In the frame of Earth observation remote-sensing data analysis, synergistic retrieval (SR) and complete data fusion (CDF) are techniques used to exploit the complementarity of the information carried by different measurements sounding the same air mass and/or ground pixel. While more difficult to implement due to the required simultaneous access to measurements originating from different instruments, the SR method is sometimes preferred over the CDF method as the latter relies on a linear approximation of the retrieved states as functions of the true atmospheric and/or surface state.In this work, we study the performance of the SR and CDF techniques when applied to simulated measurements of the Far-infrared Outgoing Radiation Understanding and Monitoring (FORUM) and the Infrared Atmospheric Sounding Interferometer – New Generation (IASI-NG) missions that will be operational in a few years, from two polar-orbiting satellites. The study is based on synthetic measurements generated for the two missions in clear-sky atmospheres. The target parameters of the inversion are the vertical profiles of temperature, water vapor and ozone mixing ratios, surface temperature, and spectral emissivity.We find that for exact matching of the measurements, the results of the SR and CDF techniques differ by less than $\mathrm{1}/\mathrm{10}$ of their errors estimated through the propagation of measurement noise. For measurements with a realistic mismatch in space and time, the two methods provide more different results. Still in this case, however, the differences between the results are within the error bars due to measurement noise. We conclude that, when applied to FORUM and IASI-NG missions, the two methods are equivalent from an accuracy point of view.

中文翻译：

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应用于模拟 FORUM 和 IASI-NG 测量的协同检索和完整数据融合方法

在地球观测遥感数据分析框架中，协同检索 (SR) 和完全数据融合 (CDF) 是用于利用探测相同气团和/或地面像素的不同测量所携带信息的互补性的技术。虽然由于需要同时访问来自不同仪器的测量值而更难实施，但 SR 方法有时优于 CDF 方法，因为后者依赖于作为真实大气和/或表面函数的检索状态的线性近似状态。在这项工作中，我们研究了 SR 和 CDF 技术在应用于模拟测量远红外出射辐射理解和监测 (FORUM) 和红外大气探测干涉仪 – 新一代 (IASI-NG) 任务时的性能，这些任务将在几个年，来自两颗极轨卫星。该研究基于在晴空大气中为这两项任务生成的综合测量结果。反演的目标参数是温度、水汽和臭氧混合比、地表温度和光谱发射率的垂直剖面。我们发现，对于测量的精确匹配，SR 和 CDF 技术的结果相差小于 该研究基于在晴空大气中为这两项任务生成的综合测量结果。反演的目标参数是温度、水汽和臭氧混合比、地表温度和光谱发射率的垂直剖面。我们发现，对于测量的精确匹配，SR 和 CDF 技术的结果相差小于 该研究基于在晴空大气中为这两项任务生成的综合测量结果。反演的目标参数是温度、水汽和臭氧混合比、地表温度和光谱发射率的垂直剖面。我们发现，对于测量的精确匹配，SR 和 CDF 技术的结果相差小于$\mathrm{1个}/\mathrm{10}$通过测量噪声的传播估计他们的错误。对于空间和时间上实际不匹配的测量，这两种方法提供了更多不同的结果。然而，在这种情况下，由于测量噪声，结果之间的差异仍然在误差范围内。我们得出结论，当应用于 FORUM 和 IASI-NG 任务时，这两种方法从准确性的角度来看是等效的。