Dreaming of a white Christmas

Richard Collins explains why there won’t be any more snow days in Ireland.

LIKE Bing Crosbie, we dream of white Christmases. However, the idea that the country should be blanketed in snow, to be properly decked out for the festival, is somewhat odd. Christmases are hardly ever white at our latitude, at least in Europe. Most places in Ireland, I am told, had snow on Christmas day in 1947, exactly sixty years ago but the festive landscape has remained green every year since then. Yet, the pictures appearing on Christmas cards always have snowy backgrounds and it’s de rigeur for film-sets to be decked out in cotton wool when Christmas scenes are being shot.

So what has given rise to this curious meteorological expectation? Is it an ancient folk memory, handed down through the generations, or the Little Ice Age which hit Europe several centuries ago? During the 1500s, Europe began to experience more severe winters. Nobody is sure why but fluctuations in the output of the sun or the long-term effects of volcanic eruptions may be responsible. Paintings from those times depict skaters on Dutch canals and hunting parties setting out into gleaming white landscapes. The very cold winters lasted well into the 19th Century; in Dickens’ day, the Thames froze over regularly. We occasionally get a taste of Little Ice Age conditions here; many of Ireland’s rivers became ice-bound in 1963 and again in 1982.

Now, with the onset of global warming, we can put aside any lingering hopes we shared with the late Bing Crosby. We still get some snow in January or February most years, but soon even that may be just a memory. The possibility that climate change will alter the flow of the Gulf Stream, as some scientists have predicted, can’t be ruled out. If the great flow of tropical Atlantic water, which keeps Western Europe snug, is forced downward under the lighter freshwater of melted Arctic ice, there will be plenty of snow here at Christmas. The prettiness of the landscape, however, will be the least of our worries; without the comfort of warm seas, Ireland’s climate will resemble that of the Canadian sub-Arctic.

Every cloud has a silver lining; our heating bills should be lower in the warmer winters and we won’t need such heavy clothing. There are fashion implications for animals also; humans are not the only creatures to don new outfits for the winter. When it comes to couture, Irish mammals and birds are likely to become trend-setters. Mountain hares throughout Europe, including those in Scotland, turn white at this time of year but Irish hares remain brown. A white pelage helps to camouflage a hare against a snowy background.

In a warmed-up snow-free Europe, hares decked out in traditional white outfits will lose out. To reduce the risk from predators, they will have to adopt Irish fashions and wear brown coats. Of course, a hare can’t change its fur at will; natural selection will bring about the change over many generations. There will also be some additional costs for the animal. Hair is naturally white and no colour need be added to a white winter coat. Changing to a brown one will require pigments and additional food resources will be needed to generate them.

European stoats, too, will have to put their white outfits away and, like our Irish ones, stay brown for the winter. This won’t be welcome news for another declining species; royalty. Ermine, the white winter fur of the stoat, is used to make royal robes and hats. In a warmed-up Europe there won’t be white stoats; the crowned heads, if there any left, will be forced to make do with brown fur. White coats are less common among Irish birds. Our red grouse stays brown for Christmas, unlike his European equivalent, the willow grouse, who wears white throughout the winter. Although Irish and Scottish birds have a separate name, they belong to the same species as the willow. Only one Irish bird wears a white winter coat; the snow bunting, little flocks of which, from Scotland and Scandinavia, turn up along our coasts.