Ensemble forecasting greatly expands the prediction horizon for ocean mesoscale variability

Abstract Mesoscale eddies dominate energetics of the ocean, modify mass, heat and freshwater transport primary production in upper ocean. However, forecast skill horizon for ocean mesoscales current operational models is shorter than 10 days: eddy-resolving models, with horizontal resolution finer km mid-latitudes, represent mesoscale dynamics, but initial conditions are hard to constrain available observations. Here we analyze a suite model simulations at high (1/25°) lower (1/12.5°) compare an ensemble lower-resolution simulations. We show that significantly extends predictability between 20 40 days. find lack predictive data assimilative deterministic due uncertainty location features. Ensemble account this filter-out unconstrained scales. suggest advancements analysis forecasting should complement focus on high-resolution modeling