Example Data of Polychotomous Observations and Ensembles Forecasts

Polychotomous observations with four categories (obsv) and 9-member ensemble forecasts (fcst) of the Nino-3.4 index for January 1961-2000. The forecast data stem from model runs initialized using data for the preceding August 1960-1999. Definition of the four observation "categories": (1) obsv < 26 C; (2) obsv in [26 C,27 C[; (3) obsv in [27 C,28 C[; (4) obsv >= 28 C.

Format

A data frame with 40 rows and 3 columns:

years

integer, year of observation (1961-2000)

obsv

integer, polychotomous observations (categories 1-4; (1) < 26 C; (2) 26-27 C; (3) 27-28 C; (4) >= 28 C)

fcst

numeric matrix [40 x 9], 9-member ensemble forecasts of Nino-3.4 index (degrees C)

Details

The forecast data are from the coupled ocean-atmosphere model of the Centre National de Recherches Meteorologiques (CNRM) of Meteo France and were generated as part of the "Development of a European Multimodel Ensemble System for Seasonal to Interannual Prediction (DEMETER)" project (Palmer et al. 2004). Note that also the examples presented in the 2AFC paper by Mason and Weigel (2009) are based on these data.

References

Palmer, T.N. and Coauthors, 2004: Development of a European ensemble system for seasonal to inter-annual prediction (DEMETER). Bull. Amer. Meteor. Soc., 85, 853-872.
Mason, S.J. and A.P. Weigel, 2009: A generic forecast verification framework for administrative purposes. Mon. Wea. Rev., 137, 331-349