Cars run on the street during a sandstorm in Zhangye City, northwest China's Gansu Province, Nov. 25, 2018. The local meteorological center issued a yellow alert for sandstorm. (Xinhua/Chen Li)

Citizens walk on the street during a sandstorm in Zhangye City, northwest China's Gansu Province, Nov. 25, 2018. The local meteorological center issued a yellow alert for sandstorm. (Xinhua/Cheng Xuelei)

Citizens walk on the street during a sandstorm in Zhangye City, northwest China's Gansu Province, Nov. 25, 2018. The local meteorological center issued a yellow alert for sandstorm. (Xinhua/Cheng Xuelei)

Sandstorm is seen in Zhangye City, northwest China's Gansu Province, Nov. 25, 2018. The local meteorological center issued a yellow alert for sandstorm. (Xinhua/Chen Li)

Sandstorm is seen in Zhangye City, northwest China's Gansu Province, Nov. 25, 2018. The local meteorological center issued a yellow alert for sandstorm. (Xinhua/Chen Li)