In this Friday, January 6, 2017, photo, a North Korean woman working at the Kim Jong Suk Silk Mill looks up from her workstation in Pyongyang, North Korea. The silk mill, named after North Korean leader Kim Jong Un's grandmother, is where 1,600 workers – mostly women – sort and process silkworms to produce silk thread that officials at the Pyongyang factory say is made into roughly 200 tons of silk a year. (Photo by Wong Maye-E/AP Photo)

A firefighter carries a woman from her car after it was caught in street flooding as a powerful storm moves across Southern California on February 17, 2017 in Sun Valley, California. After years of severe drought, heavy winter rains have come to the state, and with them, the issuance of flash flood watches in Santa Barbara, Ventura and Los Angeles counties, and the evacuation of hundreds of residents from Duarte, California for fear of flash flooding from areas denuded by a wildfire last year. (Photo by David McNew/Getty Images)

Deers walk past Indonesia's honour guard as they wait for the arrival of Saudi Arabia's King Salman bin Abdul Aziz at the presidential palace in Bogor on March 1, 2017. Cheering crowds welcomed King Salman on March 1 as he began the first visit by a Saudi monarch to Indonesia for almost 50 years, seeking stronger economic ties with the world's most populous Muslim-majority country. (Photo by Adek Berry/AFP Photo)

In this Friday, January 7, 2011 photo, people carry baskets of coal scavenged illegally at an open-cast mine in the village of Bokapahari in the eastern Indian state of Jharkhand where a community of coal scavengers live and work. The world's biggest coal users – China, the United States and India – have boosted coal mining in 2017, in an abrupt departure from last year's record global decline for the heavily polluting fuel and a setback to efforts to rein in climate change emissions. (Photo by Kevin Frayer/AP Photo)

A woman carries her child as she watches Mount Sinabung volcano spewing thick volcanic ash, as seen from Karo on July 21, 2017. Sinabung roared back to life in 2010 for the first time in 400 years, after another period of inactivity it erupted once more in 2013, and has remained highly active since. (Photo by Gatha Ginting/AFP Photo)

Waldo, a 6-year-old Tibetan Terrier belonging to Susan and Mike Leverette of Sebastian, competes in the third heat of the medium dogs division at the Hang 20 Surf Dog Classic at Carlin Park in Jupiter Saturday, August 29, 2015. “The waves are a little bigger than we are used to”, said Susan. (Photo by Bruce R. Bennett/The Palm Beach Post)

A migrant woman pulls a girl out of the water as refugees and migrants arrive on an overcrowded dinghy in rough sea on the Greek island of Lesbos, after crossing a part of the Aegean Sea from the Turkish coast, October 2, 2015. A record number of at least 430,000 refugees and migrants have taken rickety boats across the Mediterranean to Europe this year, 309,000 via Greece, according to International Organization for Migration figures. (Photo by Dimitris Michalakis/Reuters)

Farmer Zhang Xianping rides his pig "Big Precious" during an interview with the media, in Zhangjiakou, Hebei province, China, November 2, 2015. Zhang, a pig breeder, instead of killing it, decided to keep the two-year-old "Big Precious" as pet when its weight reached 600 kg, according to local media. (Photo by Reuters/China Daily)