Description: In most jurisdictions we recently “fell back” as we turned out clocks back an hour and returned to Standard Time after spring, summer and fall on Daylight Saving Time. What was somewhat different about this most recent “fall back” is that many states and provinces and countries are contemplating perhaps never doing that again and moving to and staying on Daylight Saving time. A choice opportunity exists in that we could decide to stay on Standard Time or move to and then stay on Daylight Saving time. The difference subjectively? Well, with Daylight Saving time we get daylight later in the morning and keep it longer into the afternoon or evening compared to Standard Time. Which would you prefer? You should, consider, in your reflection, how far north (or south) of the equator you live as the seasonal variation in Daylight “On” and “Off” times is greater the further you are from the equator. So, for example, on the equator the sun rises at 6 am and sets at 6 pm every day. By comparison, in San Diego on December 22 the sun rises at 6:47 and sets at 4:47 while in Calgary, where I live, on that same day the sun rises at 8:37 and sets at 4:32. So, if you focus on when we might think of daylight being personally usable (after work or after school) it would appear both Calgarians and San Diegans would benefit roughly equally from permanent Daylight Savings time. So, we should go for that right? Well, maybe think again. Think about what the difference might be between Social Time (Schedule) and Circadian Time (Schedule) and if you are not sure what that distinction might add to this question give the article linked below a read. Circadian science won a Nobel Prize a couple of years back so maybe there is some stuff there we really should factor into this question BEFORE we make a permanent time decision.
Source: Time to Show Leadership on the Daylight Saving Time Debate, Nathaniel F. Watson, Journal of Clinical Sleep Medicine, Vol 15, No. 6, 2019.
Date: November 17, 2019
Photo Credit: The Spokesman Review
Article Link: http://jcsm.aasm.org/ViewAbstract.aspx?pid=31589
So now what do you think? Did it surprise you to see that the significant findings of circadian science relating to the time shift question have clearly NOT been considered by legislators? Is retail spending more important tan mental and physical health? That is NOT a facetious question. Maybe we need to think about the time shift issue a bit more AND have a look at some more data! We clearly need morning light rather badly.
Questions for Discussion:
- Why do most legislators and many people seem to prefer the idea of staying permanently on Daylight Saving rather than Standard Time?
- What is the difference between Social Time (schedules) and Circadian Time (schedules) and why does the difference matter?
- What is your decision about the best was to proceed with regards to time shifting?
References (Read Further):
Watson, Nathaniel F. “Time to show leadership on the daylight saving time debate.” Journal of Clinical Sleep Medicine 15.06 (2019): 815-817. http://jcsm.aasm.org/ViewAbstract.aspx?pid=31589
Facer-Childs, E. R., Campos, B. M., Middleton, B., Skene, D. J., & Bagshaw, A. P. (2019). Circadian phenotype impacts the brain’s resting-state functional connectivity, attentional performance, and sleepiness. Sleep, 42(5), zsz033. https://academic.oup.com/sleep/article/42/5/zsz033/5316210
Kotchen, M. J., & Grant, L. E. (2011). Does daylight saving time save energy? Evidence from a natural experiment in Indiana. Review of Economics and Statistics, 93(4), 1172-1185. https://www.nber.org/papers/w14429.pdf
Kantermann, T., Juda, M., Merrow, M., & Roenneberg, T. (2007). The human circadian clock’s seasonal adjustment is disrupted by daylight saving time. Current Biology, 17(22), 1996-2000.
Carey, R. N., & Sarma, K. M. (2017). Impact of daylight saving time on road traffic collision risk: a systematic review. BMJ open, 7(6), e014319.
Lahti, T. A., Leppämäki, S., Lönnqvist, J., & Partonen, T. (2008). Transitions into and out of daylight saving time compromise sleep and the rest-activity cycles. BMC physiology, 8(1), 3. https://bmcphysiol.biomedcentral.com/articles/10.1186/1472-6793-8-3
Lewis, P., Foster, R. G., & Erren, T. C. (2018). Ticking time bomb? High time for chronobiological research. EMBO reports, 19(5). https://scholar.google.ca/scholar?output=instlink&q=info:wm3-Oe-lWuIJ:scholar.google.com/&hl=en&as_sdt=0,5&scillfp=994473244608805565&oi=lle