Abstract. The age of air is an important transport diagnostic that can be derived from trace gas measurements and compared to global chemistry climate model output. We describe a new technique to calculate the age of air, measuring transport times from the Earth’s surface to any location in the atmosphere based on simultaneous in situ measurements of multiple key long-lived trace gases. The primary benefits of this new technique include (1) optimized ages of air consistent with simultaneously measured SF₆ and CO₂, (2) age of air from the upper troposphere through the stratosphere, (3) estimates of the second moment of age spectra that have not been well constrained from measurements and (4) flexibility to be used with measurements across multiple instruments, platforms and decades. We demonstrate the technique on aircraft and balloon measurements from the 1990s, the last period of extensive stratospheric in situ sampling, and several recent missions from the 2020s, and compare the results with previously published and modeled values.

中文翻译：

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原位痕量气体测量的空气年龄：新技术的见解


摘要。空气年龄是一种重要的运输诊断，可以通过痕量气体测量得出，并与全球化学气候模型输出进行比较。我们描述了一种计算空气年龄的新技术，根据多种关键长寿命痕量气体的同时原位测量，测量从地球表面到大气中任何位置的传输时间。这项新技术的主要优点包括 (1) 优化的空气年龄与同时测量的 SF ₆ 和 CO ₂ 一致，(2) 从对流层上层到平流层的空气年龄，（3）年龄谱的二阶矩估计，没有受到测量的良好限制，（4）可灵活地用于跨多种仪器、平台和数十年的测量。我们展示了 20 世纪 90 年代、最后一个时期的广泛平流层原位采样以及 2020 年代最近的几次任务的飞机和气球测量技术，并将结果与​​之前发布的和建模的值进行了比较。