The physics of falling back: why Mid-Missouri is losing its evening light
If your drive home from work feels like it is about to get a lot darker, you aren't imagining things. Daylight Saving Time officially comes to an end at 2:00 A.M. this Sunday, November 1st. While gaining an extra hour of sleep over the weekend is always a welcome treat, the trade-off is a jarring shift for our evening commutes, plunging our sunsets straight back into the five o'clock hour.
But why does it feel like we lose so much light all at once? The answer lies in a mix of planetary physics and timekeeping.
The natural loss of daylight we experience throughout the fall is entirely driven by the geometry of our solar system. The Earth does not sit perfectly straight up and down; it rests on a 23.5-degree axis. Right now, as our planet travels along its orbit toward the Winter Solstice in late December, the Northern Hemisphere is actively tilting away from the Sun.
Because we are leaning away from our star, the incoming solar radiation strikes Mid-Missouri at a shallower angle, and the Sun spends less time above our horizon. We are actively losing a few minutes of total daylight every single day.
When we look at the forecast data for Columbia this weekend, the impact of the time change becomes clear. On Saturday, October 31, the Sun will set at approximately 6:09 P.M. On Sunday, November 1, the Sun will set at 5:07 P.M.
It feels like we are losing an entire hour of daylight overnight, but that is just the illusion of the clock change. In reality, Mother Nature is only taking away four minutes of total daylight this weekend. On Saturday, Columbia will see 10 hours and 34 minutes of total daylight. On Sunday, that number only drops to 10 hours and 30 minutes. The abrupt plunge into evening darkness is entirely man-made.
This shift often sparks the same question every year: why don't we just keep Daylight Saving Time year-round?
When we "fall back" in November, we are actually returning to Standard Time. Daylight Saving Time was implemented to maximize summer evening sunlight and conserve energy. However, if we kept the clocks pushed forward through the dead of winter, our mornings would be dangerously dark. In Mid-Missouri, a year-round Daylight Saving Time would mean the sun wouldn't rise until nearly 8:30 A.M> in late December and January. This would leave children waiting for school buses and morning commuters navigating slick roads in pitch darkness.
Before you head to bed this Saturday night, remember to manually set any analog clocks, microwaves, and ovens back one hour. The end of Daylight Saving Time is also the perfect, easy-to-remember milestone to swap out the batteries in your home's smoke and carbon monoxide detectors, as well as the batteries in your NOAA weather radios.
