In this study, we compare the diurnal variation in stratospheric ozone of the MACC (Monitoring Atmospheric Composition and Climate) reanalysis, ECMWF Reanalysis Interim (ERA-Interim), and the free-running WACCM (Whole Atmosphere Community Climate Model). The diurnal variation of stratospheric ozone results from photochemical and dynamical processes depending on altitude, latitude, and season. MACC reanalysis and WACCM use similar chemistry modules and calculate a similar diurnal cycle in ozone when it is caused by a photochemical variation. The results of the two model systems are confirmed by observations of the Superconducting Submillimeter-Wave Limb-Emission Sounder (SMILES) experiment and three selected sites of the Network for Detection of Atmospheric Composition Change (NDACC) at Mauna Loa, Hawaii (tropics), Bern, Switzerland (midlatitudes), and Ny-Ålesund, Svalbard (high latitudes). On the other hand, the ozone product of ERA-Interim shows considerably less diurnal variation due to photochemical variations. The global maxima of diurnal variation occur at high latitudes in summer, e.g., near the Arctic NDACC site at Ny-Ålesund, Svalbard. The local OZORAM radiometer observes this effect in good agreement with MACC reanalysis and WACCM. The sensed diurnal variation at Ny-Ålesund is up to 8% (0.4 ppmv) due to photochemical variations in summer and negligible during the dynamically dominated winter. However, when dynamics play a major role for the diurnal ozone variation as in the lower stratosphere (100–20 hPa), the reanalysis models ERA-Interim and MACC which assimilate data from radiosondes and satellites outperform the free-running WACCM. Such a domain is the Antarctic polar winter where a surprising novel feature of diurnal variation is indicated by MACC reanalysis and ERA-Interim at the edge of the polar vortex. This effect accounts for up to 8% (0.4 ppmv) in both model systems. In summary, MACC reanalysis provides a global description of the diurnal variation of stratospheric ozone caused by dynamics and photochemical variations. This is of high interest for ozone trend analysis and other research which is based on merged satellite data or measurements at different local time.

中文翻译：

---

MACC再分析，ERA临时，WACCM和地球观测数据得出的平流层臭氧的日变化：特征和比较

在这项研究中，我们比较了MACC（监测大气成分和气候）再分析，ECMWF再分析中期（ERA-中期）和自由运行的WACCM（整个大气群落气候模型）平流层臭氧的日变化。平流层臭氧的日变化是由光化学和动力学过程引起的，取决于海拔，纬度和季节。MACC再分析和WACCM使用类似的化学模块，并在臭氧是由光化学变化引起的情况下计算出类似的臭氧昼夜循环。观察超导亚毫米波肢体发射探测器（SMILES）以及夏威夷毛纳罗阿（热带）大气成分变化检测网络（NDACC）的三个选定地点，证实了这两个模型系统的结果，瑞士伯尔尼（中纬度），和斯瓦尔巴特群岛Ny-Ålesund（高纬度）。另一方面，由于光化学变化，ERA-Interim的臭氧产品昼夜变化明显较小。日变化的全球最大值发生在夏季的高纬度地区，例如，在斯瓦尔巴特群岛Ny-Ålesund的北极NDACC站点附近。本地OZORAM辐射计与MACC重新分析和WACCM观察到的效果很好。由于夏季的光化学变化，在Ny-Ålesund感测到的日变化高达8％（0.4 ppmv），而在动态控制的冬季则可以忽略不计。但是，当动力学对平流层下部（100–20 hPa）的昼夜臭氧变化起主要作用时，重新分析模型ERA-Interim和MACC可以同化探空仪和卫星的数据，其性能优于自由运行的WACCM。这样的领域是南极极地冬季，极地涡旋边缘的MACC重新分析和ERA-Interim指出了日变化的令人惊讶的新颖特征。在两个模型系统中，这种影响最多占8％（0.4 ppmv）。总而言之，MACC重新分析提供了由动力学和光化学变化引起的平流层臭氧日变化的全局描述。这对于臭氧趋势分析和其他研究非常感兴趣，这些研究基于合并的卫星数据或不同本地时间的测量值。MACC重新分析提供了由动力学和光化学变化引起的平流层臭氧日变化的全局描述。这对于臭氧趋势分析和其他研究非常感兴趣，这些研究基于合并的卫星数据或不同本地时间的测量值。MACC重新分析提供了由动力学和光化学变化引起的平流层臭氧日变化的全局描述。这对于臭氧趋势分析和其他研究非常感兴趣，这些研究基于合并的卫星数据或不同本地时间的测量值。