A person walks their dog in the morning mist at sunrise in Greenwich Park in south London on November 9, 2020. (Photo by Daniel Leal-Olivas/AFP Photo)

A couple walk in the Retiro park in Madrid on November 17, 2020 as a thick fog falls on the Spanish capital. (Photo by Gabriel Bouys/AFP Photo)

Fog covers the African Renaissance Monument in Dakar, Senegal on February 17, 2021. (Photo by Zohra Bensemra/Reuters)

A worker piles salvaged e-bikes and scooters on the back of his three wheeler before taking them to be recycled on August 31, 2021 in Beijing, China. (Photo by Kevin Frayer/Getty Images)

In this February 14, 2019 photo, a newlywed couple kisses while posing for photos at one of several free sets placed for newlyweds to take cell phone photos of themselves following a mass wedding ceremony on Valentine's Day in Mexico City. Hundreds of couples of all ages, many with their children, gathered to legally tie the knot in a mass ceremony in the capital's Venustiano Carranza neighborhood. (Photo by Rebecca Blackwell/AP Photo)

Servicewomen march in formation during a Victory Day military parade marking the 74th anniversary of the victory over Nazi Germany in the 1941-1945 Great Patriotic War, the Eastern Front of World War II, in Moscow's Red Square, Russia on May 9, 2019. (Photo by Valery Sharifulin/TASS)

A woman pushes a cart during a protest against racial inequality and call for defunding of Seattle police, in Seattle downtown, Washington, U.S. June 14, 2020. (Photo by Goran Tomasevic/Reuters)

People ride a boat on the Tianquan Lake during a foggy day in Xuyi in China's eastern Jiangsu province on November 20, 2019. (Photo by AFP Photo/China Stringer Network)