8.1Score definitions
The following definitions should be used
Mean error
Root mean square (rms) error
Correlation coefficient between forecast and analysis anomalies
rms vector wind error
Mean absolute error
rms anomaly
standard deviation of field where
S1 score
Where:
=the forecast value of the parameter in question
=the corresponding verifying value
=the climatological value of the parameter
=the number of grid points or observations in the verification area
=the mean value over the verification area of the forecast
anomalies from climate
=the mean value over the verification area of the analysed
anomalies from climate
=the forecast wind vector
=
=
where the differentiation is approximated by differences computed on the verification grid.
The weights applied at each grid point or observation location are defined as
Verification against analyses: , cosine of latitude at grid point i
Verification against observations: , all observations have equal weight