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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]

• CH 4 emissions in global supply chains during 2000–2012 were tracked. • Consumption-based CH 4 emissions of China/the EU showed an obvious increase/decrease trend in 2000–2012. • Growing amounts of CH 4 emissions were displaced globally via international trade. • The results support supply-chain-wised policy formulation to mitigate CH 4 emissions. Reduction of methane emissions (CH 4) plays an important role in addressing global climate change. Most previous studies have focused on the direct CH 4 emissions of economies, but overlooked the upstream CH 4 emissions along global supply chains induced by the final consumption of economies. Using a global multi-regional input-output analysis, this study aims to explore the evolution of CH 4 emissions embodied in international trade and final consumption in major economies during 2000–2012. The results show that China, the EU, USA, India and Brazil were the top five economies with high volumes of consumption-based CH 4 emissions from 2000 to 2012. In particular, China's consumption-based CH 4 emissions showed an observable growth trend, while the EU, the USA and Japan showed a downward trend. It's estimated that growing amounts of CH 4 emissions (i.e., the volume increase from 77.1 Mt in 2000 to 95.9 Mt in 2012) were transferred globally via international trade, primarily as exports from China, Russia and other large developing economies to consumers in major developed economies. Russia–EU, China–USA and China–EU formed the main bilateral trading pairs of embodied emission flows. Further analysis found that per capita consumption-based CH 4 emissions was closely related to their per capita GDP. Quantifying the CH 4 emissions embodied in trade and final demand of major economies can provide important basis for understanding economy-wide emission drivers to design global and regional CH 4 reduction scheme from a consumer perspective. [ABSTRACT FROM AUTHOR]

Globalization drives anthropogenic methane (CH 4) emissions from upstream to downstream agents through global supply chains. However, previous studies have overlooked the indirect CH 4 emissions enabled by primary suppliers. In this study, we use the Ghosh Multi-Regional Input-Output (MRIO) model and Structural Decomposition Analysis (SDA) to explore the temporal changes in global income-based CH 4 emissions and decompose the socioeconomic drivers. Our results show that global income-based CH 4 emissions increased by 17.21% from 2001 to 2014, with per capita primary inputs and technology being the two key drivers. Specifically, in China and India, income-based CH 4 emissions were mainly from agriculture, and input structure was responsible for restraining the growth in CH 4 emissions from their agricultural activities. On the other hand, service activities dominated the United States and the European Union, and production output structure was accountable for their emission growth related to service activities. To achieve global CH 4 emission mitigation, key sectors of major economies with high income-based CH 4 emissions should optimize their primary input structures, production output structure, and production technologies from the supply-side. It is crucial to reduce enabled CH 4 emissions in emerging economies, particularly in Asia, through the adjustment of primary input activities. [Display omitted] • Per capita primary inputs and technology dominated global CH 4 emission changes. • Income-based emissions decreased in West & Central Europe and the United States. • Agriculture and mining contributed to the high emissions in most emerging economies. • Production output structure accounted for the growth in service-enabled emissions. • Spatial heterogeneity of drivers of income-based CH 4 emissions was discussed. [ABSTRACT FROM AUTHOR]

Ensuring energy, water and food security is a core challenge as well as an opportunity to national sustainable development. This paper aims to perform an in-depth analysis on demand-driven energy, water and land resource requirements by Chinese economy 2012 and corresponding energy-water-land nexus relationships in its supply chains by using the input-output analysis and the structural path analysis. Results show that Agriculture and Light industry, mainly related to household consumption, are critical aggregated sectors for water and land requirements, in contrast to Heavy industry and Construction , which are related to investment for energy requirements. 15.41% of the total energy requirement, 44.18% of water and 58.64% of land can be attributed to the top 20 supply chain paths. The energy-water-land nexuses are explored by industrial sector, supply chain path and final demand category from the perspective of embodiment. On the final demand side, Agriculture , Light industry , Construction and Service are critical nexus sectors. Major sectoral nexus paths in terms of energy-land, energy-water, water-land, and energy-water-land nexuses are further identified. The energy-water-land nexus in China's supply chains reflect a strong dependence relationship of energy, water and land resource requirements, which then demonstrate essential intervention points of demand-side resource management. • Demand-driven energy, water and land requirements in China 2012 are revealed. • Embodied energy, water and land uses via domestic supply chains are traced. • The energy-water-land nexus are explored from the perspective of embodiment. • Critical sectors and supply chain paths of energy-water-land nexus are identified. [ABSTRACT FROM AUTHOR]