A 60 Year Record of Atmospheric Aerosol Depositions Preserved in a High‐Accumulation Dome Ice Core, Southeast Greenland

Abstract

Abstract The Southeastern Greenland Dome (SE‐Dome) has both a high elevation and a high accumulation rate (1.01 m we yr −1 ), which are suitable properties for reconstructing past environmental changes with a high time resolution. For this study, we measured the major ion fluxes in a 90 m ice core drilled from the SE‐Dome region in 2015 and present the records of annual ion fluxes from 1957 to 2014. From 1970 to 2010, the trend of nonsea‐salt (nss) SO 4 2− flux decreases, whereas that for NH 4 + increases, tracking well with the anthropogenic SO x and NH 3 emissions mainly from North America. The result suggests that these fluxes reflect histories of the anthropogenic SO x and NH 3 emissions. In contrast, the decadal trend of NO 3 − flux differs from the decreasing trend of anthropogenic NO x emissions. Although the cause of this discrepancy remains unclear, it may be related to changes in particle formation processes and chemical scavenging rates caused by an increase in sea salt and dust and/or a decrease in nssSO 4 2− . We also find a high average NO 3 − flux (1.13 mmol m −2 yr −1 ) in the ice core, which suggests a negligible effect from postdepositional NO 3 − loss. Thus, the SE‐Dome region is an excellent location for reconstructing nitrate fluxes. Over a decadal time scale, our NO 3 − flux record is similar to those from other ice cores in Greenland high‐elevation sites, suggesting that NO 3 − concentration records from these ice cores are reliable.