Massive Saharan Dust Oubreak in Central Europe - Analysis of Potential Factors and Impacts

The article is a case study evaluating the massive transport of dust from the Sahara desert in the period between March and April 2024 in the Czech Republic. This event led to the declaration of smog situations due to high PM ₁₀ concentrations, with such large-scale near-ground coverage recorded for the first time. By using a combination of ground observations, remote sensing, and modeled data, this paper aimed to analyze the factors that led to this hazardous dust pollution event. This extraordinary episode was caused by a combination of several meteorological and topographic factors. There was a massive and relatively constant uplift of dust plumes from the northern Africa), combined with strong dry downslope winds behind mountain barriers in Central Europe, mainly the Alps. The steady, very good dispersion conditions with prevailing south-westerly wind direction of dry air masses at higher speeds, played a significant role. The combination of factors enabled high concentrations of Saharan dust to reach near-surface levels through temperature inversions or by aiding its dispersion. While the findings cannot be clearly quantified, they are a key source of information for the forecasting departments of the Czech Hydrometeorological Institute. These departments are authorised by the Czech Republic's Ministry of the Environment to issue warnings. The results provide comprehensive information about the available resources and data that can be monitored. This enables timely (faster) responses to unusual episodes. The results provide the arguments for necessary changes in Czech legislation regarding the issuance of warning signals, so-called smog situations and regulations.