A house burns as the Butte fire rages through Mountain Ranch, California September 11, 2015. Evacuation orders were expanded to thousands of homes in northern California's Sierras on Friday as the rapidly spreading wildfire roared for a third day through drought-parched timber and brush, threatening mountain communities. (Photo by Noah Berger/Reuters)

Sandstone sculpted by water and wind erosion is seen in a slot canyon, one of hundreds that surround Lake Powell near Page, Arizona, May 26, 2015. Lake Powell on the Colorado River provides water for Nevada, Arizona and California. A severe drought in recent years, combined with withdrawals that many believe are not sustainable, has reduced its levels to only about 42 percent of its capacity. (Photo by Rick Wilking/Reuters)

A young Chinese girl dressed in Christmas costume, hugs a pedestrian on a street to celebrate Christmas in Nanjing city, east China's Jiangsu province, 23 December 2015. (Photo by Imaginechina/Splash News)

Tsunami, an eleven year old female Sumatran Orangutan eats a fruit platter during her birthday celebration at the National Zoo Ape Center in Kuala Lumpur, Malaysia, Thursday, December 31, 2015. (Photo by Manan Vatsyayana/AFP Photo)

Filipino typhoon victims walk through heavy mud in the typhoon hit town of Taft, Samar island, Philippines, 08 December 2014. Typhoon Hagupit weakened into a tropical storm as it moved towards the Philippine capital after killing at least 27 people and displacing more than one million people in the eastern and central provinces. Hagupit slammed into the country's eastern coast on 06 December evening, bringing heavy rains and gale-force winds that flattened homes, ripped off roofs, and knocked out power and communications. (Photo by Francis R. Malasig/EPA)

Justin Nelzen, in red vest, joins others as they work to rescue up to 70 horses along Cypresswood Drive near Humble along Cypress Creek, Monday, April 18, 2016, in Houston. More than a foot of rain fell Monday in parts of Houston, submerging scores of subdivisions and several major interstate highways, forcing the closure of schools and knocking out power to thousands of residents who were urged to shelter in place. (Photo by Mark Mulligan/Houston Chronicle via AP Photo)

Zulmira Jesus poses for a portrait at a street in Povoa de Agracoes, near Chaves, Portugal April 19, 2016. In the villages of Agracoes and Povoa de Agracoe, the steady drip-drip of emigration has brought down population numbers from more than 50 residents to fewer than a dozen each. These remaining villagers share the same glum acceptance that, after they have gone, their villages will die out too. It is the same desolate picture in scores of other backwater settlements in Portugal's interior, north to south. (Photo by Rafael Marchante/Reuters)

British visitors wearing Bavarian costumes walk ahead the opening of the traditional Bavarian Oktoberfest festival at the Theresienwiese in Munich, southern Germany, on September 20, 2014. Germany's world-famous Oktoberfest kicks off with millions of revellers set to soak up the frothy atmosphere in a 16-day extravaganza of lederhosen, oompah music and, of course, beer. (Photo by Karl-Josef Hildenbrand/AFP Photo/DPA)