Ali Asair, who has left his family behind and traveled hundreds of kilometers in search for a pasture for his animals, attends to his camel in a pastoralists' settlement in the Bandarbeyla district in Somalia's semi-autonomous region of Puntland, Somalia, 24 March 2017. According to media reports, the United Nations says only 31 percent of 864 million US dollars appeal for a drought-hit Somalia is funded. The UN said the world is facing the largest humanitarian crisis since 1945, adding that more than 20 million people are facing the threat of famine in Somalia, Yemen, South Sudan and Nigeria and 1.4 million children could die from starvation this year. (Photo by Dai Kurokawa/EPA)

A Chinese woman wears a mask to protect from particles blown in during a sandstorm as she walks in the street on May 4, 2017 in Beijing, China. Sandstorms are common in northern China during the spring season and are caused when heavy winds from Mongolia in the north brings sand and pollutants that can blanket Chinese cities and cause air quality to deteriorate. (Photo by Kevin Frayer/Getty Images)

Tea garden workers carry sacks of tea leaves at Fatikchera tea garden estate on the outskirts of Agartala, India, May 10, 2016. (Photo by Jayanta Dey/Reuters)

A child plays in front of “Etnias”, a large graffiti wall by Brazilian graffiti artist Eduardo Kobra created ahead of the Rio 2016 Olympic Games at Porto Maravilha in Rio de Janeiro, Brazil, 30 July 2016. The Olympics start on 05 August. Eduardo Kobra hopes to set a Guinness World Record for the largest graffiti created by a single artist. (Photo by Lukas Coch/EPA)

A dancer performs during the Gymnastics Rio Gala on Day 12 of the 2016 Rio Olympic Games on August 17, 2016 in Rio de Janeiro, Brazil. (Photo by Clive Brunskill/Getty Images)

Revellers battle with tomato pulp during the annual “Tomatina” (tomato fight) festival in Bunol near Valencia, Spain, August 31, 2016. (Photo by Heino Kalis/Reuters)

A Palestinian protester uses a sling shot to throw stones towards Israeli security forces during clashes on the Israeli border Eastern Gaza City, Friday, November 6, 2015. (Photo by Adel Hana/AP Photo)

Workers lay railway track in a tunnel of the Crossrail project in Stepney, east London, Britain, November 16, 2016. Crossrail, which is Europe's largest construction project, is a railway link which will connect outlying areas to the east and west of London with tunnels under the centre of the capital. (Photo by Stefan Wermuth/Reuters)