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)

A paddler races in a giant pumpkin during the annual regatta on Lake Pisiquid in Windsor, Nova Scotia, Sunday, October 11, 2015. Participants hollow out the massive gourds and pilot them across the 500 meter course. (Photo by Andrew Vaughan/The Canadian Press via AP Photo)

Cattle keepers from the Dinka tribe perform a traditional dance after a prayer session for peace and good health along the route to Rajaf Payam outside the capital Juba October 18, 2014. (Photo by Jok Solomon/Reuters)

White lioness Azira lies in the cage with her three white cubs, on February 4, 2014. Zoo owner Andrzej Pabich says white lions often have defects that prevent giving birth, or the mother rejects her cubs, but Azira has been patiently feeding and caring for her little ones. (Photo by Czarek Sokolowski/Associated Press)

Two Bulgarian tourists pose in front of the Eiffel Tower in Paris on their last day in the capital on March 24, 2014. (Photo by Franck Fife/AFP Photo)

A fan looks at the Germany flag before the 2014 World Cup final between Germany and Argentina at the Maracana stadium in Rio de Janeiro July 13, 2014. (Photo by Darren Staples/Reuters)

North Korean soldiers keep watch at the bank of the Yalu River, near the North Korean town of Sinuiju, opposite Dandong in China's Liaoning province, September 10, 2016. (Photo by Thomas Peter/Reuters)

in Qayyarah, about 31 miles (50 km) south of Mosul, Iraq, Sunday, October 23, 2016.in Qayyarah, some 50 kilometers south of Mosul, Iraq, Sunday, Oct. 23, 2016. Islamic State fighters torched a sulfur plant south of Mosul, sending a cloud of toxic fumes into the air that mingled with oil wells the militants had lit on fire to create a smoke screen. (Photo by Marko Drobnjakovic/AP Photo)