Arlington, Virginia - A few years ago, Kevin Bubolz from Virginia was puzzled to discover that his golden retriever Emma's nose suddenly turned pink in winter. What was going on?!

In a TikTok video, Bubolz showed footage of Emma's nose changing color, contrasting it to her sibling Ellie, for whom this isn't the case.

This so-called "snow nose" phenomenon is a regular occurrence, according to the dog owner, but seems to be completely harmless.

Emma's nose simply goes from black, to pink, then back again.

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What is missing is clear explanation of what exactly causes the "snow nose" in dogs.

Even experts are still puzzling over this!

"We’re not sure what causes it, but since it occurs most often in winter or cold weather climates, we think it might have something to do with the temperature or possibly certain enzymes," explained Dr. Sandra Koch, a board-certified veterinary dermatologist, in an interview with petMD.

Unfortunately, however, the expert had to contradict herself a little.

Although the so-called "snow nose" occurs most often in winter, it can also occur in summer or even in tropical areas, she said.

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"We have very limited information on it; there has been little research done, and most of the information we have is anecdotal," Dr. Koch ultimately admitted.

Emma is likely to continue to fascinate her owner with this mystery. Fortunately, Bubolz no longer needs to be worried about his pup's "mood ring" of a nose!