Aircraft can report in situ observations of the ambient temperature by using aircraft meteorological data relay (AMDAR) or these can be derived using mode‐select enhanced tracking data (Mode‐S EHS). These observations may be assimilated into numerical weather prediction models to improve the initial conditions for forecasts. The assimilation process weights the observation according to the expected uncertainty in its measurement and representation. The goal of this paper is to compare observation uncertainties diagnosed from data assimilation statistics with independent estimates. To quantify these independent estimates, we use metrological comparisons, made with in‐situ research‐grade instruments, as well as previous studies using collocation methods between aircraft (mostly AMDAR reports) and other observing systems such as radiosondes. In this study we diagnose a new estimate of the vertical structure of the uncertainty variances using observation‐minus‐background and observation‐minus‐analysis statistics from a Met Office limited area three‐dimensional variational data assimilation system (3 km horizontal grid‐length, 3‐hourly cycle). This approach for uncertainty estimation is simple to compute but has several limitations. Nevertheless, the resulting diagnosed variances have a vertical structure that is like that provided by the independent estimates of uncertainty. This provides confidence in the uncertainty estimation method, and in the diagnosed uncertainty estimates themselves. In the future our methodology, along with other results, could provide ways to estimate the uncertainty for the assimilation of aircraft‐based temperature observations.

中文翻译：

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将诊断的观测不确定性与独立估计值进行比较：使用基于飞机的观测和对流允许数据同化系统的案例研究

飞机可以使用飞机气象数据中继器（AMDAR）报告环境温度的原位观测值，也可以使用模式选择的增强跟踪数据（Mode-S EHS）导出这些观测值。可以将这些观测值同化为数值天气预报模型，以改善预报的初始条件。同化过程根据观测值的度量和表示中的预期不确定性对观测值进行加权。本文的目的是将根据数据同化统计诊断出的观测不确定性与独立估计进行比较。为了量化这些独立的估计，我们使用了由原位研究级仪器进行的计量比较，以及以前在飞机（主要是AMDAR报告）和其他观测系统（如探空仪）之间使用并置方法进行的研究。在这项研究中，我们使用了Met Office有限区域三维变异数据同化系统（3 km水平网格长度， 3小时周期）。这种不确定性估计的方法易于计算，但有一些局限性。然而，所得的诊断方差具有垂直结构，该垂直结构类似于不确定性的独立估计所提供的垂直结构。这为不确定性估计方法和诊断的不确定性估计本身提供了信心。将来，我们的方法以及其他结果可能会为估算基于飞机的温度观测值的不确定性提供方法。