Assessment of sea salt and mineral dust contributions to PM10 in NW Germany using tracer models and positive matrix factorization

► PM10 shares by sea salt and mineral dust are quantified. ► Various mass closure approaches and PMF results are compared. ► Tracer models are more suitable than PMF to quantify natural contributions. ► Methodologies to routinely monitor the source contributions are proposed. ► For NW Germany sea salt has a minor effect on daily PM10 limit exceedances.