160 likes | 169 Views
This PhD project aims to characterise aerosol sources entering the South Atlantic Ocean, distinguishing between anthropogenic and natural sources through isotopic and elemental analysis. The study focuses on South America and Southern Africa, collecting samples and creating a database for trace metals and isotopic ratios of potential sources.
E N D
Isotopic and Element Characterisation of Potential Sources of Aerosols entering the South Atlantic Ocean Roulin Khondoker The Team Dominik Weiss, Tina van de Flierdt, Mark Rehkamper, Alex Baker, Rosie Chance
PhD Project PhD • The Importance of Anthropogenic Vs. Natural Sources of Aerosols into the South Atlantic Ocean (SAO) PhD Aims • Characterise key aerosol sources in South America and Southern Africa • Characterise aerosols collected from D357 and JC068 cruises • Make interpretations on anthropogenic vs. natural trace metal aerosol sources in the South Atlantic Ocean
Outline of Talk • Aims & Objectives • Materials & Methods • Results • Conclusions
Aims & Objectives Aims Characterise the major ion, trace metal and REEs concentration and isotopic ratios (of Pb, Nd and Zn) of potential sources of aerosols entering the SAO and identify characteristic sources for the proxies Objectives • Identify important emission regions that transport aerosols to the SAO • Collect data and samples of potential sources of these emissions • Create a database of Pb, Nd and Zn isotope data and element data of these sources • Identify anthropogenic vs. natural sources
Important Emissions Sao Paulo & Rio de Janeiro Namibia Andes South Africa Buenos Aires Patagonia
Sample Collection • Collected and analysed/will analyse for : - • Total concentration of major ions (Al, Ca, Fe, K, Mg, Na) on ICP-AES • Total concentration of trace metals and REEs (Cu, Co, La, Mn, Nd, Ni, Pb, Sn, Zn, Y) on ICP-MS • Pb, Nd and Zn isotopic ratios on MC-ICP-MS • Pb & Nd data collected, but limited Zn data for Southern Africa sources (anthropogenic and natural) • Important to collect more samples from at least Southern Africa
Source Database Multielement Concentration Database Pb, Nd, Zn Isotopic Ratio Database
Source Characterisation: Pb Southern Africa South America
Source Characterisation: Nd South America Buenos Aires Urban Aerosol Natural Aerosol Patagonia Southern Africa Natural Aerosol Johannesburg Urban Aerosol
Source Characterisation: Zn 2σ Igneous Anthropogenic Industrial Emission Urban Aerosol Volcanic Material δ66/64ZnLyon (‰) F Larner, M Rehkamper (2012) Evaluation of Stable Isotope Tracing for ZnONanomaterials New Constraints from High Precision Isotope Analyses and Modeling
Conclusion • Anthropogenic Vs. Natural sources between South America and Southern Africa can be characterised using Pb isotopic ratios • Anthropogenic sources between South America and Southern Africa can be characterised by Nd isotopic ratios • Possibly, natural sources between South America and Southern Africa can be characterised by Nd isotopic ratios • Zn identifies some variation between anthropogenic vs. natural sources but unable to distinguish between region of origin yet as dataset is limited • Further work to be carried out to be able to use multielement data to characterise sources