Miller, A. J., P.-M. Poulain, A. R. Robinson, H. G. Arango, W. G. Leslie
and A. Warn-Varnas, 1995:
Quantitative skill of quasigeostrophic forecasts
of a baroclinically unstable Iceland-Faroe Front.
Journal of Geophysical Research, 100, 10,833-10,849.
Using initialization and validation conditions from hydrographic surveys of the Iceland-Faroe Front in August 1993,
shipboard quasi-geostrophic model forecasts executed in real time are evaluated for quantitative skill in terms of
anomaly correlation coefficient and rms error. The prototype dynamical forecasts are synoptically initialized from
two observed initial states and validated against observations obtained 3-4 days later. The forecasts correlate with the
validating observations, yielding anomaly correlation coefficients of 0.75-0.80, which beat persistence-of-day-zero
forecasts by 0.07-0.30, depending on the region of interest and the initial state. Thus this quasi-geostrophic model is
able to forecast the rapidly evolving currents of this front with quantitative skill. The forecast fields of stream
function are also used to diagnose the physical processes of the frontal current variations. Energetic diagnostics
clearly reveal that the frontal current evolution is controlled by baroclinic instability processes. Baroclinic wave
disturbances at middepth serve to transfer available gravitational energy to kinetic energy, which then is transferred
through the water column, resulting in the observed (and modeled) rapid changes in the frontal current.