Its long photochemical lifetime makes H₂O a good tracer for mesospheric dynamics. Temperature observations are also critical to study middle atmospheric dynamics. In this study, we present the reprocessing of 18 years of mesospheric H₂O and temperature measurements from the Sub-Millimetre Radiometer (SMR) aboard the Odin satellite, resulting in a part of the SMR version 3.0 level 2 data set. The previous version of the data set showed poor accordance with measurements from other instruments, which suggested that the retrieved concentrations and temperature were subject to instrumental artefacts. Different hypotheses have been explored, and the idea of an underestimation of the single-sideband leakage turned out to be the most reasonable one. The value of the lowest transmission achievable has therefore been raised to account for greater sideband leakage, and new retrievals have been performed with the new settings. The retrieved profiles extend between 40–100 km altitude and cover the whole globe to reach 85^∘ latitudes. A validation study has been carried out, revealing an overall better accordance with the compared instruments. In particular, relative differences in H₂O mixing ratio are always in the ±20 % range between 40 and 70 km and diverge at higher altitudes, while temperature absolute differences are within ±5 K between 40–80 km and also diverge at higher altitudes.

中文翻译：

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Odin/SMR 水蒸气和温度测量的改进以及获得的数据集的验证

其长的光化学寿命使 H ₂ O 成为中间层动力学的良好示踪剂。温度观测对于研究中层大气动力学也很重要。在这项研究中，我们展示了 18 年的中间层 H ₂来自 Odin 卫星上的亚毫米辐射计 (SMR) 的 O 和温度测量值，产生了 SMR 3.0 版 2 级数据集的一部分。先前版本的数据集与其他仪器的测量结果不一致，这表明检索到的浓度和温度受仪器伪影的影响。已经探索了不同的假设，结果证明低估单边带泄漏的想法是最合理的。因此，提高了可实现的最低传输值以解决更大的边带泄漏，并且使用新设置执行了新检索。检索到的剖面在 40-100 公里高度之间延伸，覆盖整个地球，达到 85 ^∘纬度。已经进行了验证研究，揭示了与比较仪器的整体更好的一致性。特别是，H ₂ O 混合比的相对差异始终在40 到 70 公里之间的± 20 % 范围内并在较高海拔处发散，而温度绝对差异在 40 到 80 公里之间在± 5 K范围内并且也在较高海拔处发散.