Articles | Volume 26, issue 10
https://doi.org/10.5194/acp-26-7435-2026
© Author(s) 2026. This work is distributed under
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the Creative Commons Attribution 4.0 License.
Special issue:
https://doi.org/10.5194/acp-26-7435-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
29 May 2026
Research article |
| 29 May 2026
Effects of model grid spacing for warm conveyor belt (WCB) moisture transport into the upper troposphere and lower stratosphere (UTLS) – Part 1: Lagrangian perspective
Cornelis Schwenk
CORRESPONDING AUTHOR
Institute for Atmospheric Physics, Johannes Gutenberg University Mainz, Mainz, Germany
Annette Miltenberger
Institute for Atmospheric Physics, Johannes Gutenberg University Mainz, Mainz, Germany
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Warm conveyor belts (WCBs) are cloud- and precipitation-producing airstreams in extratropical cyclones that are important for the large-scale flow and cloud radiative forcing. We analyze cloud formation processes during WCB ascent in a two-moment microphysics scheme. Quantification of individual diabatic heating rates shows the importance of condensation, vapor deposition, rain evaporation, melting, and cloud-top radiative cooling for total heating and WCB-related potential vorticity structure.
Stefan Niebler, Annette Miltenberger, Bertil Schmidt, and Peter Spichtinger
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Short summary
We studied how model grid-spacing affects how moisture and ice are carried upward in large weather systems that move warm, moist air into the upper troposphere. By comparing high- and low-resolution simulations, we found that models which are able to represent convectively ascending air produce much drier air at high altitudes. This shows that model resolution strongly influences how water and clouds are transported and how they may affect climate.
We studied how model grid-spacing affects how moisture and ice are carried upward in large...
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