Table of contents
Chapter 1: Introduction and Outline ... 11
1.1 Dust impact on the Earth system and human health ... 12
1.1.1 Dust and Radiative forcing 1.1.2 Impacts of dust deposition on ocean biogeochemistry and the Carbon cycle 1.1.3 Dust and Human health 1.2 Dust sources, transportation and deposition ... 17
1.3 Methods to characterise and trace dust sources ... 18
1.3.1 Particle-scale analysis 1.3.2 Isotopic analyses 1.3.3 Rare Earth Elements (REE) 1.4 Atmospheric circulation and weather conditions around Antarctica... 21
1.4.1 General setting of the Antarctica 1.4.2 Meteorology at the Princess Elisabeth Antarctica (PEA) station 1.5 Geological context of the Sør Rondane, PEA area ... 24
1.6 Context and Objectives ... 27
1.6.1 Thesis Outline Chapter 2: First multi-isotopic (Pb-Nd-Sr-Zn-Cu-Fe) characterization of dust reference materials (ATD and BCR-723): a multi-column chromatographic method optimized to trace mineral and anthropogenic dust sources ... 35
2.1 Introduction ... 37
2.2 Experimental methods ... 38
2.2.1 Reagents, rocks, dust reference materials and dust samples 2.2.2 Dissolution 2.2.3 New multi-element separation scheme for dust isotopic signature 2.2.4 Isotopic analyses 2.3 Results and discussion: Validation scheme implemented ... 47
2.3.1 Sample ashing and dissolution 2.3.2 Chromatography: analyte separation and recovery 2.3.3 Results of multi-isotopic analyses and estimation of measurement uncertainties 2.4 Conclusions ... 60
2.5 Supplementary information ... 66
Chapter 3: Chemical and morphological characterization at the particle scale of East-Antarctic mineral dust samples along a 250 km inland-coast transect ... 71
3.1 Objectives and Introduction ... 72
3.2 Sampling sites and materials ... 72
3.3 Analytical Methodology ... 75
3.3.1 Sample Preparation for SEM-EDS analyses 3.3.2 Instrumental settings 3.3.3 Data Compilation - Matlab script 3.4 Results ... 79
3.4.1 Snow versus Sigma-2 samples
3.4.2 Precision – Accuracy - Reproducibility 3.4.3 Grain-Size Distribution
3.4.4 Shape
3.4.5 Chemical Composition
3.4.6 Distribution and variability between coastal and inland samples
3.5 Discussion ... 87
3.5.1 Sampling considerations and sample selection 3.5.2 Spatial and temporal variations along the coast-inland transect 3.6 Conclusion and Perspectives ... 89
Chapter 4: Identifying and quantifying dust sources in Northeast Antarctica using REE ... 93
4.1 Introduction ... 95
4.2 Methods ... 96
4.3 Results and discussion ... 98
4.4 Supplementary information ... 102
4.4.1 Sampling and processing 4.4.2 REE analysis 4.4.3 Compilation of the dust source regions and REE model inputs 4.4.4 REE statistical analysis 4.4.5 Atmospheric dispersion and back trajectory modeling Chapter 5: First high-resolution reconstruction and quantification of dust provenance in East Antarctica over the last glacial-interglacial transition ... 121
5.1 introduction ... 123
5.2 Description of correlation-based analysis of dust provenance in ice cores ... 124
5.3 Results ... 128
5.3.1 Uncertainty and statistical significance of correlation 5.3.2 Evolution of dust provenance in EDML and EDC ice cores 5.4 Discussion ... 136
5.4.1 New-Zealand 5.4.2 South Central Western Argentina 5.4.3 Patagonia 5.4.4 Puna-Altiplano Plateau 5.4.5 Southern Africa 5.4.6 Australia 5.5 Conclusions and perspectives ... 146
Chapter 6: Thesis conclusions and perspectives ... 153
Annexe 1: Elevated dust deposition in Tierra del Fuego (Chile) resulting from Neoglacial Darwin Cordillera glacier fluctuations ... 159
Annexe 2: Importance of Southern African dust to East Antarctica interglacial records ... 171
Annexe 3: Mineral phosphorus drives glacier algal blooms on the Greenland Ice Sheet ... 189
Appendix ... 237
Appendix A: Sør Rondane Rocks’ images ... 238
Appendix B: MatLab Script – SEM-EDS data mineralogical classification ... 239
Appendix C: MatLab Script – Statistical approach for determining and quantifying dust source using REE patterns ... 248
