Decadal change of spring dust activity in western Iran and its mechanism

Western Iran is an important dust source region in Middle East, with strong activities occurring springtime. Based on a three-hourly meteorological station data, remarkable decadal change of frequency the spring season has been found west and southwest Iran, less during 1992–2005 (hereafter as “P1”) more frequent 2006–2015 “P2”). The signal closely associated corresponding difference precipitation atmospheric moisture transportation region. Compared P1 period 1992–2005, anomalous divergence over center East can be P2 2006–2015, suggesting transport to western from Arabian Sea, Red Persian Gulf, hence there relatively dry soil main regions study region, which favorable for emissions period. Meanwhile, westerly anomaly also upstream regions, such Iraq Syria, East. Furthermore, negative SST anomalies central North Pacific positive eastern period, phase Decadal Oscillation (PDO). Conversely, PDO This suggests that key influential factor Iran.