Numerical research of extreme wind-induced dust transport in a semi-arid human-impacted region of Mexico

A numerical research is carried out to investigate the regional impact of extreme wind-induced dust transport in the central-northern part of Mexico. In boreal winter, strong wind soil erosion processes occur in the arid zones of the Mexican highlands, as a consequence of land use change and land cover change. The effect of land use change and land cover change has consequences in the atmospheric circulation, by altering the balance in solar radiation, albedo, soil moisture and texture, aerodynamic roughness and other surface properties. The anthropogenic impact of land use change from natural vegetation to agriculture lands developed into land degradation and air quality loss by large dust fluxes into the atmosphere. To investigate the magnitude of these erosion processes, we carried out the numerical modeling of a strong dust storm during the passage of a cold front on 18 March 2008. An algorithm based on the friction velocity was implemented for estimating the flux of particulate matter less than 10 μm (PM10) into the atmosphere. It was possible to show how the plume of high concentration of particulate matter propagates through the complex topography of the highland and of the Eastern Sierra Madre to reach large urban zones in the northern part of Mexico and Southern of Texas. In our numerical simulation we estimated roughly that the fraction of PM10 emitted during this event was of the order of 9162.72 ton. A direct effect of dust particles is appreciated in the reduction of measured solar radiation.

► In this study we investigate the strong impact of human activities impact on semi-arid environments. ► We point out the importance of researching wind erosion and its relationship with soil loss and desertification process. ► To document dust storms in the Mexican highlands of northern Mexico, we selected a case study in the State of Zacatecas. ► We find that land cover change generates a local environmental impact affecting the weather in the Mexican highlands. ► We conclude that a relatively small human-impacted area is converted in a source of dust affecting large regions.