The Navy's global atmospheric ensemble forecast system

In March 2008, a new initial perturbation scheme for the global atmospheric ensemble developed at the Naval Research Laboratory (NRL), the ensemble transform, became operational at Fleet Numerical Meteorology and Oceanography Center (FNMOC). This presentation will describe the operational global ensemble system and current research on anticipated improvements. Research topics briefly described will include work on 1) incorporation of model uncertainty in ensemble design, including stochastic parameterizations and parameter variations, as well as incorporation of uncertainty at the lower boundary, 2) work on improving the ensemble transform initial perturbations based on alternative bases, and 3) work in the characterization of initial uncertainty for tropical cyclones. The current operational system and planned upgrades will be described, and examples of operational products, such as wave-height and period products and surface wind and pressure products will be shown.