Articles | Volume 26, issue 11
https://doi.org/10.5194/acp-26-8159-2026
© 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-26-8159-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Observation of the lunar tide in the middle atmosphere by the Aura Microwave Limb Sounder
Klemens Hocke
CORRESPONDING AUTHOR
Institute of Applied Physics, University of Bern, 3012 Bern, Switzerland
Oeschger Centre for Climate Change Research, University of Bern, 3012 Bern, Switzerland
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Short summary
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The observations of the Aura Microwave Limb Sounder (Aura/MLS) indicate the existence of a polar mesospheric precursor of major sudden stratospheric warmings (SSWs). The geopotential height data of Aura/MLS from 2004 to 2021 show that a burst of a 4 day-oscillation (zonally symmetric wave with zonal wavenumber zero) occurs at the stratopause and in the mesosphere at 80° N about 17 days before the central date of the SSW.
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Short summary
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Short summary
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The south-central interior of Andalusia experiences complex precipitation patterns as a result of the semi-arid Mediterranean climate and the influence of Saharan dust. This study monitored the inter-relations between aerosols, clouds, meteorological variables, and precipitation systems using ground-based remote sensing and in situ instruments.
Eric Sauvageat, Klemens Hocke, Eliane Maillard Barras, Shengyi Hou, Quentin Errera, Alexander Haefele, and Axel Murk
Atmos. Chem. Phys., 23, 7321–7345, https://doi.org/10.5194/acp-23-7321-2023, https://doi.org/10.5194/acp-23-7321-2023, 2023
Short summary
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In Switzerland, two microwave radiometers can measure continuous ozone profiles in the middle atmosphere. From these instruments, we can study the diurnal variation of ozone, which is difficult to observe otherwise. It is valuable to validate the model simulations of diurnal variations in this region. We present results obtained during the last decade and compare them against various models. For the first time, we also show that the winter diurnal variations have some short-term fluctuations.
Eric Sauvageat, Eliane Maillard Barras, Klemens Hocke, Alexander Haefele, and Axel Murk
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Short summary
Short summary
We present new harmonized ozone time series from two ground-based microwave radiometers in Switzerland. The new series consist of hourly ozone profiles in the middle atmosphere (~ 20–70 km) from 2009 until 2021. Cross-validation of the new data series shows the benefit of the harmonization process compared to the previous versions. Comparisons with collocated satellite observations is used to further validate these time series for long-term ozone monitoring over central Europe.
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Short summary
The Aura/MLS (Aura satellite/Microwave Limb Sounder) observations of geopotential height and temperature show lunar semimonthly variations which inform about the amplitude profiles and the vertical phase progression of the lunar tide in the middle atmosphere. The observed lunar tide are compared to a simulation of the lunar tide by Geller.
The Aura/MLS (Aura satellite/Microwave Limb Sounder) observations of geopotential height and...
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