A Syrian man rides his bicycle past a man selling grains during a halt in fighting on February 29, 2016 in Douma, in the Eastern Ghouta region, east of the capital Damascus. A UN-backed ceasefire deal took hold across parts of Syria, bringing relative calm to areas where the Islamic State group and Al-Qaeda's local affiliate are not present. (Photo by Sameer Al-Doumy/AFP Photo)

A girl carries a rifle as she attends a rally by followers of the Shi'ite Houthi movement commemorating the death of Imam Zaid bin Ali in Sanaa, Yemen October 26, 2016. (Photo by Khaled Abdullah/Reuters)

Men eat oranges from a push cart along a road as a vehicle travels past them in Karachi January 22, 2015. (Photo by Akhtar Soomro/Reuters)

An Indian women offers early-morning prayers or a “puja” at a ghat early in the morning on the banks of the Betawa River in Orchha in the state of Madhya Pradesh on July 5, 2015. (Photo by Rebecca Conway/AFP Photo)

A participant covered in coloured powder gestures as she stands near a Syrian army soldier during “I Love Damascus” marathon at Umayyad Square in Damascus, Syria October 7, 2016. (Photo by Omar Sanadiki/Reuters)

A Kashmiri Shi'ite Muslim mourner flagellates himself during a Muharram procession to mark Ashura in Srinagar, India October 12, 2016. (Photo by Danish Ismail/Reuters)

A woman wearing a kimono performs an uchimizu ritual outside a pachinko game parlor in Tokyo June 30, 2015. The splashing of water onto the hot asphalt in summer is an old Japanese tradition meant to cool down the air as the water evaporates. (Photo by Thomas Peter/Reuters)

NASA's DHC-3 Otter plane flies in Operation IceBridge-Alaska surveys of mountain glaciers in Alaska in this image released on September 18, 2014. Over the past few decades, average global temperatures have been on the rise, and this warming is happening two to three times faster in the Arctic. (Photo by Chris Larsen/Reuters/NASA/University of Alaska-Fairbanks)