Journal cover Journal topic
Atmospheric Chemistry and Physics An interactive open-access journal of the European Geosciences Union
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
Research article
11 Jun 2018
Review status
This discussion paper is a preprint. It is a manuscript under review for the journal Atmospheric Chemistry and Physics (ACP).
Ultraviolet Radiation modelling using output from the Chemistry Climate Model Initiative
Kévin Lamy1, Thierry Portafaix1, Béatrice Josse2, Colette Brogniez3, Sophie Godin-Beekmann4, Hassan Bencherif1,5, Laura Revell6,7,8, Hideharu Akiyoshi9, Slimane Bekki4, Michaela I. Hegglin10, Patrick Jöckel11, Oliver Kirner12, Virginie Marecal2, Olaf Morgenstern13, Andrea Stenke6, Guang Zeng13, N. Luke Abraham14,15, Alexander T. Archibald14, Neil Butchart16, Martyn P. Chipperfield17, Glauco Di Genova18, Makoto Deushi19, Sandip S. Dhomse17, Rong-Ming Hu4, Douglas Kinnison20, Martine Michou2, Fiona M. O'Connor16, Luke D. Oman21, Giovanni Pitari18, David A. Plummer22, John A. Pyle14, Eugene Rozanov6,23, David Saint-Martin2, Kengo Sudo24, Taichu Y. Tanaka19, Daniele Visioni18, and Kohei Yoshida19 1LACy, Laboratoire de l’Atmosphère et des Cyclones (UMR 8105 CNRS, Université de La Réunion, Météo-France), Saint-Denis de La Réunion, France
2Centre National de Recherches Météorologiques (CNRM) UMR 3589, Météo-France/CNRS, Toulouse, France
3Laboratoire d’Optique Atmosphérique (LOA), Université Lille 1 Sciences et Technologies, Villeneuve d’Ascq, France
4Laboratoire Atmosphères, Milieux, Observations Spatiales, Service d’Aéronomie (LATMOS), CNRS, Institut Pierre Simon Laplace, Pierre et Marie Curie University, Paris, France
5School of Chemistry and Physics, University of KwaZulu Natal, Durban, South Africa
6Institute for Atmospheric and Climate Science, ETH Zürich (ETHZ), Zürich, Switzerland
7Bodeker Scientific, Christchurch, New Zealand
8School of Physical and Chemical Sciences, University of Canterbury, Christchurch, New Zealand
9National Institute of Environmental Studies (NIES), Tsukuba, Japan
10Department of Meteorology, University of Reading, Reading, UK
11Institut für Physik der Atmosphäre, Deutsches Zentrum für Luft- und Raumfahrt (DLR), Oberpfaffenhofen, Germany
12Steinbuch Centre for Computing, Karlsruhe Institute of Technology, Karlsruhe, Germany
13National Institute of Water and Atmospheric Research (NIWA), Wellington, New Zealand
14Department of Chemistry, University of Cambridge, Cambridge, UK
15National Centre for Atmospheric Science, UK
16Met Office Hadley Centre (MOHC), Exeter, UK
17School of Earth and Environment, University of Leeds, Leeds, UK
18Department of Physical and Chemical Sciences, Universitá dell’Aquila, L’Aquila, Italy
19Meteorological Research Institute (MRI), Tsukuba, Japan
20National Center for Atmospheric Research (NCAR), Boulder, Colorado, USA
21National Aeronautics and Space Administration Goddard Space Flight Center (NASA GSFC), Greenbelt, Maryland, USA
22Environment and Climate Change Canada, Montréal, Canada
23Physikalisch-Meteorologisches Observatorium Davos World Radiation Centre, Davos Dorf, Switzerland
24Graduate School of Environmental Studies, Nagoya University, Nagoya, Japan
Abstract. We have derived values of the Ultraviolet Index (UVI) at solar noon from the Tropospheric Ultraviolet Model (TUV) driven by ozone, temperature and aerosol fields from the first phase of the Chemistry-Climate Model Initiative (CCMI-1). Since clouds remain one of the largest uncertainties in climate projections, we simulated only clear-sky UVI. We compared the UVI climatologies obtained from CCMI and TUV against present-day climatological values of UVI derived from satellite data (the OMI-Aura OMUVBd product) and ground-based measurements (from the NDACC network). Depending on the region, relative differences between the UVI obtained from CCMI and TUV and ground-based measurements ranged between −4 % and 11 %.

We calculated the UVI evolution throughout the 21st century for the four Representative Concentration Pathways (RCPs 2.6, 4.5, 6.0 and 8.5). Compared to 1960s values, we found an average increase in UVI in 2100 (of 2–4 %) in the tropical belt (30° N–30° S). For the mid-latitudes, we observed a 1.8 to 3.4 % increase in the Southern Hemisphere for RCP 2.6, 4.5 and 6.0, and found a 2.3 % decrease in RCP 8.5. Higher UV indices are projected in the Northern Hemisphere except for RCP 8.5. At high latitudes, ozone recovery is well identified and induces a complete return of mean UVI levels to 1960 values for RCP 8.5 in the Southern Hemisphere. In the Northern Hemisphere, UVI levels in 2100 are higher by 0.5 to 5.5 % for RCP 2.6, 4.5 and 6.0 and they are lower by 7.9 % for RCP 8.5.

We analysed the impacts of greenhouse gases (GHGs) and ozone-depleting substances (ODSs) on UVI from 1960 by comparing CCMI sensitivity simulations (1960–2100) with fixed GHGs or ODSs at their respective 1960 levels. As expected with ODS fixed at their 1960 levels, there is no large decrease in ozone levels and consequently no sudden increase in UVI levels. With fixed GHG, we observed a delayed return of ozone to 1960 values, the same signal is observed on UVI, and looking at the UVI difference between 2090s values and 1960s values, we found an 8 % increase in the tropical belt during the summer of each hemisphere.

Finally, we show that, while in the Southern Hemisphere UVI is mainly driven by total ozone column, in the Northern Hemisphere both total ozone column and aerosol optical depth drive UVI levels, with aerosol optical depth having twice as much influence on UVI as total column does.

Citation: Lamy, K., Portafaix, T., Josse, B., Brogniez, C., Godin-Beekmann, S., Bencherif, H., Revell, L., Akiyoshi, H., Bekki, S., Hegglin, M. I., Jöckel, P., Kirner, O., Marecal, V., Morgenstern, O., Stenke, A., Zeng, G., Abraham, N. L., Archibald, A. T., Butchart, N., Chipperfield, M. P., Di Genova, G., Deushi, M., Dhomse, S. S., Hu, R.-M., Kinnison, D., Michou, M., O'Connor, F. M., Oman, L. D., Pitari, G., Plummer, D. A., Pyle, J. A., Rozanov, E., Saint-Martin, D., Sudo, K., Tanaka, T. Y., Visioni, D., and Yoshida, K.: Ultraviolet Radiation modelling using output from the Chemistry Climate Model Initiative, Atmos. Chem. Phys. Discuss.,, in review, 2018.
Kévin Lamy et al.
Kévin Lamy et al.
Kévin Lamy et al.


Total article views: 207 (including HTML, PDF, and XML)

HTML PDF XML Total BibTeX EndNote
158 46 3 207 2 2

Views and downloads (calculated since 11 Jun 2018)

Cumulative views and downloads (calculated since 11 Jun 2018)

Viewed (geographical distribution)

Total article views: 207 (including HTML, PDF, and XML)

Thereof 205 with geography defined and 2 with unknown origin.

Country # Views %
  • 1



Latest update: 18 Jun 2018
Publications Copernicus
Short summary
In this study, we simulate the ultraviolet radiation evolution during the 21st century on Earth's surface using the output from several numerical models which participated in the Chemistry-Climate Model Initiative. We present four possible futures which depend on greenhouse gases emissions. The role of ozone-depleting substances, greenhouse gases and aerosols are investigated. Our results emphasize the important role of aerosols for future ultraviolet radiation in the Northern Hemisphere.
In this study, we simulate the ultraviolet radiation evolution during the 21st century on...