St Andrews University students skinny dip in the sea as May Day celebrations in St Andrews, Scotland on April 30, 2017. Hundreds of revellers ditched their clothes and bravely jumped into the bitterly cold North Sea. (Photo by Alamy Stock Photos)

Snow falls as a woman walks her dog in the village of Podolye, 70 kilometers (43 miles) east of St. Petersburg, Russia, early Thursday, May 11, 2017. North winds brought snow to the east of the St. Petersburg region. (Photo by Dmitri Lovetsky/AP Photo)

Uniformed participant dance during a mass rally and parade in the capital's main ceremonial square, a day after the ruling party wrapped up its first congress in 36 years by elevating him to party chairman, in Pyongyang, North Korea, May 10, 2016. (Photo by Damir Sagolj/Reuters)

A woman mourns over the coffin of a relative after a deadly eruption of Mount Sinabung in Sukandebi village, Karo, North Sumatra, Indonesia May 22, 2016, in this photo taken by Antara Foto. The volcano in western Indonesian unleashed hot clouds of ash on Saturday, killing several villagers, an official said. (Photo by Irsan Mulyadi/Reuters/Antara Foto)

Mahouts and their elephants display a poster during a campaign ahead of the August 7 referendum in Auytthaya province, north of Bangkok, Thailand, August 1, 2016. Officials across the country are drumming up campaigns to encourage voting on the draft constitution in a referendum on Sunday. (Photo by Chaiwat Subprasom/Reuters)

Bo, a 55-day-old baby Echidna known as a puggle, rests in the hands of vet nurse Annabelle Sehlmeier at Taronga Zoo in Sydney November 1, 2012. The puggle was brought to the zoo after it being found by itself on a walking track north of Sydney and will be fed by hand until it is weaned at about six months of age. (Photo by Tim Wimborne/Reuters)

A youth in costume hurries past a mural after dancing at the Sun Festival in Cotacachi, Ecuador, Sunday, June 24, 2018. Across the Andes, from the tip of Argentina as far north as Colombia, indigenous communities are gathering for the southern hemisphere's winter solstice to honor the ancient sun god. (Photo by Dolores Ochoa/AP Photo)

After a cold night the small North Devon villages of Appledore and Instow wake up to an amazing scene as the sun rises over the River Torridge estuary, Devon, UK on October 19, 2018. (Photo by Terry Mathews/Alamy Live News)