A dog takes a rest under a destroyed house at a site where a landslide swept through a residential area at Asaminami ward in Hiroshima, western Japan, August 20, 2014. At least 36 people, including several children, were killed in Japan on Wednesday, when landslides triggered by torrential rain slammed into the outskirts of the western city of Hiroshima, and the toll could rise further, police said. Seven people were missing after a month's worth of rain fell overnight, loosening slopes already saturated by heavy rain over the past few weeks. (Photo by Toru Hanai/Reuters)

(L-R) Edmea Pereira, 69, Elsa Rodrigues, 61, and Osmidio Conde, 71, take part in their surf class in Santos, Sao Paulo state, Brazil, March 16, 2016. When work is up, surf is up in Brazil, as a group of retired citizens take to the waves in keep-fit, keep-young sessions at a surf school in the city of Santos. The classes are run for free, three times a week at the Cisco Arana school, which aims to prove that age is just a number. (Photo by Nacho Doce/Reuters)

Howard Jackson, a Liberian migrant, poses for a portrait in the Andalusian capital of Seville, southern Spain March 7, 2016. Jackson escaped civil war and spent three years crossing Africa before reaching Spain. Dressed up in one of his more than 200 costumes, from Peter Pan to Little Red Riding Hood, he is a well-known figure at an intersection entering the Spanish city of Seville where he has sold tissues to motorists for over a decade. Jackson is studying law and wants to become a judge. (Photo by Marcelo del Pozo/Reuters)

A debutante from a local academy looks at her mobile phone as she waits to take part in the Vienna Ball at the Kempinski Hotel, March 19, 2016, in Beijing. The ball, which is an event organized by the luxury Kempinski Hotel chain and the City of Vienna, brings together both Chinese and foreign members of the capital's elite class. Despite a slowing economy, private wealth has soared in China after decades of rapid growth. A record number of high net worth individuals and families has fuelled a market for luxury goods, services, and events catering to China's burgeoning elite class. (Photo by Kevin Frayer/Getty Images)

A masked man in military fatigues brings a blindfolded Irma Krat, arrested and held by pro-Russian protestors before her meeting with journalists near of occupied police station in Slaviansk, Ukraine, 21 April 2014. Pro-Russian activists are demanding broader autonomy from Kiev and closer ties to Russia. Pro-Russian activists continued occupying government, police and other administrative buildings in eastern Ukrainian cities, in defiance of an ultimatum by the Ukrainian government to lay down their weapons. Russia, the United States, the European Union and Ukraine on 17 April had agreed on steps to de-escalate the crisis in Ukraine during talks in Geneva, Switzerland. (Photo by Roman Pilipey/EPA)

Seized plastic handguns which were created using 3D printing technology are displayed at Kanagawa police station in Yokohama, south of Tokyo, in this photo taken by Kyodo May 8, 2014. Yoshimoto Imura became the first man to be arrested in Japan for illegal possession of two guns he created himself using 3D printing technology, Japanese media said on Thursday. The 27-year-old, a college employee in the city of Kawasaki, was arrested after police found video online posted by Imura claiming to have produced his own guns. Gun possession is strictly regulated in Japan. Police raided Imura's home and found five guns, two of which could fire real bullets, Japanese media said. (Photo by Reuters/Kyodo)

The rotating updraft base of a supercell thunderstorm, and a rear flank downdraft containing rain and hail, backlit by the setting sun, on May 10, 2014, in Climax, Kansas, United States. To most of us, dark clouds on the horizon usually means rain – but here in Kansas, they can also signal the start of a supercell. The huge formations, also known as rotating thunderstorms, are among the most powerful weather phenomenon found over land. They can occur anywhere where the conditions are right, but are normally found in more arid climates. These awe-inspiring supercells were captured south of Climax city by storm chaser Stephen Locke. (Photo by Stephen Locke/Barcroft Media)

Growing cities, overuse of fertilizers and factory wastewater have degraded China's water supplies to the extent that half the nation's rivers and lakes are severely polluted. China aims to spend $850 billion to improve filthy water supplies over the next decade, but even such huge outlays may do little to reverse damage caused by decades of pollution and overuse in Beijing's push for rapid economic growth. Photo: Fishermen row a boat in the algae-filled Chaohu Lake in Hefei, Anhui province, June 19, 2009. (Photo by Jianan Yu/Reuters)