The Shadow Knows

Who knows how much longer the winter will last?

The Shadow knows.

Okay, so that’s not exactly how those old radio serials used to begin.  However, the idea of all-knowing shadows brings to mind a strange weather forecast that will take place in a few weeks.

Wuchak
Creative Commons License photo credit: Furryscaly

Early next month, a large rodent will emerge and look at the ground. If he sees his shadow, he scurries back into his winter den, and it is said that winter will continue for six more weeks. If there is no shadow, he stays out, and an early spring is in the offing. But, how does the groundhog’s shadow let us know how long the winter will be?

Understanding this forecast begins with knowing the cycle of the seasons.  The Earth orbits the sun with its axis tilted by about 23.5 degrees.  On about June 21 each year, the North Pole is tilted as much as possible towards the sun and the sun takes its highest path across our sky.  This is the summer solstice for us and the winter solstice for the Southern Hemisphere.  Six months later, the South Pole is tilted as much as possible towards the sun and the sun takes its lowest path across our sky.  Dec. 21 is our winter solstice and the summer solstice below the equator.  Halfway between these dates, on about March 20 and September 22, the sun is overhead at the equator and both poles are on the day-night terminator.  As everyone then has the same amount of daylight and nighttime, these dates are the equinoxes.  We can think of the solstices and equinoxes as ‘quarter days.’

We have come to define our seasons as beginning at the solstices and equinoxes.  Northern European pagans, however, paid equal if not more attention to dates about halfway between the solstices and equinoxes, called the ‘cross-quarter days.’  For them, seasons began at the cross-quarter days, while the solstices and equinoxes were the midpoints of the seasons.  A while ago, I blogged about the cross-quarter day between the fall equinox and the winter solstice, Samhain, and explained how its traditions influenced our Halloween celebrations.  Now, as January ends and February begins, we are approaching the halfway point between the winter solstice and the spring equinox–another cross-quarter day.

For the Celts, this was Imbolc (pronounced as if there were no ‘b’), sacred to Brigid, goddess of fine craftsmanship, healing, poetry and generally anything involving the higher faculties of mankind, as the Celts understood them.  Among the traditions associated with Imbolc was the belief that Brigid’s snake would emerge from its winter resting place and test the weather.  Germans used a hedgehog to forecast the weather.  If the animal in question scurried back into its burrow, it was a sign that much more winter was ahead.

8981 - St Petersburg - Hermitage - Gaius Julius Caesar
Creative Commons License photo credit: thisisbossi

In the time before the Celts encountered the solar calendar established by Julius Caesar, the actual date of Imbolc varied from year to year.  With the adoption of the Romans’ calendar, Imbolc came to be observed on Feb. 1 (just as observations of Samhain moved to Nov. 1 and the eve of that day).  The actual midpoint between the winter solstice and the vernal equinox is Feb. 3.

Feb. 2 is Candlemas Day, the 40th day of Christmas (with Christmas as day 1).  Christians observe this as the presentation of the baby Jesus at the temple.  As has often occurred when Christian observances nearly coincide with pagan ones, folklore from one became attached to the other.  Thus, as northern Europeans began to migrate to America, they had a weather forecast descended from Imbolc associated with Feb. 2.  Upon arriving here, they replaced the hedgehog (not native to America) with a uniquely American animal, the groundhog.

Light and Dark
Creative Commons License photo credit: ZeroOne

Let’s look more closely at the rules for the Groundhog Day forecast.  If we don’t want the groundhog to see his shadow on Feb. 2, then we must not want sunshine that day.  Good weather (bright and sunny) is a bad omen, while bad weather is a good omen.  This page quotes some sayings from Europe and America which make this explicit.  To appreciate this apparent reverse psychology, let’s consider another day on which bad weather is welcome: Christmas.

Think back to early last month, when Houston experienced a snowfall on Dec. 4 (it had never snowed that early in the winter here in Houston).  Think back even further to our Christmas Eve snowfall in 2004 (our first white Christmas ever).  Such unusual weather (for us) reminded many of favorite holiday songs such as ‘Let it Snow’ or ‘White Christmas.’  “Now this feels like Christmas,” many told themselves.  Now recall the bitter cold a few weeks ago this January.  Did anyone break into song?  Was anyone saying, “At least this feels more like January?”  Why the double standard?  Why is the type of weather we welcome at Christmas just bad weather when it happens in January?

It seems that people who made their living off the land and thus depended on regular seasonal changes constantly looked for reassurance that the natural cycles were functioning properly.  A winter that was truly wintry was therefore a good omen.  If winter happened when it should, then perhaps spring, summer, and the harvest would occur in their proper times, and everything was in balance.  If winter were warm and sunny, however, then something was wrong.  If winter was not happening in its season, then other seasons might also fail to appear.  In particular, people feared that failing to have a true winter at the proper time would require ‘remedial’ winter during springtime.

In time, the winter solstice and the cross-quarter day, Imbolc (later Christmas and Candlemas Day) came to stand in for the whole winter.  Thus, wintry weather on Christmas and on Feb. 2 is a good omen, while bright, sunny weather on these days is a bad omen.  And so, the sight of his shadow frightens the groundhog back into his burrow.

Into the sun
Creative Commons License photo credit: James Jordan

The winter of 2009-2010 has been more severe than usual, not just in Houston but across much of the Northern Hemisphere.  Thus, many can sympathize with those who are looking for any possible sign of spring.  As it turns out, there is a sign of approaching spring that becomes noticeable as February begins–the greater height of the sun.

Ever since the winter solstice, we have seen the sun take a slightly higher path across our skies each day.  However, the difference in height is difficult to notice until February.  This is because the height of the sun during the year varies like a sine wave.  There is little variation near the maximum and minimum; most of the change occurs midway between these points.  During February, March and April, the sun’s higher path is more apparent than in January. All shadows, including those of groundhogs, get noticeably shorter each week.  If you can’t measure shadows during the day, try observing the same change in the position of sunset.  From the same vantage point, notice where the sun sets once each week during February, March and April.  You’ll notice a distinct shift towards the north (towards the right as you face sunset in the west) with each observation.  Since this happens every year as winter turns to spring, you now have reliable assurance that spring is on the way.  No need to be afraid of shadows.