Revelers celebrate during fireworks marking the start of the New Year on Copacabana beach on January 1, 2017 in Rio de Janeiro, Brazil. Brazilian revelers traditionally dress in white to honor the New Year's holiday along with the Brazilian Goddess of the Sea- Iemanja. (Photo by Mario Tama/Getty Images)

Disguised revellers parade on the occasion of the Cortege during the Carnival in Basel, Switzerland, February 17, 2016. (Photo by Georgios Kefalas/EPA)

A 40-foot sculpture of the swimmer Rebecca Adlington was unveiled at the Serpentine in London’s Hyde Park on July 25, 2016 to launch a campaign by Kelloggs to encourage the public to support Team GB at the Rio Olympics. (Photo by David Parry/PA Wire/Barcroft Images)

Principle Ballet Dancer, Ekaterina Bulgutova, of the Russian State Ballet, with the Nutcracker part of Christmas Ballet Season in Cardiff which starts at St Davids Hall on December 20, 2016 in Cardiff, England. (Photo by Kiran Ridley/Barcroft Images)

These adrenaline-junkie climbers go to extraordinary lengths, and heights, to take a selfie. Hundreds of metres above the ground, the climbers risk their life and liberty as they scale huge structures and photograph the results. Known as urban exploration, the aim is to find extremely high and almost inaccessible city buildings and reach their dizzying summits. (Photo by Yaroslav Segeda/Solent News)

In this April 23, 2015 photo, friends Jia Haixia, left, and Jia Wenqi work to plant a tree in a field in Yeli village near Shijiazhuang city in northern China's Hebei province. For the past 13 years, Jia Wenqi, who has no arms, and Jia Haixia, who is blind, have worked together to plant and water more than 12,000 trees near their village. (Photo by Helene Franchineau/AP Photo)

Ukrainian President Petro Poroshenko gestures during a news conference in Kiev, Ukraine, June 5, 2015. REUTERS/Mykhailo Markiv/Ukrainian Presidential Press Service/Pool

In this May 14, 2016 photo, children wearing their school backpacks climb on a cliff using a bamboo ladder on their way home from school in Zhaojue county, southwest China's Sichuan province. A village in China's mountainous west where schoolchildren must climb an 800-meter (2,625-foot)-high bamboo ladder secured to a sheer cliff face may get a set of steel stairs to improve it's safety. (Photo by Chinatopix via AP Photo)