Particle size distribution and particulate matter concentrations during synoptic and convective dust events in West Texas

Abstract. Dust events are an important and complex constituent of the atmospheric system that can impact Earth's climate, environment, human health. The frequency dust in Southern High Plains West Texas has increased over past 2 decades, yet their on air quality this region is still unclear. This due to fact there only one monitoring station measures PM2.5 concentrations (particulate matter with aerodynamic diameter < 2.5 µm), no information other PM sizes or particle size distribution. Aerosol Research Observation Station (AEROS) unit provides insight into local variation concentration during different allows for a better understanding quality. As area prone events, we were wondering if generated by meteorological causes (synoptic vs. convective) would present similar distributions. Thus, project, three measured AEROS compared. Each event originated from direction lasted duration. One was synoptic (10 April 2019) two convective (5 21 June 2019). Measurements mass number concentration, distribution, conditions each (on 10 April) longer (12 h) had stronger wind speed (up 22.1 m s−1), whereas respective 5 20 30 min lower speeds 16.5 13.4 s−1). based daily hourly values showed quality, measurements underestimate events. Observations shorter timescale min) reveal true A comparison distribution all presented increase particles 0.3–10 µm range. Comparisons > show very high Some even ∼ orders magnitude compared time before event. leads us speculate underestimated current (hourly basis) method.