8.1Score definitions

The following definitions should be used
Mean error Image Added
Root mean square (rms) error Image Added
Correlation coefficient between forecast and analysis anomalies
Image Added

rms vector wind error Image Added
Mean absolute error Image Added
rms anomaly Image Added

standard deviation of field Image Added where Image Added

S1 score Image Added
Where:
Image Added =the forecast value of the parameter in question
Image Added =the corresponding verifying value
Image Added =the climatological value of the parameter
Image Added =the number of grid points or observations in the verification area
Image Added =the mean value over the verification area of the forecast
anomalies from climate
Image Added =the mean value over the verification area of the analysed
anomalies from climate
Image Added =the forecast wind vector
Image Added = Image Added
Image Added = Image Added
where the differentiation is approximated by differences computed on the verification grid.
The weights Image Added applied at each grid point or observation location are defined as
Verification against analyses: Image Added , cosine of latitude at grid point i
Verification against observations: Image Added , all observations have equal weight