A Chinese woman wears a mask to protect from particles blown in during a sandstorm as she walks in the street on May 4, 2017 in Beijing, China. Sandstorms are common in northern China during the spring season and are caused when heavy winds from Mongolia in the north brings sand and pollutants that can blanket Chinese cities and cause air quality to deteriorate. (Photo by Kevin Frayer/Getty Images)

In this April 1, 2002, file photo, Mike Cole, of Jenkintown, Pa., right, performs a kick-flip over a trash can with his skateboard as tourists pose for photos in front of artist Robert Indiana's sculpture in John F. Kennedy Plaza, also known as Love Park, in Philadelphia. Granite slabs from Philadelphia's famed Love Park, a skateboarding mecca though for a long stretch an illegal one, are being shipped in 2017 to the city of Malmo, Sweden, nearly 4,000 miles away, for use in construction of a skate park there. (Photo by Douglas Bovitt/AP Photo)

A herd of elephants cross a road that passes through the flooded Kaziranga National Park in the northeastern state of Assam, India, July 12, 2017. (Photo by Anuwar Hazarika/Reuters)

Tea garden workers carry sacks of tea leaves at Fatikchera tea garden estate on the outskirts of Agartala, India, May 10, 2016. (Photo by Jayanta Dey/Reuters)

Female labourers wearing helmets take a break from laying underground electricity cables in Ahmedabad, India, March 7, 2016. (Photo by Amit Dave/Reuters)

In this September 4, 1963, file photo, a police officer carries off a demonstrator holding a Confederate flag after a group of demonstrators protested enrollment of two African-Americans at Ramsay High School in Birmingham, Ala. The Confederate battle flag has been removed from South Carolina's Statehouse grounds, in the wake of the massacre of nine African-Americans, including a state senator, at an historic black church in Charleston in June 2015. (Photo by AP Photo)

An Zi, is squashed amongst other commuters in a subway train on his way to work in Beijing, China, November 12, 2015. An, a movie producer, moved to Dongsanqi village in Changping this year. His commute to work can take about 2 hours, with transportation costs topping 200 yuan a month, or about a fifth of his monthly rent. (Photo by Jason Lee/Reuters)

Job seekers carry a woman who fainted at the Indonesia Spectacular Job Fair 2015 at Gelora Bung Karno stadium in Jakarta August 12, 2015. Indonesia's gross domestic product grew at 4.67 percent in the second quarter, its slowest pace in six years. Since he took office last October, Widodo's government has passed a raft of measures aimed at boosting industry and consumption that have been criticized by investors as protectionist. (Photo by Reuters/Beawiharta)