Rising Dust Storm Activity in the Southwestern United States: Evidence from Long-Term Multiplatform Observations

Climate models consistently predict a drying trend in the already arid Southwestern United States, aiding speculation of more dust storms and even catastrophic environmental disasters such as desertification and another “Dust Bowl”. This work reports long-term variations and trend of windblown dust storm activities over Southwestern US from long-term multi-platform observations. As part of the NASA National Climate Indicator team, we have assembled three largest data sets of dust storms over the United States, using three long-term monitoring platforms, including the IMPROVE (Interagency Monitoring of Protected Visibility Environments) network and U.S. Environmental Protection Agency (EPA)’s Air Quality System (AQS), and the Moderate Resolution Imaging Spectroradiometer (MODIS)aboard the NASA Terra and Aqua satellites. Dust trends from these networks are compared at regional scale and also at selected areas with collated measurements. In addition, we examine the changing rate of dust activity with regard to sampling frequency, timing and detection capability. Next, we investigate the relationships between dust and other environmental variables, including both short-term variables (such as wind speed and soil moisture) and low-frequency variables (such as Pacific Decadal Oscillation) to understand the climatic drivers of the observed trend. Finally, we will discuss the imminent risks imposed by dust storms, including infectious diseases and highway accidents.