24SMOI Particulate Matter in the American Southwest: Detection and Analysis of Dust Storms Using Surface Measurements and Ground-Based LIDAR

Particulate matter is a complex mixture of particles suspended in the atmosphere. Various sources of particulate matter include volcanic eruptions, soil lofted by strong winds, wildfires, and particles formed from chemical reactions of air pollutants. Particles that result from soil lofted by strong winds is one example of dust pollution. The particulate matter discussed in this study is found in the planetary boundary layer (PBL), and it plays a critical role in meteorology and air quality due to its involvements in energy, latent heat, and mass transfer with the free troposphere. The PBL is expected to affect particular matter concentrations. Currently, there has not been any research on the impact of these dust events on the planetary boundary later in our region, El Paso, Tx. It is located on one of the biggest sources of dust in the Western Hemisphere, the Chihuahuan Dessert. In this study we used PM10 concentrations to detect dust events during the 2016 - 2021 period in the El Paso region. Across three air quality monitoring stations we came across a total of 683 possible dust events. Out of those cases only 74 were considered dust events due to their west wind direction. The dust events were categorized as synoptic or convective cases. Synoptic cases are associated with cold fronts while convective cases are associated with local convective systems such as thunderstorms. We observed that synoptic cases occurred most frequently during springtime while convective cases were more frequent during summer monsoon months. Synoptic cases tend to occur earlier in the afternoon with lower temperatures while convective tend to occur late evening with higher temperatures. We also found that the planetary boundary layer height collapsed after the maximum hourly PM10 concentration and then it returned to original height.