Tourists walk above a tea plantation in Enshi, Hubei province, December 27, 2015. (Photo by Reuters/Stringer)

People dressed in costumes have a break while marching during the Vijanera Festival, in the small village of Silio, northern Spain, Sunday, January 3, 2016. The Vijanera masquerade, of pre-Roman origin, is the first carnival of the year in Europe symbolizing the triumph of good over evil and involving the participation of crowds of residents wearing different masks, animal skins and brightly coloured clothing with its own complex function and symbolism and becoming the living example of the survival of archaic cults to nature. (Photo by Francisco Seco/AP Photo)

A massive sand storm cloud is close to enveloping a military camp as it rolls over Al Asad, Iraq, April 27, 2005. (Photo by Cpl. Alicia M. Garcia, U.S. Marine Corps/Reuters/U.S. Department of Defense)

A man from the Ogiek community harvests honey in Mount Elgon game reserve, where they have reached an agreement with the government allowing them to remain in their ancestral lands in western Kenya, April 26, 2016. (Photo by Katy Migiro/Reuters)

Palestinian bedouin shepherds pull their lambs into the water to wash them, in Gaza City, on April 29, 2016. Every year before the beginning of the summer, shepherds wash their herds in the sea. (Photo by Mohammed Abed/AFP Photo)

A Hindu devotee is helped by other people as she walks on burning coals during a religious procession Vel Festival of the Hindu goddess Maha Mariamman (Sheetla Mata), in New Delhi, India, 06 April 2017. People get their bodies pierced with different kinds of metal needles and rods and participate in a religious procession as thanks giving gesture to the goddess in return of their fulfilled wishes during the annual procession. (Photo by Rajat Gupta/EPA)

Farmers ride home on a tractor pulling an overloaded trailer full of straw in a village outside Faisalabad, Pakistan May 3, 2017. (Photo by Caren Firouz/Reuters)