A guard dog in the suburbs of Yakutsk, Russia, considered to be the coldest city in the world, January 2014. (Photo by Amos Chapple/REX Features)

Hannah Maule-ffinch, “Wild Swimmers”, 2020, Hinksey Lake, Oxfordshire. Category: People. The series Wild Swimmers explores how humans are strongest when coming together in the face of adversity. In this photo, Emma and Emma have an amazing bond and friendship, built through their daily ritual of cold swimming in often bracing conditions. (Photo by Hannah Maule-ffinch/Earth Photo 2022)

Performers of Everland Amusement Park present the part of Christmas Fantasy in downtown of Myundong in Seoul, South Korea on December 3, 2019. (Photo by Seokyong Lee/Penta Press/Rex Features/Shutterstock)

Pedestrians wear masks as smoke and haze from bushfires in New South Wales blankets the CBD in Sydney, Australia, 10 December 2019. The New South Wales environment department says visibility across east and southwest Sydney was at a “hazardous” level on Tuesday morning, while air quality was poor in southwest Sydney and hazardous in northwest Sydney. (Photo by Steven Saphore/EPA/EFE)

This handout picture taken and released by Thai Royal Household Bureau on December 12, 2019 shows Thailand's Princess Bajrakitiyabha (L) and Princess Sirivannavari sit in their barge during the Royal Barge procession in Bangkok. The Royal barge procession is the final event of the coronation of Thailand’s King Maha Vajiralongkorn. (Photo by Thai Royal Household Bureau via AFP Photo/Handout)

Female activists perform a choreography originated in Chile, and inspired by the Chilean feminist group Las Tesis, to protest against gender violence and patriarchy in front of the Greek parliament at Athens' Syntagma Square on December 22, 2019. (Photo by Louisa Gouliamaki/AFP Photo)

Swimmers take part in the annual Christmas Day swim in Porthcawl, Wales, England on December 25, 2019. (Photo by Ben Birchall/PA Images via Getty Images)

Winter swimmers dressed in ballet costumes pose for a photo before diving into the icy water, during a snowfall at a park in Shenyang, Liaoning province, China on February 15, 2019. (Photo by Reuters/China Stringer Network)