This study developed a next-generation atmospheric aerosol/chemistry-climate model, the BCC_AGCM_CUACE2.0. Then, the performance of the model for nitrate was evaluated, and the nitrate direct radiative forcing (DRF) and effective radiative forcing (ERF) due to aerosol-radiation interactions were simulated for the present day (2010), near-term future (2030), and middle-term future (2050) under the Representative Concentration Pathway 4.5, 6.0, and 8.5 scenarios relative to the preindustrial era (1850). The model reproduced the distributions and seasonal changes in nitrate loading well, and simulated surface concentrations matched observations in Europe, North America, and China. Current global mean annual loading of nitrates was predicted to increase by 1.50 mg m(-2) relative to 1850, with the largest increases occurring in East Asia (9.44 mg m(-2)), Europe (4.36 mg m(-2)), and South Asia (3.09 mg m(-2)). The current global mean annual ERF of nitrates was -0.28 W m(-2) relative to 1850. Due to global reductions in pollutant emissions, the nitrate ERF values were predicted to decrease to -0.17, -0.20, and -0.24 W m(-2) in 2030 and -0.07, -0.18, and -0.19 W m(-2) in 2050 for Representative Concentration Pathway 4.5, 6.0, and 8.5 relative to 1850, respectively. Although global mean nitrate values showed a declining trend, future nitrate loading remained high in East Asia and South Asia. Plain Language Summary Nitrate aerosols are effective at scattering solar radiation. Many studies have shown that NOx (NO2 and NO) and NH3 emissions, the main precursors of nitrates, have continued to increase, resulting in a greater proportion of the total anthropogenic aerosols being composed of nitrates. So, it is very likely that nitrate will become an important climate forcing factor at regional and seasonal scales in the future. Although some studies have investigated the DRF values of nitrate, few have used the optical properties of nitrates in atmospheric chemistry-climate online models. This study developed a next-generation atmospheric aerosol/chemistry-climate model, the BCC_AGCM_CUACE2.0. We evaluated the performance of the model and the nitrate direct radiative forcing and effective radiative forcing due to aerosol-radiation interactions for the present day (2010), near future (2030), and middle future (2050) under different Representative Concentration Pathway scenarios, based on the real nitrate optical properties. Our results are useful for understanding the role of nitrate forcing in future climate change. Key Points This study developed a next-generation atmospheric aerosol/chemistry-climate model, which can simulate ERF due to nitrates online The model can reasonably reproduce the distribution and seasonal change of nitrate concentration in Europe, North America, and China Future nitrate ERFs were predicted to be -0.17 to -0.24 W m(-2) and -0.07 to -0.19 W m(-2) in 2030 and 2050, respectively, based on three different scenarios
