People look at the Turrialba volcano as it spewes ashes on May 20, 2016, in Cartago, Costa Rica. The Turrialba volcano started erupting columns of smoke and ash that the wind extended towards the Costa Rican capital, in what according to experts is the strongest eruption in the past six years. (Photo by Ezequiel Becerra/AFP Photo)

Female members of the Chinese People's Liberation Army (PLA) honour guard stand behind a string to ensure that they are in a straight line before a welcoming ceremony for Russian President Vladimir Putin outside the Great Hall of the People in Beijing, China, June 25, 2016. (Photo by Kim Kyung-Hoon/Reuters)

A man lies in the sea grass at a beach on July 18, 2016 in Qingdao, Shandong Province of China. The enteromorpha prolifera spread on the beaches in Qingdao and were under clearing. (Photo by VCG/VCG via Getty Images)

Supporters of former Democratic presidential candidate Bernie Sanders hold up posters at a “Black Men For Bernie” rally to gain support for third party candidates and protest the DNC during the 2016 Democratic National Convention on July 27, 2016 in Philadelphia, Pennsylvania. (Photo by Patrick T. Fallon/AFP Photo)

A family pose for a picture as thousands of redheads fill a Dutch city Breda to celebrate International Redhead Day event in Breda, The Netherlands on Sunday, 4 September 2016. Every year natural redheads from more than 80 countries come together at “Roodharigendag” annual weekend long festival to celebrate their ginger genes. The event also holds the world record for the largest number of natural redheads being in one place. (Photo by Akmen/London News Pictures)

Women wearing bikinis and Santa Claus hats participate in a promotional event to celebrate the upcoming Christmas at a ski resort in Xuchang, Henan province, December 23, 2014. Ten women wore Santa Claus-themed bikinis to welcome the coming Christmas in temperatures below zero Celsius. (Photo by Reuters/Stringer)

A man holds a copy of the Koran during a protest against Niger President Mahamadou Issoufou's attendance last week at a Paris rally in support of French satirical weekly Charlie Hebdo, which featured a cartoon of the Prophet Mohammad as the cover of its first edition since an attack by Islamist gunmen, in Niamey January 17, 2015. (Photo by Tagaza Djibo/Reuters)

Relatives of the crashed AirAsia plane passengers pray at Juanda Airport, in Surabaya, Indonesia, 31 December 2014. Indonesian rescuers retrieved three more bodies from the sea on 31 December but the search to recover more victims from the AirAsia plane crash was hampered by bad weather, the recue chief said. AirAsia Indonesia flight QZ8501 crashed into the Java Sea on 28 December, about halfway through a two-hour flight between Surabaya, Indonesia's second largest city, and Singapore. (Photo by Made Nagi/EPA)