investigating lagged cross-correlation between wind erosion and drought in southern iran’s arid regions

This study sought to detect the highest temporal correlation between wind erosion and drought in southern iran’s arid lands based on the standardized precipitation index (spi) and standardized dust storm index (sdsi) over a 50-year period (1965-2014). using the mann- kendall test, changes in spi (as a proxy of meteorological drought) and sdsi (as a proxy of wind erosion) trends were analyzed in temporal resolution (3, 6, 9, 12, 18, and 24 monthly time series). the wind erosion’s response time to drought was estimated by lagged cross-correlation. the results revealed a decreasing trend in the spi time series, particularly in the long-term series (12, 18, and 24-month), and an increasing trend in the sdsi series in different time scales, from short-term to long-term series. these findings indicate the exacerbation of drought and wind erosion in the study region. moreover, the cross-correlation analysis showed that the relationships between spi and sdsi were negative at the level of 5% in all the time series. the maximum correlation was obtained from the cross-correlation between the 12-month spi and 18-month sdsi without time lag (r= -0.22; α<0.05). these results indicated that in southern iran’s arid regions, changes in dust events had been affected by long-term drought. therefore, it is expected that after long-term droughts, which considerably affect the soil moisture contents, the dust storms are intensified. the finding of this research can help planners take necessary measures against sand and dust storm hazards.