I am a little late in this thread, but I try to put this wikipedia DST graphic up whenever I can.
It really helped me understand the sunlight graphed over the year and DST.
That’s a great chart but I want to talk to the ding dong that represented sleep hours as the white band and daylight hours as the dark bands.
There is a proposition on the California ballot to allow year-round DST. The pro arguments center around scientifically dubious claims of increased health problems and lost productivity after time changes. The con argument is, “It’ll be dark in the morning!”
Personally, I don’t really care either way, but I’m voting no because I’d rather the question were settled on the federal level. The whole country changes or the whole country doesn’t.
The US Navy had in the 1970s “a way” of dealing with time zone shifts. My ship typically crossed between Norfolk and Rota (near Gibraltar) in six days.
Travel East Coast United States to Gibraltar involves six one-hour shifts of the clock, so during the eastward transit ship’s time was adjusted each night at 2:00 AM. So the crew lost an hour’s sleep each night, but those on the midwatch (midnight to 4:00 AM) only had to stand a 3-hour watch those nights.
On the return transit to Norfolk, ship’s time was adjusted at 2:00 PM. So those six work/non-work days were each one hour longer than the previous day–the crew got to work an hour longer. (Yes, those on the afternoon watch might have stood a five-hour watch from noon to 4:00 PM). I guess it all got worked out.
We did not use ZULU (UTC) time except operationally, to maintain synchronized time management.
Yeah, me too. I hate standard time. Standard time means it’ll be dark next month long before I get out of work…at 4:30pm. The buses here literally pick up every kid in their own driveway, so the whole ancient “it’ll be dark when kids go to school!” argument doesn’t sway me in favor of keeping standard time.
I’ve always been honestly confused about how the day is of such different lengths. I’ve heard that it always gets dark at 7pm in Florida even in the summer, and your comment surprises me too because we do observe DST and 9:30 is about when it gets dark here too.
Actually, the dark bands are the night. Note that noon is the middle of the light portion.
They made it somewhat confusing that they talk about the “sleep cycle” in the lighter day areas. I think they just needed a place to put words, so they put it there.
According to the LunaSolCal app on my phone, Sunset in Miami FL in August is at 8:49 with Sunrise at 6:49. Length of day is 13h 14m
When I lived in Indiana in the 90s, the counties by Chicago would observe daylight saving time because Chicago did and it was the center of their universe for the most part. The rest of the state did not. For part of the year I would be on the same time as my family back East and for part an hour off.
My DVR got seriously confused when trying to record a program around the time of the DST change last weekend - when I got up in the morning, I found that it had started to record at the right time, but never stopped, so I had 8 hours recorded instead of 1 (and if I hadn’t noticed then, I would have had more…).
Kinda like the What Time is it Right Now? app in Bojack Horseman. For those who have not seen the show, it’s just what it sounds like: You unlock your smartphone and start the app; it displays the time.
I think what’s confusing is that the chart is “upside down.” That is, the progression of the day is going from bottom to top. Note that “Wake up” is toward the bottom of each chart, below noon, and “Go to sleep” is at the top of each chart. So the bottom of the charts represents morning, and the top represents evening. Weirdly laid out.
Back when we were first starting to use Unix for production, I had to have long discussions with people about how batch processes that we needed to run once a day/night should not be scheduled via cron between 01:00 and 03:00, lest they run twice or never on change over days. And yes, using cron (and particularly on local time) was not a smart choice, but we were new in the environment.