Visitors watch as Grigory Broverman, a member of the Cryophile winter swimmers club, pours a bucket of cold water over his 6-year-old daughter Liza during a flash mob, part of a celebration of Polar Bear Day at the Royev Ruchey Zoo in a suburb of the Siberian city of Krasnoyarsk, Russia, November 29, 2015. The air temperature was around minus 5 degrees Celsius. (Photo by Ilya Naymushin/Reuters)

People take part in the annual Easter Parade and Bonnet Festival along 5th Avenue in New York City March 27, 2016. The parade, which is more of a stroll than a parade, is more informal than the city's other parades. There are no bands, no floats, and no formations, and anyone can participate. (Photo by Brendan McDermid/Reuters)

A photograph released to Reuters on August 22, 2014 shows the remains of an ancient Mayan city in Lagunita May 30, 2014. Archaeologists have found two ancient Mayan cities hidden in the jungle of southeastern Mexico, and lead researcher Ivan Sprajc, an associate professor at the Research Center of the Slovenian Academy of Sciences and Arts, says he believes there are “dozens” more to be found in the region. (Photo by Reuters/Research Center of the Slovenian Academy of Sciences and Arts)

A dog catches a wave during the Surf City Surf Dog Contest in Huntington Beach, California September 27, 2015. (Photo by Lucy Nicholson/Reuters)

A man salvages his belongings after a raging fire engulfed around 2,000 houses in Quezon city, metro Manila January 1, 2015. At least eight people, including a seven year-old child, died and thousands were displaced after a fire broke out in different locations in metro Manila as the New Year kicked off, local media reported. (Photo by Romeo Ranoco/Reuters)

Tourists and journalists stand next to a newly displayed statue of pharaoh Amenhotep III and his wife Tiye (Down) in Egypt's temple city of Luxor on March 23, 2014. Two colossal statues of pharaoh Amenhotep III were unveiled by archaeologists today in their original sites in the funerary temple of the king, on the west bank of the Nile in Luxor, adding to the existing two famous ancient Memnon colossi. (Photo by Khaled Desouki/AFP Photo)

In this aerial view the officers' building and an auditorium stand at the former Soviet military base on January 26, 2017 in Wuensdorf, Germany. Wuensdorf, once called “The Forbidden City”, was the biggest base for the Soviet armed forces in communist East Germany from 1945 until the last Soviet troops left in the early 1990s following the end of the Cold War and the reunification of Germany. (Photo by Sean Gallup/Getty Images)