Groundhogs, Shadows and Growing Light

+ Von Del Chamberlain +

All things around us change constantly, especially the apparent relationships between what we experience on Earth and what we can observe in the sky. The Sun appears to move and everything on Earth responds. Today we know full well that it is Earth cruising in its orbit that causes seasons, but for centuries it had appeared to earthbound observers that it was the Sun moving in a cycle to increase and decrease its light throughout the year.

The most highly publicized dates to celebrate this oscillating light-of-life are the times when the Sun appears to turn on the horizon in its rising and setting points, the summer and winter solstices. In between these are the autumn and spring equinoxes when day lengths are most rapidly changing. Less frequently noted, yet just as interesting, are the mid-way points between solstices and equinoxes, the so called "cross-quarter" dates. As far as the factors that produce weather are concerned, these are times when climatic changes are most pronounced. One of these transitional dates is approaching now. It has an interesting history, starting with astronomy and ending with what many consider to be a lowly creature that spends much of its time underground, but once each year becomes a symbol of the celebration of growing light with the approach of spring.

We have seen in earlier issues of this column that in much of Europe the summer solstice is referred to as mid-summer and the winter solstice as mid- winter. Indeed, these extremes in Earth-Sun relationships, when we have longest and shortest days and when, in the northern hemisphere, the Sun's energy is greatest on the one hand and least on the other, are the central times for solar radiation effects that relate to seasons. With this line of thinking, the start of autumn would be the mid-way time between summer solstice and autumnal equinox, currently persisting as Halloween. In this same vane, the start of springtime weather would be the cross-quarter date between winter solstice and vernal equinox, Groundhog Day. Here is how this cross-quarter day has come down to us.

The Celts once celebrated it as Imbolg, honoring Brigit, the Earth Mother. Imbolg referred to "ewe's milk" in the lambing season, signaling spring and Brigit was god of fire and fertility for the Celts, but later Christians dedicated the day to Saint Brigit, patron of cattle and dairy farming. Legend says that Saint Brigit was born at sunrise on the threshold, neither inside nor outside of the house. Thus, she represents the transition to spring. She nursed on milk from a supernatural cow, dried her dresses on a clothesline of sunbeams and everything around her glowed as if on fire.

This same cross-quarter date was celebrated in Scotland as Candlemas, the legendary day when Christ was first presented in the temple. It was said that Candlemas was the time when the weather pattern for the remainder of the year would be apparent:

Thus, people watched the weather on Candlemas to judge how the rest of the year would go. If Candlemas was clear, it signaled to those who clung to this tradition that foul weather was ahead, but if it was cloudy, then one could expect conditions to improve.

This contrary theory of weather predicting became associated with hibernating animals, such as bears and hedgehogs, coming out of the ground to see if they cast shadows. Thus, in America, the Irish Imbolg, Saint Brigit's Day and the Scottish Candlemas were transformed into Groundhog Day. Like Candlemas, if the weather is clear, allowing the Groundhog, as he comes out of hibernation on this mythical day, to see his shadow, it is said to signal persisting winter and late spring. If, on the other hand, the day is clouded and no shadow appears, the weather ahead should be warm with early spring. Some weather prophets suggest a basis for this: that clear weather in early February usually results from cold, clear stable air masses which are likely to persist in repeated patterns with the result of sustained cold temperatures.

Everything around us seems to inaugurate beauty as we enter the month of February. The stars at eventide are stunning: Canis Major, with Sirius, brightest star in the night; Orion has ruddy Betelgeuse, white Rigel, the three jewels of the belt, and the nebulous sword; two gem-star clusters, Pleiades and Hyades, bedeck the constellation Taurus, along with the pale rose star Aldebaron; Auriga has the sun-yellow star Capella; and the Twins of Gemini remind us of old stories of argonauts and recent ones of astronauts. These are the brightest and most colorful stars in all the heavens, forming some of the easiest patterns to learn. Look high to the south as darkness comes and you will see them. If you need a little help, visit Hansen Planetarium for the program, "Jewels of a Winter Night," and pick up free star charts available in the lobby.

What is most worth applauding this time of year is the combination of factors causing weather change to be so apparent. We have made it through the short dreary days of winter and light lingers longer with each new day. It is easier to get up earlier and go more cheerfully to work, school or play. In our part of the world, light is increasing, promising warmth, north-flying flocks, sprouts springing from wet ground, and feelings of joy being out under the sky, both day and night. Judged by the rapidly changing conditions, Groundhog Day can well be thought of as the beginning of spring. A time of diminishing shadows. A time for celebrating light!

This article was modified from the original to serve as an information source for all Groundhog Day cross-quarter events.

Another good article to read is Phil Plait's What Causes the Seasons?

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