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)

Italy's Mount Etna, Europe's tallest and most active volcano, spews lava as it erupts on the southern island of Sicily, Italy, February 28, 2017. (Photo by Antonio Parrinello/Reuters)

Eddie Ladd and Gwyn Emberton perform as Dylan and Caitlin Thomas in “Caitlin” at the Lauriston Hall, Edinburgh, Scotland on August 25 2017. (Photo by Mary Turner/Reuters)

People participate in a wet t-shirt contest on a stage while people party and celebrate on the beach at Clayton's Beach Bar and Grill in South Padre Island, Texas, USA, 11 March 2018. Spring break draws thousands of kids from all over the country to many different locations to celebrate each year. (Photo by Larry W. Smith/EPA/EFE)

In this Thursday, May 31, 2018 photo, a temporary worker using a lantern collects white asparagus from a field in Caparroso, around 85 km (52 miles) from Pamplona, northern Spain. Dubbed the “white gold” of these northern Spanish farms because of their color and the high price they fetch in markets and restaurants around the world, the stringy delicacy is planted every fall and picked each year between April and June, at the height of the spring. (Photo by Alvaro Barrientos/AP Photo)

In this November 12, 2015, file photo, Mt. Everest is seen from the way to Kalapatthar in Nepal. An American climber has died near the summit of Mount Everest and an Indian climber is missing after heading down from the mountain following a successful ascent, expedition organizers said Sunday. (Photo by Tashi Sherpa/AP Photo)

Thailand’s Surasak Waenwiset tries a shot as Hungary’s Marcell Fenyvesi stands nearby, during their Beach Handball Men’s Tournament match in Tecnopolis Park, during the Youth Olympic Summer Games in Buenos Aires, Argentina on October 9, 2018. (Photo by Florian Eisele/AP Photo)

The singing group The D-Day Darlings take part in the unveiling ceremony of a permanent war memorial, created by artist and writer Fabian Peake, at St Pancras International railway station in London, Britain, November 8, 2018. (Photo by Peter Nicholls/Reuters)