Content - Solar Influence

SOLARIS-HEPPA - Solar Influences on Climate

Activity leaders

Katja Matthes
GEOMAR - Helmholtz Centre for Ocean Research
Kiel, Germany

Bernd Funke
Instituto de Astrofisica de Andalucia, CSIC
Granada, Spain


  • John Austin, GFDL/USA
  • Blanca Ayazaüena, Freie Universität Berlin/Germany
  • William Ball, IAC-ETH/Switzerland
  • Slimane Bekki, Service d' aéronomie Paris/France
  • Stefan Bender, Karlsruhe Institute of Technology/Germany
  • Marco Calisto, IAC-ETH/Switzerland
  • Natalia Calvo, University of Madrid/Spain
  • Gabriel Chiodo, University of Madrid/Spain
  • Thomas von Clarmann, Karlsruhe Institute of Technology/Germany
  • Marc Clilverd, British Antarctic Survey/UK
  • Alessandro Damiani, Japan Agency for Marine-Earth Science and Technology/Japan
  • Tatiana Egorova, PMOD/WRC, Davos/Switzerland
  • Victor Fomichev, University of Toronto/Canada
  • Bernd Funke, IAA-CSIC/Spain
  • Rolando Garcia, NCAR/USA
  • Angela Gardini, IAA-CSIC/Spain
  • Lesley Gray, University of Oxford/UK
  • Joanna Haigh, Imperial College London/UK
  • Toshihiko Hirooka, Kyushu University/Japan
  • Lon Hood, University of Arizona/USA
  • Charles Jackman, NASA-GFSC /USA
  • Philippe Keckhut, Service d' aéronomie Paris/France
  • Kuni Kodera, Nagoya University/Japan
  • Alexei Krivolutsky, Central Aerological Observatory/Russia
  • Anne Kubin, Freie Universität Berlin/Germany
  • Yuhji Kuroda, MRI/Japan
  • Alain Lambert, JPL /USA
  • Ulrike Langematz, Freie Universität Berlin/Germany
  • Frank Lefevre, Service d' aéronomie Paris/France
  • Manuel López-Puertas, IAA-CSIC/Spain
  • Francois Lott, Service d' aéronomie Paris/France
  • Dan Marsh, NCAR/USA
  • Katja Matthes, GEOMAR, CAU Kiel/Germany
  • Amanda Maycock, University of Cambridge/UK
  • Gerald Meehl, NCAR/USA:
  • Stergios Misios, University of Thessaloniki/Greece
  • Sanna-Mari Päivärinta, Finnish Meteorological Institute/Finland
  • Kristell Pérot, Chalmers/Sweden
  • Cora Randall, University of Colorado /USA
  • Thomas Reddmann, Karlsruhe Institute of Technology/Germany
  • Craig Rodger, University of Otago/NZ
  • Eugene Rozanov, PMOD/WRC, Davos/Switzerland
  • Hauke Schmidt, MPI-Met/Germany
  • Kirill Semeniuk, University of York /Canada
  • Annika Seppälä, Finnish Meteorological Institute/Finland
  • Drew Shindell, GISS/USA
  • Miriam Sinnhuber, Karlsruhe Institute of Technology/Germany:
  • Gabriele Stiller, Karlsruhe Institute of Technology/Germany
  • M. Takahashi, Univ. Tokyo/Japan
  • Remí Thieblemont, GEOMAR, CAU Kiel/Germany:
  • Klarie Tourpali, University of Thessaloniki/Greece
  • Pekka Verronen, Finnish Meteorological Institute/Finland
  • Stefan Versick, Karlsruhe Institute of Technology/Germany
  • Kaley Walker, University of Toronto/Canada
  • Shingo Watanabe, Univ. Tokyo/Japan
  • Nadine Wieters, University of Bremen /Germany
  • Jan-Maik Wissing, University of Osnabrück /Germany
  • Yosuke Yamashita, Univ. Tokyo/Japan:

Find up-to-date list online:

Activity description

The importance of solar forcing on climate has now been recognised. However, the atmospheric solar signal and its transfer mechanism(s) still remain uncertain. To address these questions, the international working group SOLARIS (in 2012 renamed to SOLARIS-HEPPA) was created to clarify the effects of solar influence on climate with special focus on the importance of middle atmosphere chemical and dynamical processes and their coupling to the Earth's surface with state-of-the art chemistry-climate models (CCMs) as well as mechanistic models and observations. We foster and initiate detailed studies on the "top-down" solar ultra-violet and the "bottom-up" total solar irradiance mechanisms, as well as on the impact of high-energy particles.

In addition, SOLARIS-HEPPA aims to provide a platform for the coordination and discussion of solar-related studies. This includes recommendations for the solar irradiance and solar proton flux data used to drive middle atmosphere and climate models within e.g. the SPARC CCMI activity and WCRP CMIP6 experiments.

The SOLARIS-HEPPA activity is an extension of the GRIPS solar influence intercomparison (Matthes et al., 2003; Kodera et al., 2003). SOLARIS joined with HEPPA (High Energy Particle Precipitation in the Atmosphere) in 2012, bringing together scientists involved in atmospheric modelling using state-of-the art CCMs and CTMs on one hand, and scientists involved in the analysis and generation of satellite data on the other. SOLARIS-HEPPA collaborates with a number of other programmes and groups, such as the initiatives CCMI, DynVar, the EU COST project: "Towards a sounder assessment of the impact of solar variability on the Earth's climate", as well as ROSMIC working group 1 of SCOSTEP's VarSITI (Variability of the Sun and its Terrestrial Impact) programme. The joint SOLARIS-HEPPA initiative will provide a more complete picture of "Solar Influence on Climate" and will enhance the initiative’s visibility.

Published results

Journal publications:

Gillett, N. P., Shiogama, H., Funke, B., Hegerl, G., Knutti, R., Matthes, K., Santer, B. D., Stone, D., and C. Tebaldi, 2016: Detection and Attribution Model Intercomparison Project (DAMIP). Geosci. Model Dev. Discuss., doi:10.5194/gmd-2016-74

Kodera, K., Thiéblemont, R., Yukimoto, S., and K. Matthes, 2016: How can we understand the solar cycle signal on the Earth's surface? Atmos. Chem. Phys. Discuss., doi:10.5194/acp-2016-138 (subm.)

Matthes, K., Funke, B., Anderson, M. E., Barnard, L., Beer, J., Charbonneau, P., Clilverd, M. A., Dudok de Wit, T., Haberreiter, M., Hendry, A., Jackman, C. H., Kretschmar, M., Kruschke, T., Kunze, M., Langematz, U., Marsh, D. R., Maycock, A., Misios, S., Rodger, C. J., Scaife, A. A., Seppälä, A., Shangguan, M., Sinnhuber, M., Tourpali, K., Usoskin, I., van de Kamp, M., Verronen, P. T., and S. Versick, 2016: Solar Forcing for CMIP6 (v3.1). Geosci. Model Dev. Discuss., doi:10.5194/gmd-2016-91 (subm.)

Hood, L., S. Misios, D. Mitchel, L.J. Gray, K. Tourpali, K. Matthes, H. Schmidt, G. Chiodo, R. Thiéblemont, E. Rozanov, D. Shindell, A. Krivolutsky, 2015: Solar Signals in CMIP-5 Simulations: The Ozone Response. Q. J. Roy. Met. Soc., DOI 10.1002/qj.2553.

Mitchell, D., S. Misios, L.J. Gray, K. Tourpali, K. Matthes, L. Hood, H. Schmidt, G. Chiodo, R. Thiéblemont, E. Rozanov, D. Shindell, A. Krivolutsky, 2015: Solar Signals in CMIP-5 Simulations: The Stratospheric Pathway. Q. J. Roy. Met. Soc, doi:10.1002/qj.2530

Misios, S., D.M. Mitchell, L. Gray, K. Tourpali, K. Matthes. L. Hood, H. Schmidt, G. Chiodo, R. Thielemont, E. Rozanov, and A. Krivolutsky, 2015: Solar Signals in CMIP-5 Simulations: Effects Atmosphere-Ocean Coupling, under review QJRMetSoc.

Thiéblemont, R., K. Matthes, N. Omrani, K. Kodera, and F. Hansen, 2015: Solar forcing synchronizes decadal North Atlantic climate variability. Nat. Comm., doi: 10.1038/ncomms9268.

Ermolli, I., Matthes, K., Dudok de Wit, T., Krivova, N. A., Tourpali, K., Weber, M., Unruh, Y. C., Gray, L., Langematz, U., Pilewskie, P., Rozanov, E., Schmutz, W., Shapiro, A., Solanki, S. K., Thuillier, G., and T. N. Woods, 2013: Recent variability of the solar spectral irradiance and its impact on climate modelling. Atmos. Chem. Phys., 13, 3945-3977. doi: 10.5194/acp-13-3945-2013

Funke, B., A. Baumgaertner, M. Calisto, T. Egorova, C.H. Jackman, J. Kieser, A. Krivolutsky, M. López-Puertas, D.R. Marsh, T. Reddmann, E. Rozanov, S.-M. Salmi, M. Sinnhuber, G.P. Stiller, P.T. Verronen, S. Versick, T. von Clarmann, T.Y. Vyushkova, N. Wieters, and J.M. Wissing, 2011: Composition changes after the "Halloween" solar proton event: the High-Energy Particle Precipitation in the Atmosphere (HEPPA) model versus MIPAS data intercomparison study. Atmos. Chem. Phys., 11(3), 9089-9139

Gray, L.J., J. Beer, M. Geller, J.D. Haigh, M. Lockwood, K. Matthes, U. Cubasch, D. Fleitmann, G. Harrison, L. Hood, J. Luterbacher, G. A. Meehl, D. Shindell, B. van Geel, and W. White, 2010: Solar Influences on Climate. Rev. Geophys., 48, RG4001, doi:10.1029/2009RG000282

Manzini, E., and K. Matthes et al., 2010: Natural Variability of Stratospheric Ozone, Chapter 8 in SPARC CCMVal, SPARC CCMVal Report on the Evaluation of Chemistry-Climate Models, V. Eyring, T. G. Shepherd, D. W. Waugh (Eds.) SPARC Report No. 5, WCRP-X, WMO/TD-No. X.

Austin, J., K. Tourpali, E. Rozanov, H. Akiyoshi, S. Bekki, G. Bodeker, C. Brühl, N. Butchart, M. Chipperfield, M. Deushi, M. Giorgetta, L. Gray, K. Kodera, D. Kinnison, E. Manzini, D. Marsh, K. Matthes, T. Nagashima, T. Shepherd, K. Shibata, R. S. Stolarski, H. Struthers, 2008: Coupled chemistry climate simulations of the solar cycle in temperature and ozone. JGR 113, D11306, doi: 10.1029/2007JD009391

Find more science articles at

SPARC activity updates:

SPARC newsletter No. 44, 2015, p. 14: Report on the 2nd Joint SOLARIS-HEPPA Meeting, 5-9 May 2014, Baden-Baden, Germany, by K. Matthes, B. Funke, and G. Stiller.

SPARC Newsletter No. 40, 2013, p. 33: Report on the 1st Joint SOLARIS-HEPPA Meeting, by  K. Matthes, B. Funke, and C. Randall.

SPARC Newsletter No. 36, 2011, p. 1: Report on 2010 SOLARIS Activities and Future Plans, by K. Matthes and K. Kodera.

SPARC Newsletter No. 36, 2011, p. 28: The High-Energy-Particle Precipitation in the Atmosphere (HEPPA) Model vs. Data Inter-comparison: Lessons Learned and Future Prospects, by B. Funke.

SPARC Newsletter No. 28, 2007, p. 19: Report on the first SOLARIS workshop, 4-6 October 2006, Boulder, Colorado, USA, by K. Matthes et al. 

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