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<p>The application of nitrogenous fertilisers to agricultural soils is a major source of anthropogenic <span class="inline-formula">N₂O</span> emissions. Reducing the nitrogen (N) footprint of agriculture is a global challenge that depends, among other things, on our ability to quantify the <span class="inline-formula">N₂O</span> emission intensity of the world's most widespread and productive agricultural systems. In this context, biogeochemistry (BGC) models are widely used to estimate soil <span class="inline-formula">N₂O</span> emissions in agroecosystems. The choice of spatial scale is crucial because larger-scale studies are limited by low input data precision, while smaller-scale studies lack wider relevance. The robustness of large-scale model predictions depends on preliminary and data-demanding model calibration/validation, while relevant studies often omit the performance of output uncertainty analysis and underreport model outputs that would allow a critical assessment of results. This study takes a novel approach to these aspects. The study focuses on arable eastern Scotland – a data-rich region typical of northwest Europe in terms of edaphoclimatic conditions, cropping patterns and productivity levels. We used a calibrated and locally validated BGC model to simulate direct soil <span class="inline-formula">N₂O</span> emissions along with <span class="inline-formula">NO₃</span> leaching and crop N uptake in fields of barley, wheat and oilseed rape. We found that 0.59&thinsp;% (<span class="inline-formula">±0.36</span>) of the applied N is emitted as <span class="inline-formula">N₂O</span> while 37&thinsp;% (<span class="inline-formula">±6</span>) is taken up by crops and 14&thinsp;% (<span class="inline-formula">±7</span>) is leached as <span class="inline-formula">NO₃</span>. We show that crop type is a key determinant of <span class="inline-formula">N₂O</span> emission factors (EFs) with cereals having a low (mean <span class="inline-formula">EF&lt;0.6</span>&thinsp;%), and oilseed rape a high (mean <span class="inline-formula">EF=2.48</span>&thinsp;%), <span class="inline-formula">N₂O</span> emission intensity. Fertiliser addition was the most important <span class="inline-formula">N₂O</span> emissions driver suggesting that appropriate actions can reduce crop <span class="inline-formula">N₂O</span> intensity. Finally, we estimated a 74&thinsp;% relative uncertainty around <span class="inline-formula">N₂O</span> predictions attributable to soil data variability. However, we argue that higher-resolution soil data alone might not suffice to reduce this uncertainty.</p>