Relationship between atmospheric rivers and aerosol atmospheric rivers in the Iberian Peninsula

Recently, the water vapour atmospheric river (AR) concept was extended to aerosols, introducing the term aerosol atmospheric river (AAR) into the literature. Equivalently to ARs, AARs are narrow and transient filaments of intense aerosol transport in the lower troposphere. The Iberian Peninsula (IP) is one of the regions regularly affected by ARs and is also frequently impacted by Saharan dust outbreaks. While the impacts of ARs in the IP were extensively studied, there is a lack of regional studies on the impact of AARs in the IP. Moreover, the relationship between ARs and AARs in the IP has not yet been investigated. Therefore, this work aims to better understand the relationship between ARs and AARs in the IP and to quantify the co-occurrence of these phenomena. In this sense, a modified algorithm originally designed to detect ARs was applied to the Modern-Era Retrospective analysis for Research and Applications, version 2 (MERRA-2) reanalysis in order to identify the AARs that affected the IP over a 20-year period. Five aerosol types were used: dust, sea salt, sulphate, organic carbon and black carbon. In this presentation, we will show and discuss the climatology, the seasonality, and the characteristics of each type of Iberian AAR and how often these events are associated with ARs. This work contributes to a better understanding of the differences between ARs and AARs, as these phenomena share similarities but can also have different origins and trajectories.

 

This work was supported by the Portuguese Foundation for Science and Technology (FCT) through a PhD grant (2023.03574.BD) for Diogo Luís.