For Nick Ward, a snow-boarding enthusiast from the United States who lives in Beijing, the only issue holding back his skiing passion in the Chinese capital is the heavy haze that sometimes shrouds North China.

"I've never seen the smog back home (in New Hampshire, a northeastern state of the US). It happens now and then here even in winter, and it's really an obstacle for outdoor sports," said Ward, who has been in Beijing for two years.

The severe air pollution in Beijing, especially in autumn and winter, has been a headache for outdoor exercisers and sporting event operators in recent years. However, Beijing's joint bid with Zhangjiakou, Hebei province, for the 2022 Winter Olympic Games has offered a chance to reduce the pollution through cooperative efforts.

"The bidding and hosting of the Winter Olympics require good air quality and environment, so it can motivate us (the governments) to take tougher measures to upgrade the economic structure, thus cutting the emission of air pollutants," said Wang Hui, head of the publicity department of the Beijing 2022 Olympic Winter Games Bid Committee.

Hebei has witnessed frequent heavy smog since 2013, with seven of its cities listed in the top 10 worst-polluting major cities, the Ministry of Environmental Protection said.

In Beijing, about 30,000 runners from home and abroad participated in the marathon on Oct 19, breathing the haze on their long journey.

"We have felt the urgency of controlling the air pollution to guarantee our residents clean air," Wang said. "The joint efforts between Beijing and its neighbors are quite important."

Zhangjiakou, northwest of Beijing, always has better air quality because it is located upwind.

"But the city will take efforts to keep the air quality good for the bidding, and will cooperate with Beijing on the joint control of air pollution," Zhangjiakou bidding office director Zhang Chunsheng said.

Zhang said the good air quality in Zhangjiakou has been an attraction for Beijing residents hiking in summer and skiing in winter. It's the city with the best air quality of the 37 major northern areas in 2013, the ministry said.

Echoing the authority's determination on improving air quality, many residents in Zhangjiakou shared their confidence.

"I think the governments can present a wonderful environment to the participants and the world if we get the chance of hosting the Winter Olympics," said Yan Xiufang, a 65-year-old resident of Zhangjiakou, adding that her community has organized activities to promote a green lifestyle.

Sun Xiaochen contributed to the story.

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