06-08 October 2014, Grainau/Garmisch-Partenkirchen, Germany


The workshop is intended to foster and facilitate the exchange of experience of tuning coupled models among climate modeling centres.

Model tuning, using poorly constrained parameters is a key stage in the development cycle of coupled climate models at many modeling centers. The practice usually serves to match model properties to observables, such as the global mean surface temperature and the radiation balance, the spatial distribution of the top of atmosphere energy balance, or even sometimes the trend of global warming during the twentieth century. Yet, model tuning is not often discussed openly in the scientific literature, limiting the exchange of experience among modelers, and maybe even casting doubt to the value of climate models.

The purpose of the workshop is to be a forum to foster and facilitate the exchange of experience in tuning among the climate modeling centers but also very much to encourage a clear communication to the scientific community and to the public on the practice and implications of climate model tuning.

By arranging this workshop at the brink of Coupled Model Intercomparison Project CMIP6, we hope to aid the development of the next-generation models, and to ultimately promote transparency on the topic.

The bulk of the workshop will be devoted to the exchange between climate modelers in presenting and discussing their goals, strategies and experiences to obtain an overview of the tuning done at the modeling centers. Example questions that could be addressed during the workshop are:

  • What aspects of a models climate can and should be tuned?
  • What is the impact of model tuning on climate variability and sensitivity?
  • Is it possible and even desirable to use automatic methods for model tuning?
  • To which degree does tuning dominate global and/or regional biases in model climate, rather than the physics of model parameterizations?
  • Which observations are sufficiently reliable for model tuning, and are there observations that would be needed?

We welcome participants with insight into the model development, in particular those that are involved in the actual model tuning. Because space is somewhat limited at the venue we may have to limit the number of participants per center, if interest is high. Therefore we encourage contacting us as soon as possible, well in advance of the cancellation deadline (22 August 2014), such that we can prioritize participation.