Saharan Dust Across the Wider Mediterranean Region, Part B: NAO and ENSO Modulation of Dust-Transport Variability

This study investigates the influence of large-scale climate modes on Mediterranean dust-transport variability using a newly developed Saharan Dust Flux Transport Index (SDFTIbase) for 2003–2024. Monthly and seasonal correlations show that NAO–SDFTIbase associations reach r = 0.35–0.55 across sub-regions, whereas ENSO–SDFTIbase correlations remain weaker (r = 0.10–0.25). Running correlations reveal pronounced non-stationarity, fluctuating between −0.4 and +0.6, while wavelet coherence exceeds 0.5 at 2–4-year periods during episodic teleconnection events. NAO exerts its strongest influence at sub-annual scales (0.15–0.5 years), whereas ENSO modulates dust transport primarily at interannual scales (1–3 years). Teleconnection strength is regionally heterogeneous: WestMed and EastMed exhibit the most persistent coupling, CentMed shows weak sensitivity, and BalBSea displays intermediate behaviour. NAO produces near-immediate dust-transport responses, while ENSO often leads dust-transport variability. These results provide a multi-scale dynamical framework linking Atlantic and Indo-Pacific climate variability to Mediterranean dust-transport pathways and highlight the importance of teleconnection-based diagnostics for regional climate assessment.