Internally displaced Syrians who fled Raqqa tie ropes for their tents in a camp in Manbij, Syria on April 6, 2017. (Photo by Rodi Said/Reuters)

A Lebanese man wears a mask to protect himself from the dust as a sandstorm blows over the northern Lebanese city of Tripoli on September 8, 2015. An unseasonal sandstorm has hit the Middle East, reducing visibility and sending dozens to hospitals with breathing difficulties. (Photo by Ibrahim Chalhoub/AFP Photo)

Workers from the South Florida Science Center and Aquarium and Imagine Exhibitions put together an animatronic spinosaurus outside the science center in West Palm Beach, Fla., Tuesday, October 27, 2015. The giant spinosaurus is part of the Dinosaurs Around the World exhibit, set to open on November 1. (Photo by Maria Lorenzino/South Florida Sun-Sentinel via AP Photo)

A child looks at window cleaners work while dressed in sheep (C) and monkey costumes, denoting animal signs of the Chinese zodiac calendar, during an event marking the upcoming end of the year at a hotel in Tokyo, Japan, December 21, 2015. According to the zodiac calendar, 2015 is the year of the sheep and 2016 is the year of the monkey. (Photo by Thomas Peter/Reuters)

Toyota driver Rainer Wissmans of Germany drives during the 2nd stage of the Dakar Rally 2015, from Villa Carlos Paz to San Juan January 5, 2015. (Photo by Jean-Paul Pelissier/Reuters)

A handout picture provided by Solar Impulse on 18 March 2015 shows the Swiss solar-powered plane Solar Impulse 2, HB-SIB, taking off with Swiss explorer Andre Borshberg on board for the third leg Ahmedabad to Varanasi, of the Round-The-World, in Ahmedabad, India, 18 March 2015. Swiss explorers Bertrand Piccard and Andre Borschberg attempt to circumnavigate the world flying with an aircraft, with a 72 metres wingspan, powered only by solar energy without a drop of fuel. (Photo by EPA/Solar Impulse)

Hundreds of Nigerians celebrate at an intersection in the flashpoint northern city of Kaduna on March 31, 2015 the victory of main opposition All Progressives Congress (APC) presidential candidate Mohammadu Buhari. (Photo by Nichole Sobecki/AFP Photo)

Tourists pose with pigeons in the flooded St. Mark's Square in Venice, on November 7, 2014. The high water, a combination of high tides and a strong Scirocco wind in the Adriatic Sea, stood at 110 centimeters early on November 7. The city has for years been wrestling with the problems posed by the threat of rising sea levels. (Photo by Olivier Morin/AFP Photo)