...for details about the validation algorithm: see here

Interpretation of validation results

Best estimate vs. forecast

The forecast is the deterministic part of the TOPAZ simulation, which starts on the bulletin date. Thus, there is one 10 day forecast for each bulletin date. The best estimate is one long time series, built from the one-week ensemble runs which tie together the analysis and the state on the following bulletin date (the bulletin lags the corresponding analysis by one week).

The forecast is initialized with an analysis which is valid one week before the bulletin date. Results from the first simulation week of the forecast, which leads up to the bulletin date, are not validated, and consequently not displayed here.

Uncertainties in the products

Instrument observations are never perfect representations of the true state. The observational product for sea ice type is derived from an adavanced, complex algorithm. Thus, it is likely that the observational uncertainty is significant. A more detailed presentation of the error sources are provided in this presentation, which was given at the general assembly of the European Geophysical Union in 2017.