White Christmas

A white Christmas is a Christmas with the presence of snow, either on Christmas Eve or on Christmas Day, depending on local tradition. This phenomenon is most common in the northern countries of the Northern Hemisphere. Because December is at the beginning of the Southern Hemisphere summer, white Christmases there are extremely rare, except in Antarctica (uninhabited), in the Southern Alps of New Zealand's South Island, and in parts of the Andes in South America as well as the southern tip of the continent, in places like Ushuaia, Argentina. The opposite of a white Christmas, when there is no snow and thus the ground is bare, is traditionally known as a "green Christmas," from the color of bare grass. The notion of "white Christmas" was popularized by writings of Charles Dickens. The depiction of snow-covered Christmas season found in The Pickwick Papers (1836), A Christmas Carol (1843), and his short stories was apparently influenced by memories of his childhood, which coincided with the coldest decade in England in more than a century. The song, "White Christmas", written by Irving Berlin and sung by Bing Crosby (with the Ken Darby singers and John Scott Trotter and his orchestra) and featured in the 1942 Paramount Pictures film Holiday Inn, is the best-selling single of all time and speaks nostalgically of a traditional white Christmas and has since become a seasonal standard. Definition The criteria for a "white Christmas" varies. In most countries, it simply means that the ground is covered by snow at Christmas, but some countries have more strict definitions. In the United States, the official definition of a white Christmas is that there has to be a snow depth of at least on the ground on 25 December in the contiguous United States, and in Canada the official definition is that there has to be more than on the ground on Christmas Day. In the United Kingdom, although for many a white Christmas simply means a complete covering of snow on Christmas Day, the official definition by the British Met Office and British bookmakers is for snow to be observed falling, however little (even if it melts before it reaches the ground), in the 24 hours of 25 December. Consequently, according to the Met Office and British bookmakers, even of snow on the ground at Christmas, because of a heavy snow fall a few days before, will not constitute a white Christmas, but a few snowflakes mixed with rain will, even if they never reach the ground.