A girl watches an acrobatic performance at the Longtan park as the Chinese Lunar New Year, which welcomes the Year of the Monkey, is celebrated in Beijing, China February 9, 2016. (Photo by Damir Sagolj/Reuters)

Fifth-grade students of the General Yermolov Cadet School get prepared before their first military tactical exercise on the ground, which includes radiation resistance classes, forest survival studies and other activities, in Stavropol, Russia, September 10, 2016. Picture taken September 10, 2016. (Photo by Eduard Korniyenko/Reuters)

A sign advising to pray for rain hangs above an exhibit area at the 47th Annual World Ag Expo in Tulare, February 12, 2014. About a hundred years ago, when urban water systems were being developed throughout the state, the city of Sacramento wrote protections from metering into its charter, vowing that residents would always have the right to use as much water as they needed. But on Tuesday, the state's top water regulators released a framework for enforcing California's first statewide mandatory restrictions on urban water use – cuts of 25 percent for non-agricultural users ordered last week by Democratic Governor Jerry Brown as a devastating drought enters its fourth year. (Photo by David McNew/Reuters)

Francisco da Silva Vale, 61, cools off fish with ice produced on solar-powered ice machines at Vila Nova do Amana community in the Sustainable Development Reserve, in Amazonas state, Brazil, September 23, 2015. Three solar-powered machines, are producing about ninety kilos of ice per day, in a region with poor access to electric energy, which used to be produced only with diesel oil, in the Amazon rain forest. (Photo by Bruno Kelly/Reuters)

A general view of dried-up rivers in the Pilbara region of Western Australia December 2, 2013. Western Australia's Pilbara region, which is the size of Spain, has the world's largest known deposits of iron ore and supplies nearly 45 percent of global trade in the mineral. (Photo by David Gray/Reuters)

People fall down as they try to form a human pyramid to break the “Dahi handi”, an earthen pot filled with curd, an integral part of celebrations to mark Janmashtami in Mumbai, India, Monday, August 18, 2014. Hindu devotees take part in the celebration in which an earthen pot is suspended high above the ground and groups of young men and children form a human pyramid to reach the pot and break it. The festival celebrates the birth of Hindu god Lord Krishna, one of the most popular gods in Hinduism. (Photo by Rafiq Maqbool/AP Photo)

Bangladeshi railway police try to clear line, as thousands of Bangladeshi Muslims gather to board trains to return home after attending three-day Islamic Congregation on the banks of the River Turag in Tongi, 20 kilometers (13 miles) north of the capital Dhaka, Bangladesh, Sunday, January 26, 2014. (Photo by A. M. Ahad/AP Photo)

A model of the New Horizons spacecraft is seen at a live television program on NASA television celebrating the spacecraft's closest proximity to Pluto, at Johns Hopkins University Applied Physics Laboratory, site of the mission operations center, in Laurel, Maryland, USA, 14 July 2015. At approximately 7:49 am ET (11:49 am GMT), 14 July, New Horizons was scheduled to be as close to Pluto as the spacecraft will get; about 7,800 miles (12,500 kilometers) above the surface, following a journey of more than nine years and three billion miles. This is the first mission to the Pluto System and the Kuiper Belt. (Photo by Michael Reynolds/EPA)