The strong westerly jet in the upper troposphere is linked to the Mongolia cyclone and frontogenesis at low level which can cause strong wind and further provides the dynamic factor for the increased DWF in Beijing.

• 春季对流层高层的东亚西风急流增强能使低空的蒙古气旋加强和锋生；从而引起地面大风；为沙尘天气频次的增加提供动力条件.