A tourist walks inside the Ice Palace glacier hollow at Hintertux glacier, located at around 3250 meters above sea level, in Zillertal, Austria, 02 March, 2016. The hollow's temperature remains constant at 0 degrees Celsius, in summer and winter alike, and is also used by the University of Innsbruck for scientific research projects. (Photo by Lisi Niesner/EPA)

Residents watch the forest burn in Portezuelo, Chile, Sunday, January 29, 2017. Chilean President Michelle Bachelet has announced that the country will continue with its various measures to deal with wild fires, one of the biggest natural disasters in the country for decades, according to a government report released on Sunday. (Photo by Esteban Felix/AP Photo)

Residents of the Brussels suburb of Molenbeek are searched by police before taking part in a memorial gathering to honour the victims of the recent deadly Paris attacks, in Brussels, Belgium, November 18, 2015. (Photo by Yves Herman/Reuters)

Nick Franklin, in action during the FMX competition at the 23rd edition of Free4Style this Saturday, July 2, 2016 in Estavayer-le-Lac,Switzerland. (Photo by Jean-Christophe Bott/Keystone/APA)

Fans of Germany react as they watch the Euro 2016 match between France and Germany in France at a public screening of the match in Berlin, Germany, July 7, 2016. France won 2-0. (Photo by Hannibal Hanschke/Reuters)

More than 400 people stripped off and ran into freezing waters to celebrate the autumn equinox – and raise money for charity at Druridge Bay, Britain, September 25, 2016. It was the largest turnout the North East Skinny Dip has ever seen in its five-year history, and it was also the first time it has ever rained on the morning of the event. Revellers gathered from 5.30am on Sunday at Druridge Bay, in Northumberland, before baring all in the North Sea. (Photo by David Charlton Photography)

In this October 5, 2016 photo a man looks at the work “Not to be Reproduced” by Rene Magritte at the Kunsthalle art gallery in Hamburg, Germany. The exhibition, which runs from Oct. 7, 2016 until Jan. 22, 2017, features more than 150 masterpieces of surrealism from four of the most significant European private collections of the 20th century. (Photo by Daniel Reinhardt/DPA via AP Photo)

People clash with Venezuelan National Guards as they try to cross the border to Colombia over the Francisco de Paula Santander international bridge in Urena, Venezuela December 18, 2016. (Photo by Carlos Eduardo Ramirez/Reuters)