Wanjun Wang, Wei-Qiang Chen*, Zhou-Wei Diao, Luca Ciacci, Leila Pourzahedi, Matthew J. Eckelman, Yi Yang, and Lei Shi*

Environmental Science & Technology , 2021 55 (10), 7102-7112

DOI: 10.1021/acs.est.0c08836

Abstract：

Disputes around trade inequality have been growing over the last 2 decades, with different countries claiming inequality in different terms including monetary deficits, resource appropriation and degradation, and environmental emission transfer. Despite prior input–output-based studies analyzing multidimensionaltrade consequences at the sector level, there is a lack of bottom-up studies that uncover the complexity of trade imbalances at the product level. This paper quantifies four types of flows, monetary, resource, embodied energy use, and embodied greenhouse gas (GHG) emissions, resulting from aluminumtrade for the four economies with the highest aluminumtrade, that is, the United States, China, Japan, and Australia. Results show that the United States has a negative balance in monetary flows but a positive balance in resource flows, embodied energy use, and GHG emissions. China has a positive balance in monetary and resource flows but a negative balance in embodied energy use and GHG emissions. Japan has a positive balance in all flows, while Australia has a negative balance in all flows. These heterogeneous gains and losses along the globalleaders of aluminumtrade arise largely from their different trade structures and the heterogeneities of price, energy use, and GHG emission intensities of aluminum products; for example, Japan mainly imports unwrought aluminum, and its quantity is 3 times that of the exported semis and finished aluminum-containing products that have similar energy and GHG emission intensities but 20 times higher prices, while Australia mainly exports bauxite and alumina that have the lowest prices, the quantity of which is 25 times that of imported semis and finished products. This study suggests that resource-related trade inequalities are not uniform across economic and environmental impacts and that trade policies must be carefully considered from various dimensions.

Key words：

aluminum, trade inequality, embodied energy, embodied GHG emissions, material flow analysis, industrial ecology