Distinctive dust weather intensities in North China resulted from two types of atmospheric circulation anomalies

Abstract. Dust weather in North China (NC) has worsened in recent years, posing adverse impacts on the environment, human health, and the economy. In 2021, the "3.15" super dust storm raised Beijing's PM₁₀ (particulate matter with a diameter less than 10 μm) concentrations above 7000 μg m⁻³, while 2023 witnessed the highest spring dust weather frequency in nearly a decade. Although previous studies have proposed that synoptic systems such as the Mongolian cyclone and cold high can induce dust weather in NC, there has been less focus on the cold high. Furthermore, the differences in PM₁₀ concentrations in NC caused by the two synoptic systems have not been quantified. This study demonstrates that the Mongolian cyclone was responsible for 62.4 % of the dust weather in NC, while the remaining 37.6 % was primarily caused by the cold high. The dust intensity induced by the Mongolian cyclone was stronger than that of the cold high, with average maximum PM₁₀ concentrations of 3076 μg m⁻³ and 2391 μg m⁻³, respectively. The three-dimensional structure of atmospheric circulation anomalies and related dynamic mechanisms of the two types were concluded. A common predictor of the two dust weather types has also been identified. These findings contribute to enhancing the comprehension of dust weather in North China and offer valuable insights for both dust weather forecasting and climate prediction.