TY - JOUR A1 - Müller, Stefan A1 - Hoor, Peter A1 - Bozem, Heiko A1 - Gute, Ellen A1 - Vogel, Bärbel A1 - Zahn, Andreas A1 - Bönisch, Harald A1 - Keber, Timo A1 - Krämer, Martina A1 - Rolf, Christian A1 - Riese, Martin A1 - Schlager, Hans A1 - Engel, Andreas T1 - Impact of the Asian monsoon on the extratropical lower stratosphere: trace gas observations during TACTS over Europe 2012 T2 - Atmospheric chemistry and physics N2 - The transport of air masses originating from the Asian monsoon anticyclone into the extratropical upper troposphere and lower stratosphere (Ex-UTLS) above potential temperatures Θ =  380 K was identified during the HALO aircraft mission TACTS in August and September 2012. In situ measurements of CO, O3 and N2O during TACTS flight 2 on 30 August 2012 show the irreversible mixing of aged stratospheric air masses with younger (recently transported from the troposphere) ones within the Ex-UTLS. Backward trajectories calculated with the trajectory module of CLaMS indicate that these tropospherically affected air masses originate from the Asian monsoon anticyclone. These air masses are subsequently transported above potential temperatures Θ =  380 K from the monsoon circulation region into the Ex-UTLS, where they subsequently mix with stratospheric air masses. The overall trace gas distribution measured during TACTS shows that this transport pathway had affected the chemical composition of the Ex-UTLS during boreal summer and autumn 2012. This leads to an intensification of the tropospheric influence on the extratropical lower stratosphere with PV  >  8 pvu within 3 weeks during the TACTS mission. During the same time period a weakening of the tropospheric influence on the lowermost stratosphere (LMS) is determined. The study shows that the transport of air masses originating from the Asian summer monsoon region within the lower stratosphere affects the change in the chemical composition of the Ex-UTLS over Europe and thus contributes to the flushing of the LMS during summer 2012. Y1 - 2016 UR - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/42009 UR - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-420098 UR - http://www.atmos-chem-phys.net/16/10573/2016 SN - 1680-7324 SN - 1680-7316 N1 - © Author(s) 2016. CC Attribution 3.0 License. VL - 16 IS - 16 SP - 10573 EP - 10589 PB - European Geosciences Union CY - Katlenburg-Lindau ER -