We describe the change in operational instrument for the routine measurement of column-averaged dry-air mole fraction of several greenhouse gases (denoted X_gas) at the Lauder Total Carbon Column Observing Network (TCCON) site and the steps taken to demonstrate comparability between the two observation systems following a systematic methodology.Further, we intercompare retrieved X_gas values during an intensive intercomparison period during October and November 2018, when both instruments were performing optimally, and on subsequent, less frequent occasions. The average difference between the two observing systems was found to be well below the expected level of uncertainty for TCCON retrievals for all compared species. In the case of $X_{{\mathrm{CO}}_{\mathrm{2}}}$ the average difference was 0.0264±0.0465 % (0.11±0.19 µmol mol⁻¹).

中文翻译：

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来自新西兰劳德的两个傅立叶变换光谱仪的总碳柱观测网络（TCCON）数据的比对

我们描述了在Lauder总碳柱观测网络（TCCON）站点上常规测量几种温室气体（表示为X_气体）的柱平均干空气摩尔分数的操作工具的变化，以及为证明两者之间可比性而采取的步骤。两个观测系统遵循系统的方法论。此外，我们在2018年10月和2018年11月的密集比对期间对两种_气体的X_气体值进行了相互比较，当时两种仪器均处于最佳状态，并且随后出现的频率较低。发现两个观测系统之间的平均差异远低于所有比较物种的TCCON检索的预期不确定性水平。如果是$X_{{\mathrm{一氧化碳}}_{\mathrm{2个}}}$平均差为0.0264±0.0465  ％（0.11±0.19  μ摩尔摩尔^-1）。