Variations in aerosol composition inferred from metal concentrations in the SE-Dome ice core, southeastern Greenland

The insoluble fraction of aerosols is typically quantified as the dust concentration, but its elemental composition remains poorly characterized, whereas the soluble fraction is commonly measured as the ion concentration. Analyzing the elemental composition of the insoluble fraction is crucial for identifying aerosol sources and understanding the factors that drive their variability. This study investigates temporal variations in total (i.e., soluble and insoluble) metal concentrations in an ice core from the southeastern dome of Greenland, covering the period from 1957 to 2014. Crustal elements (Al, non-sea salt (nss) Ca, and Fe) exhibited high concentrations during 1957–1975 (Period 1), low concentrations during 1976–1999 (Period 2), and a subsequent increase after 2000 (Period 3). The elemental ratios and seasonal flux patterns suggest that the aerosol sources and the factors controlling aerosol concentrations varied among the periods. Periods 1 and 2 are influenced by long-range transport of Asian mineral dust and anthropogenic emissions from North America and Europe, whereas Period 3 reflects growing contributions from local Greenland sources. Period 3 can be further divided into two periods: Period 3a (2000–2007) and Period 3b (2008–2014), based on differences in their compositions. During Period 3a, the enrichment in nssCa likely reflects increased inputs of soluble nssCa from coastal meltwater streams, along with additional contributions from the weathering of newly exposed carbonate rocks. In Period 3b, local Greenland soils became the dominant source, reducing the influence of Asian dust. Elevated Fe levels suggest additional contributions from volcanic soils, possibly from Iceland.