A man holds his umbrella during snowfall on the Areopagitou pedestrian street beneath the Acropolis hill during snowfall in Athens, Greece, January 10, 2017. (Photo by Alkis Konstantinidis/Reuters)

A tribal Fulani man milks a cow at a local milk collecting centre in Dangwala Karfi village on the outskirts of Nigeria's northern city of Kano January 19, 2016. (Photo by Akintunde Akinleye/Reuters)

A man walks on the road between Nouahibou and Nouakchott, where three Spanish aid workers were abducted in Mauritania, December 3, 2009. (Photo by Rafael Marchante/Reuters)

A indigenous man from the Tabajara tribe is seen in Tocantins river before the I World Games for Indigenous People in Palmas, Brazil, October 21, 2015. (Photo by Ueslei Marcelino/Reuters)

A man looks inside an overturned truck after an accident along the road between Nouahibou and Nouakchott, Mauritania December 3, 2009. (Photo by Rafael Marchante/Reuters)

A man covered with mineral-rich mud smiles on a bank of lake Tus in Khakassia region, southwest of the Siberian city of Krasnoyarsk, Russia, July 16, 2016. (Photo by Ilya Naymushin/Reuters)

A man fires a weapon as he dances during a traditional excursion near the western Saudi city of Taif, August 8, 2015. Saudis usually party in such excursions as they celebrate weddings or graduations. (Photo by Mohamed Al Hwaity/Reuters)

A man fires a weapon as he dances during a traditional excursion near the western Saudi city of Taif, August 8, 2015. Saudis usually party in such excursions as they celebrate weddings or graduations. (Photo by Mohamed Al Hwaity/Reuters)