In this study, the ionization rate in the atmosphere induced by solar and galactic cosmic rays is calculated for the region of Athens (Greece) during the time period from 1996 to 2019 covering the last two solar cycles 23 and 24. In order to compute the cosmic ray induced ionization, the corresponding model of the University of Oulu was used along with its new version which is extended to the upper atmosphere. This model has been applied to the entire atmosphere, i.e., from the atmospheric depth of 0.00 g/cm² corresponding to the upper limit of the atmosphere (∼40 km), to that one of 1025 g/cm² corresponding to the Earth’s surface. Furthermore, an application has been made as a function of rigidity and geomagnetic latitude, from 0.1 GV (∼90^∘ polar regions) to 14.9 GV (∼0^∘ equatorial regions). Specifically, we focus at the region of Athens that is a middle latitude one, located at 38^∘N geographic latitude, and cosmic ray intensity is recorded by the sea level (260 m) neutron monitor station of the National and Kapodistrian University of Athens. Cosmic ray particles with a vertical cut-off rigidity of 8.5 GV are measured in real time and magnetospheric effects of the cosmic ray intensity with the maximum amplitude in the north hemisphere, are often observed. A comparison of the calculated cosmic ray induced ionization in this region with the ionization of polar and equatorial regions during the different phases of the solar cycles 23 and 24, is performed. A seasonal variation of this ionization during all the examined period is for first time observed. Obtained results are discussed in terms of Space Weather applications.

在这项研究中，计算了 1996 年至 2019 年期间雅典（希腊）地区由太阳和银河宇宙射线引起的大气电离率，涵盖了最后两个太阳周期 23 和 24。为了计算在宇宙射线诱导电离方面，奥卢大学的相应模型与其扩展到高层大气的新版本一起使用。该模型已应用于整个大气层，即从对应于大气上限（~40 公里）的 0.00 g/cm ²的大气深度，到对应于地球表面的 1025 g/cm ^{2 的}深度. 此外，应用已作为刚度和地磁纬度的函数，从 0.1 GV (∼90 ^∘极地地区），以14.9 GV（约0 ^∘赤道地区）。具体来说，我们关注雅典的中纬度地区，位于 38 ^∘N 地理纬度和宇宙射线强度由雅典国立和卡波迪斯特大学的海平面（260 m）中子监测站记录。实时测量垂直截止刚度为 8.5 GV 的宇宙射线粒子，并经常观察到北半球振幅最大的宇宙射线强度的磁层效应。在太阳周期 23 和 24 的不同阶段期间，计算出的该区域中的宇宙射线诱导电离与极地和赤道区域的电离进行了比较。在所有检查期间，这种电离的季节性变化是第一次观察到。在空间天气应用方面讨论了获得的结果。