Increasing worldwide demand for beef products promotes international beef trade. Cattle raising and beef products as significant sources of methane (CH 4 ) emissions have received widespread concerns. However, the factors driving CH 4 emissions embodied in the global beef trade have not been quantified. Here, we evaluate international beef trade-induced CH 4 emissions and assess the contribution of the five driving factors to changes in CH 4 emissions embodied in the beef trade from 2000 to 2018. We show that driven by increasing population and meat demands, the global beef trade-induced CH 4 emissions increased continuously in the past two decades, with total emissions of 9337.3 Gg in 2018. The drivers that could potentially reduce trade-related emissions are emission intensities in beef exporting countries and beef importing countries' selections of their beef suppliers. Together, these two driving factors reduced CH 4 emissions by 923.5 Gg from 2012 to 2018. Results suggest that efforts should be made to reduce the emission intensity via improving cattle feed and feeding practices in beef exporting countries. Beef importing countries could also contribute to CH 4 emission reduction by selecting those beef exporting countries with low emission intensities.

 Agricultural emission in India is an important sector contributing to the local and regional black carbon contamination and climate forcing  Estimated regional black carbon direct radiative forcing in India showed a fourfold increase during the operation of the Green Revolution  The contribution of India's intensive agriculture associated with Green Revolution to global black carbon climate forcing grew significantly Accepted ArticleThis article has been accepted for publication and undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record. Please cite this article as

Urbanization perturbs air pollutants from a dynamic and thermodynamic perspective, which has inspired extensive investigations in China due to rapid urban land expansion in the past four decades. However, knowledge gaps remain in the long-term and nationwide responses to air pollutants to urbanization. The evolution of tropospheric ozone associated with urban land expansion across China was assessed from 1980 to 2017 using a coupled WRF-Chem model based on a recently updated land use change (LUC) data set. The results revealed that urban-land expansion drove growing ozone trends for this period and contributed about 3−9% to its summer maximum concentrations during the 2010s in major urban agglomerations across China. The association between a long-term change in summer O 3 concentrations and LUC after excluding the effect of precursor emissions and meteorological conditions and causes of interannual (short-term) variations in O 3 concentrations induced by urban-land expansion were also explored by examining the relationships between ozone fluctuations and meteorological variables.

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Summary The bioaccumulation of polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs), known as dioxins, in fatty meat is one of primary pathways of entry into the human body, but levels of human exposure to dioxins in fatty meat subject to global trade are unknown. We show high dioxin estimated dietary intake (EDI) via pork consumption in Europe, the United States, and China, owing to stronger dioxin environmental contamination and high pork consumption in these countries. The dioxin risk transfer embodied in pork trade is mostly significant in high-latitude countries and regions of Canada, Russia, and Greenland because these regions with low dioxin environmental levels import large amounts of pork meat from more severely dioxin-contaminated Europe and the United States. We demonstrate that global pig feed trading decreases the exposure of pork consumers to dioxins via the import of feed from countries with low dioxin environmental contamination by pig breeding countries.