The Daily Parker

Politics, Weather, Photography, and the Dog

Semi-annual time-change angst

I'm not going to link to any of the articles published in the last few days about how no one likes changing the clocks to and from Daylight Saving Time. Suffice to say, the debate hinges on two simple questions: how early do you want the sun to set, and how late do you want it to rise, in winter?

For a concrete example, if you live in Chicago, do you want the sun to rise at 7:19 or 8:19 on January 3rd (the latest of the year)? And if the sun rises at 8:19 that morning, is that an acceptable price to pay for the sun setting at 5:20 (instead of 4:20) on December 8th (the earliest of the year)?

A switch to year-long DST would mean that the sun would rise over Lake Michigan after 7am from October 12th until March 17th—five months of morning gloom, offset by the sun never setting before 5pm.

On the western edge of US time zones, the results would be truly weird. Just across Lake Michigan from Chicago is Benton Harbor, Mich. Year-long DST would make the earliest sunset there occur at 6:14pm. But the latest sunrise would be at 9:14am, with the sun rising after 9am from December 7th through January 31st, and the sun rising after 8am from October 17th through March 14th. After 7am? August 22nd through April 19th. Yes, permanent DST would relegate places like Western Michigan, Western Nebraska, and Idaho to nine months of gloomy mornings.

Ultimately I think this is why the permanent-DST proposals will go nowhere in the US. The parts of the US most sensitive to late sunrises (farming areas) will be the ones most affected.

And hey, won't Spain be fun when permanent DST comes to Europe in two years. The sleepy town of Pontevedra, Spain, on the west coast of that country and at about the same latitude as Chicago, will enjoy sunrises at 10:04am in January should Spain go permanently to UTC+2. (But hey, the sun will never set there before 7pm, so maybe that's a good trade-off?)

Of course, this is all about psychology. The sun rises and sets on its own; only our need to agree on time causes these odd artifacts. Maybe in western Spain they'll simply start work at noon? (Or, more likely, switch to UTC+1 year-round.)

Interesting coincidence

The December solstice happens today at 22:21 UTC, which is 16:21 here in Chicago, which it turns out is the exact time of tonight's sunset. This is also true for everywhere along the lightest gray line on this map:

Note also that Africa and Europe will have a brilliant gibbous moon at the same time.

Happy solstice!

California may move to UTC-7 year-round

Governor Jerry Brown approved AB 807, which would put to the voters in November an initiative to go to "year round Daylight Saving Time:"

Wrote Brown in a signing message: "Fiat Lux!" (Let there be light.)

Assemblyman Kansen Chu, D-San Jose, who authored Assembly Bill 807, has called the practice of changing clocks twice a year, in the fall and the spring, "outdated." He argues altering the time by an hour has adverse health affects, increasing chances for heart attacks, workplace injuries and traffic accidents.

The ballot measure would overturn a 1949 voter-approved initiative called the Daylight Savings Time Act, which established Standard Pacific Time in California.

Should voters approve the ballot measure, the Legislature would then decide how the state's time should be set. Congress would have to sign off on Chu's main goal of establishing year-round daylight saving time.

If it passes, L.A. and San Francisco would see sunrises at 7:44 and 8:09, respectively. But sunsets would be 17:44 and 17:51. So...if you live in California, how would you vote?

Changing the clocks

If you live in the parts of the U.S. and Canada that observe Daylight Saving Time, don't forget to move your clocks back an hour tonight. It couldn't come soon enough, though this is the soonest it can come under the 2007 changes to DST observance.

This morning's 7:22 sunrise in Chicago is the latest we'll have to endure until next November 1st, but tonight's 5:47 sunset is the latest we'll get to have until March 6th. Tomorrow the sun rises at 6:23 and sets at 4:45, as our available daylight shrinks from 10 hours, 24 minutes today down to 9 hours, 7 minutes on December 21st.

I'm not a fan of the 2007 changes. I like switching to DST in the spring and switching back in the fall, but I also believe that mid-October (or even the end of September as they do in Europe) makes a lot more sense. At least mornings aren't so gloomy in the fall. (Not a lot we can do about the post-7am sunrises from December 2nd through February 5th, but we expect those two months to be gloomy.)

Of course, I'm not in Chicago at the moment, and it's plenty sunny here...