluded from this conversation, I’m not sure there’s much that can be done for you.
I have no idea what this response means or how to respond to it. “Little Britain” is a racist, ableist, misogynist BBC comedy show from the 2000s written and performed by two extremely privileged white men. “Great Britain” is the “mainland” of the UK. I’m not sure what connection you’re attempting to make.
Katydid says
To continue with the school stories; in many places in the USA, the high school kids’ day starts first, and the elementary schools start last. In my particular area, the bus comes for the high schoolers around 6 am, which means most of the year, they’re standing in the dark at the bus stop anyway. The elementary school kids don’t start until 9 am, so they’re standing at the bus stop in daylight.
There are so many reasons that such an early start for teenagers is not biologically/chronologically appropriate. But nothing can be done, foooootbawwww, you know.
For adults, this means that the streets are clogged with buses making their rounds from 6 am -- 8:45-ish am. That means many people will try to beat the buses--it’s not unusual for office workers to start work between 5 and 5:30 am, or wait until the buses finish their slog and don’t start work until 9:30 -- 10 am. Nobody’s happy, and changing times only throws another layer of complexity into it.
Katydid says
A fun factoid the local news shared: shifting times according to the weather gave adults more daylight to work on their Victory Gardens during WWII. The USA got this idea from…the Nazis. I just googled that to be sure I heard it right: it’s on time and date dot com / daylight-savings-history.html.
I spent a huge chunk of my life in places that didn’t have the clocks change, like Hawaii, and I find changing clocks to be, well, STUPID. I agree with the idea of having “summer hours” and “winter hours” for school days, but it would probably have to be by tiers in the USA. In the deep south, school starts the first week of August and gets out in early May. In the far north, school starts in September and gets out in June.
Dauphni says
Bait or not, it’s fascinating to see just how close these two points are, considering that one minute of latitude corresponds to one nautical mile.
John Morales says
sonofrojblake:
You’re writing about it, and expressing a strong opinion to boot.
(But sure, others bleat, you just write stuff)
Right. It doesn’t really matter, yet here you are to make sure we all know your opinion about it. About something that you claim matters not to you.
Very credible, your claim — for certain values of ‘credible’.
Wow. OK, I wrote and deleted a few snarky retorts to that, but I can’t really beat that concept of the entirety of something “obviously” excluding its largest component.
Remarkable.
Yet you did respond to it. Having no idea did not faze you.
Impressive.
(Hint: Great vs. Little — it’s a super simple linguistic play.
Too simple for someone of your acumen, clearly — your mind is too finely attuned)
I know, I know. Shouldn’t punch puppies, shouldn’t bash babes.
Bad form.
(I know should not be having fun with you, but Silentbob — as usual — made himself scarce, and you are what remains. Already alluded to that, didn’t stop you. Didn’t stop me, either)
—
Anyway. To be on-topic, daylight savings does actually have merits and drawbacks, and is not an inconsequential thing, whatever you might think.
(Which I thought I made clear in my first comment, but then, for such as you it’s an obscure (heh) claim)
—
Katydid:
What?
Where the fuck is this place when office workers routinely start work at those times? I assure you quite definitively this does not (NOT) happen here in Oz.
Yikes! What a hellhole!
(Lemme guess, the USA, right?)
billseymour says
Could we please get rid of the innocent notion that civil time is some representation of physical reality? Mano can correct me on this, but the last I heard, there’s no equation that physicists use that has a variable for a point in time. The time variables are all about amounts of time.
Civil time is a cultural thing, not a physical thing.
Holms says
#18 noisy robert
It doesn’t. As I told you, it indicates the zenith and nadir of the sun’s track, at least at the center of the time zone. Sunrise and set are of course determined by local topography.
Sigh. We agree that there is inaccuracy due to the width of the time zone and your position within that strip. My point, if you care to pay attention, is that standard time at least has the benefit of minimising the error for all people. Daylight savings on the other hand solves the problem of early school mornings and similar by the stupidest means possible -- by increasing the error of time for all people.
My suggestion is that the schools and businesses simply change their hours. No need to divorce clocks from their original basis.
Katydid says
@John Morales; got it in one, I’m talking about the USA. Where does a ridiculously early start time happen? Well, I’ve worked those hours on the east and west coast and Colorado. Haven’t spent much time in “the heartland” so I’m not sure what happens there.
In short; jobs like software development lend themselves to flexible hours, and in places where the traffic outpaces the infrastructure and where people are crammed into undersized buildings, people will “flex” their time when they can to be most productive and/or fit their life requirements (e.g. kids in school, other obligations). It used to be more rare, but around 30 years ago, employers started allowing flextime, and since the pandemic, things are even more accommodating, which is great; 30 years ago I had a job at the state capital, 12 miles from home. If I left at 7 am, I’d get there around 7:20. If I left at 8, I’d get there around 9. I ended up quitting that job because the hours were inflexibly 9 -- 5 and I was spending at least 2 hours a day sitting in traffic, barely moving.
jenorafeuer says
Speaking as someone who has to program computers to deal with time, I would love if people got rid of DST, because it adds an extra layer of complication to things. The distance from 7pm to the next 7am is usually 12 hours, but on one day it’s 11 hours and on another day it’s 13 hours, and those days aren’t fixed. (In order to get the actual ‘time until next 7am’ I had to convert the current local time to UTC, create a local timestamp of next 7am with the DST flag set to ‘I don’t know, get the library to tell me’, convert that to UTC, and then take the difference between those two UTC times. Way more work than I should need to do. And that’s even after taking into account the maxim that if you want to deal with time on a computer, find a library that already deals with it and use that, because rolling your own is next to impossible to get right; there are just far too many exceptions.)
Also, at the very least, astronomers would hate it if it was ‘use DST all the time’ rather than ‘use ST all the time’. Though astronomers tend to have all their own timekeeping anyway because they kind of need to.
Katydid says
What #34 said. 100%
sonofrojblake says
All other nonsense aside, this does make the following pub quiz question possible: which is the longest month of the year?
At first glance it’s “hang on, aren’t a whole bunch of months the same length?”, but thanks to DST, October is always an hour longer than any other month.