On Tuesday, the US Senate voted unanimously to pass the Sunshine Protection Act, legislation that would keep the United States on Daylight Saving Time, also known as Daylight Time, what we are on from mid-March to early November. The Senate’s action on Tuesday sends the legislation to the House of Representatives, where if it passes, it will arrive on the desk of President Biden. If it clears all these hurdles, it will be implemented in November 2023, meaning there will be no "fall-back" on November 5, 2023.
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| The sun sets over the Pacific Ocean at 4:40 PM on December 31, 2021, viewed from Oysterville, WA. Under the Sunshine Protection Act, this sunset would occur at 5:40 PM. Now that this legislation has unanimously passed the Senate (a rare feat these days), it has a decent possibility of passing the House and being signed by the President. So…what does the potential implementation of the Sunshine Protection Act mean for the Pacific Northwest? A summary would be later sunrises and later sunsets from early November to mid-March, as we remain on Pacific Daylight Time. Essentially, the time that is currently “Pacific Standard Time” will be when you notice the biggest changes. The Pacific and Mountain Time Zones would be most impacted with late sunrises. For reference, Pacific is orange and Mountain is green. (Map found here)  A bit of background...under the Uniform Time Act of 1966, states can opt out of the current Daylight Saving Time structure (like Arizona and Hawaii) but states cannot switch to permanent Daylight Saving Time without Congressional approval. The passage of the Sunshine Protection Act would be that approval for all 50 states. |
Let’s go in-depth on the impacts of this legislation in the Pacific Northwest. Below is a graphic from my personal weather station showing solar radiation on each day of December 2021.
December has the least solar radiation of any month of the year, only peaking around 400 watts/meter^2 (In comparison, June and July peak at 1,200-1,500 w/m^2).
There is a red box around December 13th, 2021, the darkest day of the month. The solar radiation graph for the 13th is below.
Solar radiation only peaked at 68.8 w/m^2. This would be considered quite a "dark" day by normal standards, but it will seem even darker under the Sunshine Protection Act.
Under 2021 time rules, the sun rose at 7:49 AM and set at 4:17 PM, one of the shortest days of the year (at 8 hr, 28 min).
Under the proposed Sunshine Protection Act, the sun would rise at 8:49 AM and set at 5:17 PM. This means that a normally dark day would seem much darker, with the sun not rising until around 9 AM. A sunrise around 9 AM combined with a very dark day wouldn’t bode well for many people in the Northwest, especially the population impacted by Seasonal Affective Disorder (SAD).
Under the Sunshine Protection Act, sunrises after 8:30 AM would occur from approximately November 26th to February 4th. The benefit of this would be winter sunsets one hour later, eliminating sunsets before 5:15 PM.
Also...time from March to November (most of spring & summer, part of fall) would be unchanged, meaning that about 9 months out of the year will experience no changes.
The graphic below from a 2019 Cliff Mass Weather Blog post shows solar radiation in Seattle in 2019.
The parts of the year that will be most impacted by the Sunshine Protection Act happen to have the least amount of sun (November through mid-March). Due to the Pacific Northwest’s position at a northern latitude, sunlight is a topic of significant discussion. Opposition to switching to permanent Daylight Saving Time is stronger here than in most of the country. An informative article from The Seattle Times is linked below.
The Sunshine Protection Act is an interesting possibility that will mainly have impacts during late fall and winter. Stay tuned for more information, should the legislation advance.
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