Articles | Volume 26, issue 12
https://doi.org/10.5194/acp-26-8999-2026
© 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-26-8999-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
25 Jun 2026
Research article |
| 25 Jun 2026
| 25 Jun 2026
A global view of the stratospheric background, volcanic and wildfire aerosol in the CALIOP era (2006–2023)
Bengt G. Martinsson
CORRESPONDING AUTHOR
Department of Physics, Lund University, Lund, Sweden
Johan Friberg
Department of Physics, Lund University, Lund, Sweden
Moa K. Sporre
Department of Physics, Lund University, Lund, Sweden
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A method to form SO2 profiles in the stratosphere with high vertical resolution following volcanic eruptions is introduced. The method combines space-based high-resolution vertical aerosol profiles and SO2 measurements the first 2 weeks after an eruption with air mass trajectory analyses. The SO2 is located at higher altitude than in most previous studies. The detailed resolution of the SO2 profile is unprecedented compared to other methods.
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Short summary
The highly variable stratospheric aerosol with great importance for the Earth’s climate was investigated with the satellite-based lidar CALIOP (Cloud-Aerosol LIdar with Orthogonal Polarization) during its entire active period 2006–2023. The background aerosol was identified, showing excellent agreement with solar occultation from the volcanically quiescent period (1998–2000), and indicate strong influence from carbonyl sulfide. 15 volcanic eruptions and 5 wildfires caused variability, from background radiative forcing of -0.14 to -0.4 W/m2.
The highly variable stratospheric aerosol with great importance for the Earth’s climate was...
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