Beijing woke up to orange-tinted skies Saturday as the strongest sandstorm so far this year hit the country's north, delaying some flights at Beijing's international airport. The Chinese Academy of Sciences has estimated that the number of sandstorms has jumped six-fold in the past 50 years to two dozen a year. The latest sandstorm has also affected the regions of Xinjiang and Inner Mongolia and the provinces of Shanxi, Shaanxi and Hebei.