Vertical distribution of halogenated trace gases in the summer Arctic stratosphere based on two independent air sampling methods

Abstract

Many halogenated trace gases are important greenhouse gases and/or contribute to stratospheric ozone depletion, yet their spatial distribution and temporal evolution in the stratosphere remain poorly constrained. We here present a new high-altitude dataset of a large range of these gases. The results are based on a large balloon flight in the Arctic in summer 2021. Air samples were collected using a passive (AirCore) as well as an active (cryogenic) technique; the former being the largest AirCore flown to date, thus enabling the quantification of an expanded variety of halogenated gases. The evaluation of the results demonstrates good comparability in most cases, but also revealed strengths and weaknesses for both sampler types. In addition, we show examples of the scientific value of this data, including the identification of air masses likely originating from the Asian Monsoon region, and the derivation of the average stratospheric transit times (i.e., the mean ages of air) from multiple tracers.