Tourists view Hukou Waterfall on the Yellow River in the frigid winter on December 28, 2023 in Yan'an, Shaanxi Province of China. Freezing winter air has turned Hukou Waterfall into an icy wonderland. (Photo by VCG/VCG via Getty Images)

The Royal Castle is seen a veil of heavy winter smog in Budapest, Hungary on January 30, 2017. (Photo by Laszlo Balogh/Reuters)

A donkey savors warming temperatures after a long winter at the zoo in Warsaw, Poland, on Wednesday, April 8, 2015. (Photo by Czarek Sokolowski/AP Photo)

A woman yawns as she sits outside a hospital on a cold winter morning in Srinagar January 3, 2019. (Photo by Danish Ismail/Reuters)

Goats covered with cloth are tied next to a hut on a cold winter morning in New Delhi on December 26, 2023. (Photo by Arun Sankar/AFP Photo)

A woman sits behind a bicycle on a cold winter morning in New Delhi, December 31, 2019. (Photo by Anushree Fadnavis/Reuters)

National Geographic photographer Steve Winter has spent most of his adult life shooting wild cats. Photo: A 14-month-old cub, cooling off in a pond, is riveted by a deer that appeared near the shore. Tigers are powerful swimmers; they can easily cross rivers four to five miles wide and have been known to swim distances of up to 18 miles. (Photo by Steve Winter/National Geographic)

In this Friday, February 6, 2015 photo, sandhill cranes begin to stir after resting for the night at a roosting location along their winter migration route in Cecilia, Ky. According to counts made by biologists with the Kentucky Fish and Wildlife Resources, about 12,000 of the birds have stopped in Cecilia this week during their winter northward migration on their way to their nesting grounds in the Great Lakes region. (Photo by David Stephenson/AP Photo)