Revellers from Russia parade during the Aoussou Carnival in Sousse, Tunisia July 26, 2015. (Photo by Anis Mili/Reuters)

Models wear creations by brand Leonisa during Colombiamoda fashion event in Medellin, Colombia, July 28, 2015. (Photo by Fredy Builes/Reuters)

A model presents a creation by Paradizia during Colombiamoda fashion event in Medellin, Colombia, July 29, 2015. (Photo by Fredy Builes/Reuters)

A chicken seller carries his chickens on his head in the market in Peshawar, Pakistan, August 20, 2015. (Photo by Khuram Parvez/Reuters)

A man enters an adult amusement establishment in Shinjuku's nightlife district of Kabukicho in Tokyo, August 27, 2015. (Photo by Thomas Peter/Reuters)

A couple hugs while standing near a Christmas tree made out of plastic bins and plastic hampers outside the Museum of History in Monterrey, Mexico, December 4, 2015. The humble Christmas tree has a rich history, from evergreen trees used to symbolise eternal life in Ancient Egypt to tree worship among pagan Europeans. The modern version has its origins in Germany, where the song “O Tannenbaum” is still a festive favourite. Today the traditional tree with lights and decorations appears in cities including Washington, Moscow and Beirut. Alternative constructions range from recycled rubbish in Mexico City to old window frames in Rakvere, Estonia. Whatever the shape or size, the message is the same: Merry Christmas. (Photo by Neil Hall/Reuters)

Dhofar Region, Oman. Much of Oman is desert, but the Arabian Sea coast in the Dhofar region represents a startling difference in climate. This coastal region catches the monsoon rains, or khareef, during the summer months. Drenching rains fall primarily on the mountainous ridge that separates the lush, fertile areas along the coast from the arid interior, recharging streams, waterfalls and springs that provide plentiful water supplies in the fertile lowlands for the remainder of the year. Image taken by Landsat 5 on April 2, 2005. (Photo by USGS/NASA)

In this photo taken Tuesday, February 2, 2016, asylum seekers gather round a fire as they cook a meal overlooking the temporary Altnes camp refugee camp on the island of Seiland, northern Norway. Waiting for their asylum claims to be processed, hundreds of people in emergency shelters in Hammerfest and neighboring towns are slowly getting used to the extreme climate and unfamiliar customs of the High North. They say they have adapted to the cold – the temperature rarely drops below minus 10 degrees C (14 F) along the coast, though it gets much colder further inland. It’s the darkness that throws them off. (Photo by Alastair Grant/AP Photo)