宇宙射线作为来自宇宙空间的高能带电粒子，持续轰击地球大气层，是影响地球大气的自然强迫之一，其通量受太阳活动、行星际磁场和地磁场的共同调制。宇宙射线携带的高能粒子电离大气，并通过离子—分子化学过程改变上对流层—下平流层区域臭氧和水汽的浓度水平和垂直结构，进而可能在长时间尺度上影响地球大气成分和气候演变。围绕宇宙射线影响大气成分的研究进展，从大气电离与电导率特征、氮氧化物与自由基生成机制、臭氧响应特征以及水汽反馈路径 4 个方面进行综述。已有研究表明，宇宙射线可通过诱发大气电离生成NO_x和HO_x等活性物种，对平流层和对流层臭氧产生相反的区域差异效应，并可能通过调节温度垂直结构和云微物理过程间接影响水汽分布。不过，当前对于宇宙射线影响大气成分的定量评估仍存在较大不确定性，相关模式对关键过程的刻画也有待完善。基于此，建议未来应重点加强“宇宙射线—臭氧/水汽—气候”多过程耦合机制的定量研究，并发展更精细的离子化学动力学方案和高分辨率气候化学模拟，以加深对宇宙射线这一自然强迫因子在大气成分变化中作用的系统认识。

Abstract： As high-energy charged particles from space, cosmic rays continue to bombard Earth's atmosphere, which is one of the natural forcings affecting the atmosphere. Their flux is modulated by solar activity, the interplanetary magnetic field, and the geomagnetic field. High-energy particles carried by cosmic rays ionize the atmosphere and alter the horizontal and vertical structure of ozone and water vapor concentrations in the Upper Troposphere-Lower Stratosphere (UTLS) region through ion-molecular chemical processes, which may affect atmospheric composition and climate evolution on long time scales. In this paper, the research progress on the influence of cosmic rays on atmospheric composition is reviewed from four aspects: atmospheric ionization and conductivity characteristics, nitrogen oxide and free radical formation mechanisms, ozone response characteristics, and water vapor feedback pathways. Previous studies have shown that cosmic rays can generate active species such as NOx and HOx by inducing atmospheric ionization, produce opposite regional differences in stratospheric and tropospheric ozone, and may indirectly affect water vapor distribution by adjusting the vertical temperature structure and cloud microphysical processes. However, there remains significant uncertainty in the quantitative assessment of the impact of cosmic rays on atmospheric composition, and the characterization of key processes in relevant models needs improvement. Based on this, future research directions are outlined. Quantitative research on the multi-process coupling mechanism of 'cosmic ray-ozone/ water vapor-climate' should be strengthened, and more detailed ion chemical kinetics schemes and highre solution climate-chemical simulations should be developed to deepen the systematic understanding of the role of cosmic rays as a natural forcing factor in changes in atmospheric composition.