1. Global nitrous oxide budget (1980–2020)
- Author
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Tian, Hanqin, Pan, Naiqing, Thompson, Rona, Canadell, Josep G., Suntharalingam, Parvadha, Regnier, Pierre, Davidson, Eric, Prather, Michael, Ciais, Philippe, Muntean, Marilena, Pan, Shufen, Winiwarter, Wilfried, Zaehle, Sönke, Zhou, Feng, Jackson, Robert, Bange, Hermann W., Berthet, Sarah, Bian, Zihao, Bianchi, Daniele, Bouwman, A.F., Buitenhuis, Erik, GEOFFREY, DUTTON, Hu, Minpeng, Ito, Akihiko, Jain, Atul, Jeltsch-Thömmes, Aurich, Joos, Fortunat, Kou-Giesbrecht, Sian, Krummel, Paul, Lan, Xin, Landolfi, Angela, Lauerwald, Ronny, Li, Ya, Lu, Chaoqun, Maavara, Taylor, Manizza, Manfredi, Millet, Dylan, Mühle, Jens, Patra, Prabir K., Peters, Glen, Qin, Xiaoyu, Raymond, Peter, Resplandy, Laure, Rosentreter, Judith A., Shi, Hao, Sun, Qing, Tonina, Daniele, Tubiello, Francesco Nicola, Werf, Guido van der, Vuichard, Nicolas, Wang, Junjie, Wells, Kelley C., Western, Luke, Wilson, Chris, Yang, Jia, Yao, Yuanzhi, You, Yongfa, Zhu, Qing, Tian, Hanqin, Pan, Naiqing, Thompson, Rona, Canadell, Josep G., Suntharalingam, Parvadha, Regnier, Pierre, Davidson, Eric, Prather, Michael, Ciais, Philippe, Muntean, Marilena, Pan, Shufen, Winiwarter, Wilfried, Zaehle, Sönke, Zhou, Feng, Jackson, Robert, Bange, Hermann W., Berthet, Sarah, Bian, Zihao, Bianchi, Daniele, Bouwman, A.F., Buitenhuis, Erik, GEOFFREY, DUTTON, Hu, Minpeng, Ito, Akihiko, Jain, Atul, Jeltsch-Thömmes, Aurich, Joos, Fortunat, Kou-Giesbrecht, Sian, Krummel, Paul, Lan, Xin, Landolfi, Angela, Lauerwald, Ronny, Li, Ya, Lu, Chaoqun, Maavara, Taylor, Manizza, Manfredi, Millet, Dylan, Mühle, Jens, Patra, Prabir K., Peters, Glen, Qin, Xiaoyu, Raymond, Peter, Resplandy, Laure, Rosentreter, Judith A., Shi, Hao, Sun, Qing, Tonina, Daniele, Tubiello, Francesco Nicola, Werf, Guido van der, Vuichard, Nicolas, Wang, Junjie, Wells, Kelley C., Western, Luke, Wilson, Chris, Yang, Jia, Yao, Yuanzhi, You, Yongfa, and Zhu, Qing
- Abstract
Nitrous oxide (N2O) is a long-lived potent greenhouse gas and stratospheric ozone-depleting substance that has been accumulating in the atmosphere since the preindustrial period. The mole fraction of atmospheric N2O has increased by nearly 25 % from 270 ppb (parts per billion) in 1750 to 336 ppb in 2022, with the fastest annual growth rate since 1980 of more than 1.3 ppb yr−1 in both 2020 and 2021. According to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC AR6), the relative contribution of N2O to the total enhanced effective radiative forcing of greenhouse gases was 6.4 % for 1750–2022. As a core component of our global greenhouse gas assessments coordinated by the Global Carbon Project (GCP), our global N2O budget incorporates both natural and anthropogenic sources and sinks and accounts for the interactions between nitrogen additions and the biogeochemical processes that control N2O emissions. We use bottom-up (BU: inventory, statistical extrapolation of flux measurements, and process-based land and ocean modeling) and top-down (TD: atmospheric measurement-based inversion) approaches. We provide a comprehensive quantification of global N2O sources and sinks in 21 natural and anthropogenic categories in 18 regions between 1980 and 2020. We estimate that total annual anthropogenic N2O emissions have increased 40 % (or 1.9 Tg N yr−1) in the past 4 decades (1980–2020). Direct agricultural emissions in 2020 (3.9 Tg N yr−1, best estimate) represent the large majority of anthropogenic emissions, followed by other direct anthropogenic sources, including fossil fuel and industry, waste and wastewater, and biomass burning (2.1 Tg N yr−1), and indirect anthropogenic sources (1.3 Tg N yr−1) . For the year 2020, our best estimate of total BU emissions for natural and anthropogenic sources was 18.5 (lower–upper bounds: 10.6–27.0) Tg N yr−1, close to our TD estimate of 17.0 (16.6–17.4) Tg N yr−1. For the 2010–2019 period, the annual BU decad
- Published
- 2024