Articles | Volume 25, issue 22
https://doi.org/10.5194/acp-25-15741-2025
https://doi.org/10.5194/acp-25-15741-2025
Research article
 | 
17 Nov 2025
Research article |  | 17 Nov 2025

CO2 variability and seasonal cycle in the UTLS: insights from EMAC model and AirCore observational data

Johannes Degen, Bianca C. Baier, Patrick Jöckel, J. Moritz Menken, Tanja J. Schuck, Colm Sweeney, and Andreas Engel

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Cited articles

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Short summary
We investigate the distribution of CO2 in the upper troposphere and lower stratosphere using both, observations and an atmospheric model. Simulating an artificial tracer, we separate CO2 seasonality from long-term trend and transport variability. We found that patterns in the seasonal signal are attributable to large-scale transport features like the subtropical jet or the Brewer-Dobson circulation. Being a powerful diagnostic tool we recommend to use this tracer for model intercomparisons.
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