Interdecadal feature and mechanism of global dusty weather

Abstract

Dusty weather (including dust storms, blowing dust and floating dust) represents a catastrophic weather phenomenon with extensive adverse environmental impacts. However, its natural variability and underlying mechanisms at the global scale remain insufficiently explored in prior research. This study investigates the spatiotemporal distribution characteristics and driving mechanism of global dusty weather using long-term station observations and reanalysis data. Our findings reveal a significant declining trend in dusty weather over the Taklimakan Desert and southwestern Sahara Desert from 1979 to 2023, whereas an increasing trend is observed over the northern Sahara Desert, Arabian Desert and Gobi Desert during the same period. Temporally, global dusty weather activity exhibits a decline from 1979 to 1999, followed by an interdecadal-scale oscillation with cycles of 10–14 years after 1999. The mechanistic analysis demonstrates that Atlantic climate modes—particularly the South Atlantic Subtropical Dipole (SASD) and the North Atlantic Oscillation (NAO)—play a dominant role in modulating the interdecadal variability of dust storms, with correlation coefficients of −0.44 (SASD) and 0.37 (NAO), respectively. Consequently, energy convergence over dust source regions, modulated by the SASD and NAO, stimulates low-pressure troughs and intensified westerlies in the Northern Hemisphere, alongside warm high-pressure systems in the Southern Hemisphere, both of which enhance dust storms. Our results advance the understanding of global dusty weather dynamics and offer valuable insights for future dust storms prediction.