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China is facing both serious water scarcity and climate change challenges simultaneously. There is an urgent need to identify the synergies between water conservation and greenhouse gas (GHG) emission mitigation. This paper aims to trace the embodied water uses and GHG emissions (i.e., CO 2 , CH 4 and N 2 O) via China's domestic supply chains in 2012 and to explore their common important paths for driving the water withdrawals and the emissions of GHGs using the environmentally-extended input-output analysis and the structural path analysis. The results show a significant coupling between the embodied water uses and the embodied emissions of CO 2 , CH 4 and N 2 O in the supply chains on a national scale. The water-GHG nexus relationships from the consumption-side are systematically revealed in terms of industrial sectors, final demands and supply chain paths. The top 20 nexus paths ranked by water together accounted for 37.40% of the national total water withdrawals. Ranked by GHGs, the proportions were 22.46% of the total GHG emissions. Synergies in saving water resources and mitigating the emissions of CO 2 , CH 4 and N 2 O can be achieved through controlling important supply chain paths and critical transmission sectors. The highly interlinked nature of water and climate change issues requires comprehensive solutions to reduce future freshwater and GHG emission needs to maintain sustained economic growth in China. Image 1 • We trace embodied water uses and GHG emissions in 2012 Chinese supply chains. • We develop Sankey diagrams to illustrate the water-GHG nexus relationships. • The top 20 paths ranked by water contributed 37.40% of the total water uses. • The top 20 paths ranked by GHG contributed 22.46% of the total GHG emissions. • Critical nexus sectors and paths are potential water and climate policy targets. [ABSTRACT FROM AUTHOR]

Abstract Agriculture is one of the most important sectors for global anthropogenic methane (CH 4) and nitrous oxide (N 2 O) emissions. While much attention has been paid to production-side agricultural non-CO 2 greenhouse gas (ANGHG) emissions, less is known about the emissions from the consumption-based perspective. This paper aims to explore the characteristics of agricultural CH 4 and N 2 O emissions of global major economies by using the latest emission data from the Food and Agriculture Organization Corporate Statistical Database (FAOSTAT) and the recently available global multi-regional input-output model from the World Input-Output Database (WIOD). The results show that in 2014, the 42 major economies together accounted for 60.7% and 65.0% of global total direct and embodied ANGHG emissions, respectively. The consumption-based ANGHG emissions in the US, Japan, and the EU were much higher than their production-based emissions, while the converse was true for Brazil, Australia, and India. The global-average embodied ANGHG emissions per capita was 0.7 t CO 2 -eq, but major developing countries such as China, India, Indonesia and Mexico were all below this average value. We find that the total transfer of embodied ANGHG emissions via international trade was 622.4 Mt CO 2 -eq, 11.9% of the global total. China was the largest exporter of embodied ANGHG emissions, while the US was the largest importer. Most developed economies were net importers of embodied emissions. Mexico-US, China-US, China-EU, China-Japan, China-Russia, Brazil-EU, India-EU and India-US formed the main bilateral trading pairs of embodied emission flows. Examining consumption-based inventories can be useful for understanding the impacts of final demand and international trade on agricultural GHG emissions and identifying appropriate mitigation potentials along global supply chains. Highlights • We explore agricultural CH 4 and N 2 O emission characteristics of 42 major economies. • Impacts of final demand and international trade on ANGHG emissions are evaluated. • 622.4 Mt CO 2 eq CH 4 and N 2 O emissions in 2014 were embodied in international trade. • Developed economies as net importers had high per capita emission requirements. [ABSTRACT FROM AUTHOR]