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)

Supporters of US President Donald Trump rally in front of a poll station at Coral Gable Branch Public Library in Miami, Florida on November 3, 2020. (Photo by Eva Marie Uzcategui/AFP Photo)

In this image released on December 09, English model Leomie Anderson and English model and actress Jourdan Dunn attend the 2020 MOBO Awards held at Exhibition London on December 07, 2020 in London, England. The MOBO Awards will be live-streamed on YouTube at 7pm and broadcast on BBC One at 10.45pm. (Photo by Michael Tubes/MOBO Organisation/Rex Features/Shutterstock)

A person takes a photo of the skyline with the Shard building in the center, at sunset, from Greenwich Park in London, Tuesday, November 24, 2020. (Photo by Yui Mok/PA Wire via AP Photo)