The LS3MIP paper does not contain a detailed description of the seasonal predictability experiments, labeled as LFMIP-Pobs. Draft experimental designs were proposed by Constantin Ardilouze (see attachment) and Bart van den Hurk (see attachment).

The experiment replicates the findings of the GLACE2 predictability study by extending the nr of participating models, period of forecasts, and nr of start dates. As such, the reference simulation is not a transient simulation over the historical record (as is the case for the LFMIP experiments using prescribed land surface conditions), but a set of reforecasts from a seasonal forecast set-up.

For LFMIP-Pobs it is decided to use either the current Copernicus reforecast model data set as a reference forecast, or a new reforecast data set based on the LFMIP model configuration. CMCC, ECMWF and MeteoFrance do participate in this Copernicus program. The model configuration used in these seasonal forecasting programs deviates from the set-up used in the other LFMIP projects.

Experimental set-up

The LFMIP-Pobs experiments duplicate the seasonal reforecasts with the following specifications:

Data request and Diagnostics

The data request is formed by an overlap between the general LS3MIP data request and the output produced in the Copernicus program. Diagnostics address both (perfect model) potential predictability and real (observation/reanalysis based) predictability.

Participating models

The following modelling groups will contribute to this experiment:

Further contributions are seeked from ECMWF (Andrea Alessandri) and modelling groups participating in the Copernicus seasonal forecasting service (notably UKMO and DWD). spacer