A woman wearing a scarf to cover her face looks on as she waits for a passenger bus on a smoggy morning in New Delhi, India, November 8, 2017. The Great Smog of Delhi is an ongoing severe air-pollution event in New Delhi and adjoining areas in the National Capital Territory of India, in November 2017. Air pollution at this time peaked on both PM 2.5 and PM 10 levels. It has been reported as one of the worst levels of air quality in Delhi since 1999. (Photo by Saumya Khandelwal/Reuters)

A dog walks past a mural by street artist Alex Martinez outside a shop which sells bags at Psiri area, central Athens, on Thursday, January 25, 2018. (Photo by Petros Giannakouris/AP Photo)

In this March 31, 2019 photo, an Egyptian student borrows a Bedouin wedding dress to pose for a photograph with Bedouin men from the Hamada tribe, in Wadi Sahw, Abu Zenima, in South Sinai, Egypt. Four Bedouin women are for the first time leading tours in Egypt’s Sinai Peninsula, breaking new ground in their deeply conservative community, where women almost never work outside the home or interact with outsiders. The tourists can only be women, and the tours can’t go overnight. Each day before the sun sets, the group returns to the Hamada’s home village in Wadi Sahu, a narrow desert valley. (Photo by Nariman El-Mofty/AP Photo)

A fado singer smokes a cigarrette outside a fado house at the Alfama neighborhood in Lisbon on May 8, 2019. From fado sounds to Cape Verde mornas or bossa nova: the Lisbon nights, where musicians from all over the world meet, have largely inspired Madonna's new album, who has been in the Portuguese capital since 2017. (Photo by Patrícia de Melo Moreira/AFP Photo)

A plane battling the Ferguson Fire passes the setting sun in unincorporated Mariposa County Calif., near Yosemite National Park on Sunday, July 15, 2018. (Photo by Noah Berger/AP Photo)

Muhannad al-Kadiri (R),18, and Ibrahim Eid, 16, demonstrate their Parkour skills over a military vehicle in the rebel-held city of Inkhil, west of Deraa, Syria, February 4, 2017. (Photo by Alaa Al-Faqir/Reuters)

Timbuktu: A UN peacekeeper from Burkina Faso stands guard at the Djinguereber mosque, built in the 14th century, during a visit by a UN delegation on election day in Timbuktu, Mali, July 28, 2013. (Photo by Joe Penney/Reuters)

In this Sunday, May 29, 2016 photo, fighters take a selfie while firing artillery during fight against Islamic State militants in Fallujah, Iraq. Iraqi forces this week pushed into the city's southern sections after securing surrounding towns and villages more than 50,000 people are believed to be trapped inside the Sunni majority city, about 65 kilometers (40 miles) west of Baghdad. (Photo by Anmar Khalil/AP Photo)