How does the local wind field control the aerosol distribution in coastal Dronning Maud Land?

• Main Authors: Schmidt, Katrin, Wegner, Anna, Weller, Rolf, Fischer, Hubertus, Bigler, M.
• Format: Conference Object
• Language: unknown
• Published: 2011
• Subjects: Antarc*; Antarctica; Dronning Maud Land
• Online Access: https://epic.awi.de/id/eprint/23480/; https://epic.awi.de/id/eprint/23480/1/Sch2011b.pdf; https://hdl.handle.net/10013/epic.36323; https://hdl.handle.net/10013/epic.36323.d001

Atmospheric circulation patterns and chemical concentrations in firn cores are highly related to each other. Atmospheric winds transport aerosols like sea salt and mineral dust over the globe and redistribute them. Because of this, it is possible to reconstruct atmospheric circulation bringing aerosol to Antarctica by analyzing chemical impurities in firn and ice. With these analyses, the gap caused by sparse atmospheric measurements can be filled and this knowledge can then be used to improve the understanding of local and global circulation patterns.Due to a very high accumulation rate (~600 kg/m²*a), coastal Dronning Maud Land (CDML) is a perfect site to conduct these studies.Here, the upper 6m of two firn cores drilled on Halvfaryggen and Sörasen (covering the time interval from 2002- 2007) were analyzed on ionic concentrations. This data was then contrasted to measurements from the air chemistry laboratories at Neumayer (NM) and Kohnenstation (KS), and synoptic measurements from automatic weather stations (distributed in CDML and at NM).The analyses show very different results: Sea salt ions (e.g. Na+) are higher correlated to ions measured in aerosol samples at the air chemistry laboratory at KS than to the one located at NM. In contrast, ions representing mineral dust (e.g. nss-Ca2+) only have a weak correlation over the whole area and time period. Accordingly, the deposition of aerosol is highly dependent on its origin and the topography in coastal Antarctica suggesting different transport pathways for sea level and higher altitude sites.