Boys play with a ball in front of oilfields burned by Islamic State fighters in Qayyara, south of Mosul, Iraq November 23, 2016. (Photo by Goran Tomasevic/Reuters)

A boy carries sugar cane through a farm on the outskirt of Zaria in Nigeria's northern state of Kaduna November 15, 2016. (Photo by Akintunde Akinleye/Reuters)

A woman is dragged away by Chinese men moments after she was seen talking to journalists near the site of a reported explosion outside the U.S. Embassy in Beijing, China, Thursday, July 26, 2018. A man exploded a small homemade bomb outside the U.S. Embassy in Beijing on Thursday, injuring only himself, according to police and an embassy spokesperson. (Photo by Ng Han Guan/AP Photo)

A girl uses a mattress as a raft during the flood after the Xepian-Xe Nam Noy hydropower dam collapsed in Attapeu province, Laos July 26, 2018. At least 26 people were killed and over 3,000 people stranded after a hydroelectric dam built collapsed in southeastern Laos, destroying thousands of homes and leaving an unknown number of dead. (Photo by Soe Zeya Tun/Reuters)

Aerial view of a boat working in the green water of Taihu Lake covered by blue-green algae, Wuxi city, Jiangsu province, China on May 23, 2018. (Photo by Imaginechina/Rex Features/Shutterstock)

Factory waste including dyes from the many textile factories in the region drain into a tributary of the Citarum river on August 27, 2018 outside Bandung, Java, Indonesia. (Photo by Ed Wray/Getty Images)

This year’s World Nomad Games, a celebration of nomadic heritage, took place in the Issyk-Kul province of Kyrgyzstan. Eleanor Moseman photographed female competitors who had travelled from all over central Asia and eastern Europe, and explored the difficulties and challenges they face as competitors. (Photo by Eleanor Moseman/The Guardian)

Border between Sweden and Norway at Moldusen. An approximately 20-meter wide clearing in the forest separates the two Scandinavian nations, consequently cutting Finnskogen in two. Grue Finnskog 2016. (Photo by Terje Abusdal/The Washington Post)