Solar spring is here, and that means we are gaining more daylight in an increasingly big way

Sunrise on Saturday, Feb. 5, in Dover, Mass.

Welcome to solar spring! You may not have heard of this happy astronomical marker but Saturday marks the end of the darkest quarter of the year and the beginning of the greatest three months of light gain we experience all year.

Solar spring is the first of three spring markers and in my opinion one of the best. Light is so critical and when we have more of it, lots of things change.

The gap between sunrise and sunset is now back to what it was on Nov. 5 with 10 hours and 10 minutes of possible sunshine. Between now and May 5 we will gain a whopping 4 hours and 4 minutes more light. All of this increase in solar radiation will be a signal for plants to start growing and animals to start becoming more active and mating. In general for nature, spring is underway.


Of course, we can still have below-zero weather, major snow storms, and it’s unlikely you’re going to the beach this weekend, but solar spring is a real thing. Next up on the calendar will be meteorological spring, which begins March 1. That marks the end of the coldest quarter of the year and starts the transition, into the warmest which is of course meteorological summer.

Astronomical spring arrives at 11:33 a.m. on Sunday, March 20, and this is probably the spring you were taught as a kid. That’s the point that the sun rises at the top of the planet and sets at the bottom and also marks when nearly everywhere has about 12 hours of darkness and 12 hours of daylight.

May 5 through Aug. 5 is solar summer. When this begins we have 14 hours and 14 minutes of daylight but only increase an hour and 3 minutes peaking on June 21 with 15 hours and 17 minutes of daylight. From there Boston stays above 14 hours and 14 minutes between sunrise and sunset until August 5, when the loss of daylight starts to really become noticeable and increases rather quickly.

Daylight is so important to our mood, and whether you just don’t like the winter darkness or have suffered through a long bout of seasonal affective disorder, it’s time to open the shades and let the sun shine in.



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