It was 25 December, and little George Adamson ran to the window, hoping to find a white world on the other side. But once he drew the curtains, disappointment set in. It was another year without snow on Christmas Day.

Now, as a geography lecturer at King’s College London, he knows who to blame for his misplaced expectations: Charles Dickens, who populated his stories with snowy depictions of the holiday period. 

That people like him imagine a snow-covered Christmas has always intrigued Adamson. In the UK, where he grew up, December is not a particularly snowy month – yet shops sell cards with white Christmas illustrations and restaurants decorate with fake snow. Where are people taking on these expectations if they haven’t lived them?

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Scholars believe that it comes from cultural messaging. And crucially, from the very frosty decade of 1810.

In turn, the prominence of Dickens’ writings permeated our imagination.

Dickens “grew up during the coldest decade England has seen since the 1690s and his short stories and A Christmas Carol seem to owe much to his impressionable years”, writes anthropologist Brian Fagan in his book The Little Ice Age.  

It was so icy during Dickens’s early years that the River Thames froze in February of 1814. London celebrated its final Thames frost fair that year, which included people setting up tents on the ice for four days and an elephant being led across the river just below Blackfriars Bridge. For the young Dickens, who was born in 1812, Christmas must have been a bitterly cold experience.

Years later, when Dickens sat down to write his novels and short stories, the author populated them with his memories of what Christmas looked like back then.

Christmas myth

But that doesn’t mean a ‘white Christmas’ has been common in the decades since.

While it might seem self-evident, the definition of a white Christmas is contentious – so measuring how often it’s happened is surprisingly complicated. The criteria that the UK’s Met Office uses to define a White Christmas is for one snowflake to be observed falling in the 24 hours of 25 December somewhere in the UK. By that definition, the phenomenon is not so rare – it has occurred more than 30 times in the past five decades. But go explain that criteria to a little girl looking out the window on Christmas Day.

“If that [situation of one snowflake falling] happens, no one would say there is a white Christmas,” Adamson says, although as a climate expert he understands the Met Office must have an official definition.

BBC Future asked the Met Office for more information about Christmas snow in the UK, as tracked by their more than 200 stations across the country.

Our suspicions were correct. The country being blanketed in snow – as in 1982 when 260 different locations reported snow on the ground – is atypical. Most years, no more than 20 stations report snow. In the UK, the UK Met Office explains, it is far more likely to see snow between January and March than in December.

So if it hasn’t been accurate in the UK for some time, why do we still mentally picture a snowy Christmas? And how can one man’s writing alter our collective understanding of a climatic phenomenon?

It helps that Dickens is credited, particularly in Britain, as the man who made Christmas fashionable again.

As the Industrial Age set in and people moved around the country, traditions were diluted and customs were lost. In the first decades of the 1800s, both Sir Walter Scott and Washington Irving lamented the loss of former festivities.

When Dickens published A Christmas Carol in 1843, Victorian Britain clung to its depiction of the idyllic holiday season, as many middle-aged Britons looked back nostalgically to the Christmas of their youth.

“In view of the fact that Dickens can be said to have almost singlehandedly created the modern idea of Christmas,” writes Dickens biographer Peter Ackroyd, “it is interesting to note that in fact during the first eight years of his life there was a White Christmas every year; so sometimes reality does actually exist before the idealised image.”

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Diego Arguedas Ortiz is a science and climate change reporter for BBC Future. He is @arguedasortiz on Twitter.

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