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Abstract Iron emissions from human activities, such as oil combustion and smelting, affect the Earth's climate and marine ecosystems. These emissions are difficult to quantify accurately due to a lack of observations, particularly in remote ocean regions. In this study, we used long‐term, near‐source observations in areas with a dominance of anthropogenic iron emissions in various parts of the world to better estimate the total amount of anthropogenic iron emissions. We also used a statistical source apportionment method to identify the anthropogenic components and their sub‐sources from bulk aerosol observations in the United States. We find that the estimates of anthropogenic iron emissions are within a factor of 3 in most regions compared to previous inventory estimates. Under‐ or overestimation varied by region and depended on the number of sites, interannual variability, and the statistical filter choice. Smelting‐related iron emissions are overestimated by a factor of 1.5 in East Asia compared to previous estimates. More long‐term iron observations and the consideration of the influence of dust and wildfires could help reduce the uncertainty in anthropogenic iron emissions estimates.
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Mapping the Iron Age in Southern Africa: Magnetometry at two Iron Age villages in Western Zambia
In recent years the use of near-surface geophysical survey – especially magnetometry – has been on the rise across sub-Saharan Africa, illustrating its utility at both large and/or built-up sites with stone architecture, as well as smaller and more ephemeral village sites in equatorial and sub-tropical regions of the continent. This article describes geophysical surveys and excavations at Nanga and Kanono, two Iron Age village sites in the Machile Valley, Western Zambia, undertaken between 2019 and 2022. Surveys allowed for detailed analyses of village layouts and showed the relationship between domestic areas and areas of iron production. Subsequent ground-truthing of both domestic and iron production areas elucidated differential spatial patterns of iron production stages (i.e., smelting and smithing) between village sites dating to between 800 and 1400, and allowed for the identification, excavation, and analyses of several Early Iron Age smelting furnaces.
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- Award ID(s):
- 2114147
- PAR ID:
- 10533005
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Journal of Archaeological Science
- Volume:
- 163
- Issue:
- C
- ISSN:
- 0305-4403
- Page Range / eLocation ID:
- 105937
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1016/j.jas.2024.105937
