Welcome to the homepage of SOLARIS-HEPPA

Solar forcing contributes to the natural variability of the climate system by changes in the solar radiance and solar wind throughout the solar cycle. While direct changes to surface climate have been small in the last decades, other compartments of the Earth system are affected more strongly, providing possible, still not well understood feedback mechanisms enhancing or reducing the solar signal regionally.  

SOLARIS-HEPPA is an international working group within the WCRP/APARC project. The aims of SOLARIS-HEPPA are

• Quantification of the solar signal in different compartments of the Earth system
• Better theoretical understanding of underlying processes coupling the variable solar signal through the different compartments of the Earth system
• Evaluation of the representation of solar forcing in chemistry-climate models
• Provide forcing data for chemistry-climate model experiments, e.g. CMIP
• Assess potential contributions of solar decadal variability on climate variability and near-term (sub-)seasonal and decadal predictions
• Explore limitations and alternative statistical methods to improve accuracy and reliability of (solar signal) attribution

These are addressed in working groups, model-measurement intercomparison experiments as well as in regular meetings of the working group.