TY  - JOUR
A1  - Engel, Andreas
A1  - Möbius, Tanja
A1  - Haase, Hans-Peter
A1  - Bönisch, Harald
A1  - Wetter, Thomas
A1  - Schmidt, Ulrich
A1  - Levin, Ingeborg
A1  - Reddmann, Thomas
A1  - Oelhaf, Hermann
A1  - Wetzel, Gerald
A1  - Grunow, Katja
A1  - Huret, Nathalie
A1  - Pirre, Michel
T1  - Observation of mesospheric air inside the arctic stratospheric polar vortex in early 2003
T2  - Atmospheric chemistry and physics, 6.2006, S. 267-282
N2  - During several balloon flights inside the Arctic polar vortex in early 2003, unusual trace gas distributions were observed, which indicate a strong influence of mesospheric air in the stratosphere. The tuneable diode laser (TDL) instrument SPIRALE (Spectroscopie InFrarouge par Absorption de Lasers Embarqués) measured unusually high CO values (up to 600 ppb) on 27 January at about 30 km altitude. The cryosampler BONBON sampled air masses with very high molecular Hydrogen, extremely low SF6 and enhanced CO values on 6 March at about 25 km altitude. Finally, the MIPAS (Michelson Interferometer for Passive Atmospheric Sounding) Fourier Transform Infra-Red (FTIR) spectrometer showed NOy values which are significantly higher than NOy* (the NOy derived from a correlation between N2O and NOy under undisturbed conditions), on 21 and 22 March in a layer centred at 22 km altitude. Thus, the mesospheric air seems to have been present in a layer descending from about 30 km in late January to 25 km altitude in early March and about 22 km altitude on 20 March. We present corroborating evidence from a model study using the KASIMA (KArlsruhe Simulation model of the Middle Atmosphere) model that also shows a layer of mesospheric air, which descended into the stratosphere in November and early December 2002, before the minor warming which occurred in late December 2002 lead to a descent of upper stratospheric air, cutting of a layer in which mesospheric air is present. This layer then descended inside the vortex over the course of the winter. The same feature is found in trajectory calculations, based on a large number of trajectories started in the vicinity of the observations on 6 March. Based on the difference between the mean age derived from SF6 (which has an irreversible mesospheric loss) and from CO2 (whose mesospheric loss is much smaller and reversible) we estimate that the fraction of mesospheric air in the layer observed on 6 March, must have been somewhere between 35% and 100%.
Y1  - 2006
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/1680
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30-37344
SN  - 1680-7316
SN  - 1680-7324
N1  - © 2006 Author(s). This work is licensed under a Creative Commons License.
VL  - 6
SP  - 267
EP  - 282
PB  - European Geosciences Union
CY  - Katlenburg-Lindau
ER  -