A key airport in Sichuan Province reopened at noon after thick fog affected nearly 200 flights and stranded more than 15,000 passengers since Sunday, Xinhua reported. The Shuangliu International Airport in Chengdu, capital of Sichuan, resumed operation at about 11:40 a.m. after two closures, each lasting for more than five hours on Sunday and Monday. Visibility reduced to less than 10 meters early Sunday morning, far less than the minimum 500 meters required for taking off. Airport staff were trying to arrange more flights to transport all passengers by midnight, according to Lu Junming, airport spokesman. The airport is one of the busiest transport and distribution centers in southwest China. Eight key expressways linking Chengdu to surrounding regions remained paralyzed by Monday noon, as visibility dropped to less than 50 meters. The downtown area was submerged in a fog that forced vehicles to turn on fog lights and crawl in patience. Airport authorities said more fog was expected Tuesday because of humid climate conditions.