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Abstract. Excessive anthropogenic nitrogen (N) inputs to the biosphere have disruptedthe global nitrogen cycle. To better quantify the spatial and temporalpatterns of anthropogenic N inputs, assess their impacts on thebiogeochemical cycles of the planet and the living organisms, and improvenitrogen use efficiency (NUE) for sustainable development, we have developeda comprehensive and synthetic dataset for reconstructing the History ofanthropogenic Nitrogen inputs (HaNi) to the terrestrial biosphere. The HaNi datasettakes advantage of different data sources in a spatiotemporally consistentway to generate a set of high-resolution gridded N input products from thepreindustrial period to the present (1860–2019). The HaNi dataset includes annual ratesof synthetic N fertilizer, manure application/deposition, and atmospheric Ndeposition on cropland, pasture, and rangeland at a spatial resolution of5 arcmin × 5 arcmin. Specifically, the N inputs are categorized, according to the Nforms and land uses, into 10 types: (1) NH4+-N fertilizer applied to cropland,(2) NO3--N fertilizer applied to cropland, (3) NH4+-N fertilizer applied to pasture,(4) NO3--N fertilizer applied to pasture, (5) manure N application oncropland, (6) manure N application on pasture, (7) manure N deposition onpasture, (8) manure N deposition on rangeland, (9) NHx-N deposition, and(10) NOy-N deposition. The total anthropogenic N (TN) inputs to globalterrestrial ecosystems increased from 29.05 Tg N yr−1 in the 1860s to267.23 Tg N yr−1 in the 2010s, with the dominant N source changing fromatmospheric N deposition (before the 1900s) to manure N (in the 1910s–2000s)and then to synthetic fertilizer in the 2010s. The proportion of syntheticNH4+-N in fertilizer input increased from 64 %in the 1960s to 90 % in the 2010s, while synthetic NO3--N fertilizerdecreased from 36 % in the 1960s to 10 % in the 2010s. Hotspots of TNinputs shifted from Europe and North America to East and South Asia duringthe 1960s–2010s. Such spatial and temporal dynamics captured by the HaNidataset are expected to facilitate a comprehensive assessment of the coupledhuman–Earth system and address a variety of social welfare issues, such as theclimate–biosphere feedback, air pollution, water quality, and biodiversity. Thedata are available at https://doi.org/10.1594/PANGAEA.942069(Tian et al., 2022). 

Abstract Carbon fluxes at the land‐atmosphere interface are strongly influenced by weather and climate conditions. Yet what is usually known as “climate extremes” does not always translate into very high or low carbon fluxes or so‐called “carbon extremes.” To reveal the patterns of how climate extremes influence terrestrial carbon fluxes, we analyzed the interannual variations in ecosystem carbon fluxes simulated by the Terrestrial Biosphere Models (TBMs) in the Inter‐Sectoral Impact Model Intercomparison Project. At the global level, TBMs simulated reduced ecosystem net primary productivity (NPP; 18.5 ± 9.3 g C m⁻² yr⁻¹), but enhanced heterotrophic respiration (Rh; 7 ± 4.6 g C m⁻² yr⁻¹) during extremely hot events. TBMs also simulated reduced NPP (60.9 ± 24.4 g C m⁻² yr⁻¹) and reduced Rh (16.5 ± 11.4 g C m⁻² yr⁻¹) during extreme dry events. Influences of precipitation extremes on terrestrial carbon uptake were larger in the arid/semiarid zones than other regions. During hot extremes, ecosystems in the low latitudes experienced a larger reduction in carbon uptake. However, a large fraction of carbon extremes did not occur in concert with either temperature or precipitation extremes. Rather these carbon extremes are likely to be caused by the interactive effects of the concurrent temperature and precipitation anomalies. The interactive effects showed considerable spatial variations with the largest effects on NPP in South America and Africa. Additionally, TBMs simulated a stronger sensitivity of ecosystem productivity to precipitation than satellite estimates. This study provides new insights into the complex ecosystem responses to climate extremes, especially the emergent properties of carbon dynamics resulting from compound climate extremes.