Roulin Khondoker The Team

Isotopic and Element Characterisation of Potential Sources of Aerosols entering the

South Atlantic Ocean

Roulin Khondoker

The TeamDominik Weiss, Tina van de Flierdt, Mark Rehkamper, Alex Baker, Rosie Chance

roulin khondoker

Say: Introduce topic, myself and say who my supervisors are. Maybe include working closely with Rosie, Alex on the aerosol collection and analysis procedure, and work with Emma and Stas on multielement characterisation?

PhD ProjectPhD• 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 & ObjectivesAimsCharacterise 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

Types of Sources

AnthropogenicUrban Aerosol Traffic emissions

Road dustFuel (e.g. gasoline, coal)Lichens

Industrial Emission Industrial plant (e.g. smelters) and factory emissionsCoal (e.g. fuel burning at power plants)

NaturalNatural Aerosol Aeolian/windblown dust

Desert dustVolcanic dustLichen

Volcanic Material AshDebrisSoilVolcanic Rock

Natural Sediment Rock (e.g. rock type besides volcanic)SoilSandLoessRiverbed sediment

Sea Spray

Important Emissions

Sao Paulo & Rio de Janeiro

Patagonia

Andes

Buenos Aires

Namibia

South Africa

Anthropogenic

Urban Aerosol Traffic emissionsRoad dustFuelLichens

Industrial Emission Industrial plant and factory emissionsCoal

Natural

Natural Aerosol Aeolian/windblown dustDesert dustVolcanic dustLichen

Volcanic Material AshDebrisSoilVolcanic Rock

Natural Sediment Rock (e.g. rock type besides volcanic)SoilSandLoessRiverbed sediment

Sea Spray

roulin khondoker

Say: From previous studies, modelling and satellite imaging the major winds bringing emissions to across the SAO originate from S America (Patagonia, Andes, Brazil) and Southern Africa (potentially regions of South Africa, Namibia and the Kalahari Desert).

Sample CollectionRegions Samples & Data were Collected from

Samples Collected

South America Type of Source Southern Africa Type of SourceBuenos AiresSao Paulo

Patagonia

Andes

Urban Aerosol

Volcanic MaterialNatural SedimentVolcanic Material

Johannesburg Urban Aerosol

Data CollectedBrazil Columbia Ecuador

Chile

Argentina

Urban Aerosol

Urban AerosolNatural SedimentVolcanic Material

Urban AerosolsNatural AerosolNatural SedimentVolcanic Material

Namibia

South Africa

Kalahari Desert

Natural AerosolVolcanic MaterialNatural Sediment

Urban aerosolIndustrial EmissionNatural Aerosol

Natural Aerosol

roulin khondoker

roulin khondoker

Say: For this and next slide - Describe briefly the regions samples have been collected from and sample types (aerosols, road dusts etc), regions Pb and Nd IR have been collected from and maybe mention some literature/authors data taken from. For samples, hotplate digested them, used ICP-AES and MS for ME and TM characterisation and MC-ICP-MS for IR. As Zn IR for sources is limited, this study produces a novel database of Zn data. It is then important that I gain more samples from at least Southern Africa

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 DatabasePb, Nd, Zn Isotopic Ratio DatabaseMultielement Concentration Database

roulin khondoker

Show snippet of spreadsheetDatabase of source data isotopic dataDatabase of trace metal total concentration database

Source Characterisation: Pb

roulin khondoker

Say: I present Pb IR of source data, literature and samples analysed thus far, figure shows distinct Pb IR characterisation between countries/regions, describe the type of samples each country shows (most are of one type) and hence this figure also shows one can fairly distinguish between natural rock, anthropogenic and volcanic sources of different regions across S America


roulin khondoker

Say: Discuss that there's a fair difference in Pb IR for the two countries and source type. Discuss that when combine the S America and S Africa figures together it appears both continents overlap and S America anthropogenic sources have similar Pb IR to S Africa natural, and vise versa, discuss it then becomes important to consider the emission importance...when I go to analyse the provenance of aerosols from across the 40 S transect of SAO I must consider which emissions are more important, those from S America, or those from S Africa.


Southern Africa

South America

Source Characterisation: Nd

-30 -25 -20 -15 -10 -5 0 5 10

εNd

Between Port Elizabeth to Cape Town

AndesBetween Patagonia

to B Aires

2σ

Urban Aerosol

Natural Aerosol

South America

Southern Africa

Natural Aerosol

Urban AerosolBuenos Aires

Johannesburg

Patagonia

roulin khondoker

Say: Diplay eNd data, discuss if any clear characterisation of sources by region or source type

Source Characterisation: Zn

-0.8 -0.6 -0.4 -0.2 0.0 0.2 0.4 0.6 0.8 1.0

δ66/64 ZnLyon (‰)

Igneous

Anthropogenic

Industrial Emission

Urban Aerosol

Volcanic Material

F Larner, M Rehkamper (2012) Evaluation of Stable Isotope Tracing for ZnO Nanomaterials New Constraints from High Precision Isotope Analyses and Modeling

2σ

roulin khondoker

Say: Diplay Zn 66 data compared with literature data for other source regions and types, discuss if any clear characterisation of sources by region or source type. Compared with Zn 66 data of literature shows my data fit typical 66 data for source type, not necessarily distinguishes source region.

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

roulin khondoker

refine these conclusions: be systemmatic n logical with classification of sources, finish with a table of how u can id what source e.g. i can identify dust SAmer vs SAfr using Nd isotopes, i can id diff countries in SAMER using Pb isotopes i.e. Brazil =, Pat =...,SAFR Nd=

Thank you

Roulin Khondoker The Team

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