Nitrate records of a shallow ice core from East Antarctica: Atmospheric processes, preservation and climatic implications

• Published in: Holocene (Sevenoaks) Vol. 21; no. 2; pp. 351 - 356
• Main Authors: Laluraj, C.M., Thamban, M., Naik, S.S., Redkar, B.L., Chaturvedi, A., Ravindra, R.
• Format: Journal Article
• Language: English
• Published: London, England SAGE Publications 01-03-2011; Sage Publications; Sage Publications Ltd
• Subjects: Aerosols; Climate change; Earth sciences; Earth, ocean, space; Exact sciences and technology; Geochemistry; Glaciers; Ions; Isotope geochemistry; Isotope geochemistry. Geochronology; Isotopes; Marine and continental quaternary; Nitrates; Surficial geology; polar regions; Antarctica; East Antarctica; Antarctica, East Antarctica; oxygen isotope; East Antarctica; nitrate; ion induced nucleation; sulphate; solar activity; stable isotopes; upper Holocene; O-18/O-16; Quaternary; solar radiation; ice; sulfates; upper Quaternary; nitrates; paleoclimate; drill cores; Be-10; Cenozoic; Phanerozoic; Holocene; high resolution
• ISSN: 0959-6836; 1477-0911
• DOI: 10.1177/0959683610374886

High-resolution records of nitrate (NO3
−), oxygen isotope (δ 18O) and non-sea salt sulphate (nssSO4
2− ) were studied using an ice core collected from central Dronning Maud Land in East Antarctica to identify the influence of environmental variability on accumulation of NO3
− over the past 450 years. The results confirmed that multiple processes were responsible for the production and preservation of NO3
− in Antarctic ice. Correlation between NO3
− and nssSO4
2− peaks revealed that sulphate aerosols released during major volcanic eruptions might have activated the production of nitric acid, which was scavenged by ion-induced nucleation in polar ice sheets. The correlation between the nitrate and δ18 O records further suggest that enhanced NO3
− preservation in the ice occurred during periods of lower atmospheric temperature. Major shifts in the NO3
− record of the ice core presently studied and its comparison with 10Be record from a core collected from South Pole suggest that a reduction in solar activity influenced the NO3
− accumulation in Antarctica through enhanced production of odd nitrogen species.