Estimating natural nitrous oxide emissions from the Qinghai–Tibetan Plateau using a process-based model: Historical spatiotemporal patterns and future trends

•TRIPLEX-GHG model was validated and used to estimate the natural annual N2O fluxes from the Qinghai-Tibetan Plateau.•The total natural N2O emissions of the Qinghai-Tibetan Plateau showed a slight increasing trend from 1970 to 2017.•Temperature is a dominant factor for N2O emissions on the Qinghai-Tibetan Plateau.•Under the future warmer and wetter scenario, N2O emissions of the Qinghai-Tibetan Plateau will continue to increase. Fluctuations in natural nitrous oxide emissions (N2O) are not fully understood, especially on the Qinghai–Tibetan Plateau. In order to characterize the differences in historical N2O variations among different regions of the Qinghai-Tibetan Plateau and investigate how a warmer and wetter climate change would affect the N2O fluxes over the Qinghai-Tibetan Plateau, a process-based model (TRIPLEX-GHG) has been validated using 14 sites with annual N2O emission fluxes, and is used to estimate the spatiotemporal patterns of natural N2O fluxes, and predict its future trend for the Qinghai-Tibetan Plateau (the temperature increasing by 1.5 °C and the precipitation increasing by 10%). Considering the model performance evaluation indicators (R2=0.83, rRMSE=44.6%, PBIAS=7.18%), the performance of the model for simulating annual N2O fluxes is “moderate”. The estimated average total natural N2O emissions of the Qinghai-Tibetan Plateau from 1970 to 2017 were 0.313 Tg N yr−1, ranging from 0.305 Tg N yr−1 (1983) to 0.325 Tg N yr−1 (2006). The estimated total natural N2O emissions of the Qinghai-Tibetan Plateau slightly increased from 1970 to 2017, with a mean increase of 0.0002 Tg N yr−1. Between the 1970s and 2010s, most increases in N2O flux were observed in the northern and southeastern regions of the Qinghai-Tibetan Plateau. The area in which the rate of N2O released was greater than 15 µg N m−2 h−1 was mainly found in plateau temperate regions. Regions with relatively high temperatures released more N2O, which indicates that temperature is a dominant factor for N2O emissions in high-altitude regions. Natural N2O emissions of the Qinghai-Tibetan Plateau will increase up to 0.335 Tg N yr−1 (by approximately 6.13%) by 2050 if the climate continues to become warmer and wetter.