A Chinese man wears a mask to protect against pollution as he waits at a red light while commuting to work in heavy smog on December 8, 2015 in Beijing, China. The Beijing government issued a 'red alert' for the first time since new standards were introduced earlier this year as the city and many parts of northern China were shrouded in heavy pollution. Levels of PM 2.5, considered the most hazardous, crossed 400 units in Beijing, lower than last week, but still nearly 20 times the acceptable standard set by the World Health Organization. The governments of more than 190 countries are meeting in Paris to set targets on reducing carbon emissions in an attempt to forge a new global agreement on climate change. (Photo by Kevin Frayer/Getty Images)

A model (C) looks at her mobile phone while backstage before the araisara Sara Arai Collection show during China Fashion Week in Beijing on March 27, 2015. China Fashion Week runs from March 24 to March 31. (Photo by Wang Zhao/AFP Photo)

Bus hostesses adjusts their hair before photos outside the Great Hall of the People the eve of the opening session of the annual meeting of China's National People's Congress (NPC) in Beijing, Saturday, March 4, 2023. (Photo by Ng Han Guan/AP Photo)

A Chinese tourist uses the scarf of a friend as she is helped while she and others struggle to climb in the wind on an icy section of the Great Wall at Badaling, on a cold day after a snowfall on November 30, 2019 in Beijing, China. (Photo by Kevin Frayer/Getty Images)

Bus ushers leap as they pose for a group photo during a meeting one day ahead of the opening session of China's National People's Congress (NPC) at the Great Hall of the People in Beijing, Monday, March 4, 2019. (Photo by Mark Schiefelbein/AP Photo)

Bicycle rickshaw drivers chat as they wait for customers near the Drum Tower in a traditional neighbourhood on September 30, 2021 in Beijing, China. China will mark National Day and the Golden Week holiday from October 1st. (Photo by Kevin Frayer/Getty Images)

In this photo taken Wednesday, March 8, 2017, a hospitality staff member pose for photos near the shadow of a tall light pole near the Great Hall of the People where a plenary session of the National People's Congress is held in Beijing, China. (Photo by Ng Han Guan/AP Photo)

An elderly man uses a fan to shade himself from the sun as he walks in a public park in Beijing, Tuesday, June 7, 2016. Thursday marks the Duanwu Festival, a public holiday in China celebrated with outdoor activities including dragon boat races. (Photo by Mark Schiefelbein/AP Photo)