Articles | Volume 26, issue 21
https://doi.org/10.5194/acp-26-15405-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-26-15405-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
03 Nov 2026
Research article |
| 03 Nov 2026
| 03 Nov 2026
Characterizing variability and vertical structure of water vapor in the extratropical lower stratosphere
National Center for Atmospheric Research, Boulder, CO, USA
William J. Randel
National Center for Atmospheric Research, Boulder, CO, USA
Jun Zhang
National Center for Atmospheric Research, Boulder, CO, USA
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Short summary
Water vapor in the stratosphere plays an important role in Earth’s climate. The moist lower atmosphere and the drier stratosphere meet at the tropopause, creating a complex transition region. Using satellite observations and computer model simulations, this study examines how water vapor varies with height and over time near this boundary. We find that satellite datasets disagree on long-term changes, but consistently show that this transition layer extends about 2.5 kms into the stratosphere.
Water vapor in the stratosphere plays an important role in Earth’s climate. The moist lower...
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