A woman wears a face mask in the part of the city near neighbourhoods known for burning coal for heating in Ulaanbaatar, Mongolia January 26, 2017. Not many people in Ulaanbaatar wear masks to protect themselves against pollution. (Photo by B. Rentsendorj/Reuters)

In this May 2016 photo released by The Ocean Agency/XL Catlin Seaview Survey, a boat sails near a coral reef that has been bleached white by heat stress in the Maldives. oral reefs, unique underwater ecosystems that sustain a quarter of the world's marine species and half a billion people, are dying on an unprecedented scale. Scientists are racing to prevent a complete wipeout within decades. (Photo by The Ocean Agency/XL Catlin Seaview Survey via AP Photo)

A U.S. Marine leads training on a shooting range in France in an undated photo taken during the First World War. (Photo by Reuters/Courtesy Library of Congress)

People ride a bus as they travel in Yangon, Myanmar January 14, 2017. Picture taken January 14, 2017. (Photo by Soe Zeya Tun/Reuters)

A general view of atmosphere at the annual VOLT Festival in Sopron, 208 kms west of Budapest, Hungary on August 16, 2016. (Photo by Rockstar Photographers)

A woman stands on the footbridge over the river Garry near Pitlochry, Scotland, Britain on October 10, 2018. (Photo by Russell Cheyne/Reuters)

Models perform during a Muslim fashion show an airport train in Jakarta, Indonesia on Thursday, May 2, 2019. The fashion show was held to great to upcoming fasting month of Ramadan, the holiest month in Muslim calendar. (Photo by Tatan Syuflana/AP Photo)

Kyle Larson (42) flips as he makes contact with Jeffrey Earnhardt (81) on the back stretch during a NASCAR Cup Series auto race at Talladega Superspeedway, Sunday, April 28, 2019, in Talladega, Ala. (Photo by Greg McWilliams/AP Photo)