Human activities have drastically increased inputs of reactive nitrogen globally. Increased deposition of N onto forests may alleviate N limitation and thereby stimulated productivity and carbon (C) sequestration in forest aboveground woody biomass (AGWB), a stable C pool with long turn-over times. The associated reduction in atmospheric CO2 concentrations use represents a cooling effect of human N use that may partly offsets the warming effect of human-induced N2O emissions.The accompanying datasets give information on global spatial variation in the contribution of atmospherically deposited nitrogen (N) to carbon (C) sequestration in forest aboveground woody biomass, as well as the net climatic footprint of human N use resulting from the warming effect of N-induced direct and indirect N2O emissions on the one hand, and the cooling effect of N-induced C sequestration in forest aboveground woody biomass on the other.

Datasets include information on spatial variation in: Forest biomass C-N response (additional unit of carbon sequestration in forest aboveground woody biomass per unit of atmospheric N deposition; in kg C per kg N). Forest C-N response was predicted by a regression model that was derived from data from forest fertilization experimetns which measured biomass response to N addition. N-induced forest aboveground woody biomass C sequestration, which was derived by multiplying forest biomass C-N response with total N deposition to forests.* Net climate footprint of human N use, expressed as the ratio between additional C sequestration in forest aboveground woody biomass due to anthropogenic N deposition (as shown in Fig_2a, though Fig_2a considers total N deposition while here we only consider anthropogenic N deposition) and anthropogenic N2O emissions, both expressed as 100-year Global Warming Potential in Tg Ceq yr-1.For most variables, we provide the mean value as well as the 95% Confidence Inverval.Projection: WGS84Resolution: 0.5x0.5 degrees