Kuciauskas, Arunas P. (Naval Reserach Laboratory, Monterey, California)
Brody, L.Robin (same affiliation)
Bankert, Richard L. (same affiliation)
Tag, Paul M. (same affiliation)
Hadjimichael, Michael (same affiliation)
The Mediterranean Sea is surrounded by complex topography which can channel local winds into gale or storm force conditions that can seriously impact Naval operations. Predicting the onset of these wind occurrences required sophisticated forecast products together with experienced weather forecasters, both of which might not be readly available during Naval operations, particularly on smaller ships. NRL is currently developing a software package, MEDEX, which consolidates numerous forecast rules into a user- friendly training tool and forecst guide for shipboard use. These rules were designed and developed under the guidance of an expert with 20 years forecasting experience in Mediterranean meteorology.
MEDEX is a nowcasting tool for predicting the onset, continuation or cessation of gale force events for seven dominant wind types in the Mediterranean: bora (Adriatic Sea), bora (Aegean Sea), etesian, levante, mistral, sirocco and westerly (poniente and vendaval). MEDEX is designed primarily from the expertise and rule base developed by th British Royal Navy (Brody and Nestor, 1980) and operates from the basic meteorological parameters that can be accessed from surface and 500 mb charts. Users are prompted to supply positions and strengths of features such as troughs and ridges, as well as surface pressure differences between designated locations around the Mediterranean. MEDEX makes use of fuzzy logic to more accurately capture the expert's knowledge and to smoothly approximate the likelihood of gale force winds. These fuzzy rules are less sensitive to input inaccuracies and user uncertainties then are traditional rules.
This paper will discuss the general design of MEDEX and present results of MEDEX performance compared to ground truth data over a 2-year period. Initial findings show that MEDEX compares favorably to wind warning forecasts issued by Rota, Spain, the Navy's regional forecast office.
References
Brody,L.R. and M.J.R.Nestor, 1980: Regional Forecasting Aids for the Mediterranean Basin (Handbook for forecasters in the Mediterranean, Part 2). Naval Environmental Prediction Research Facility, Monterey, California, 93943-5502, 178 pp.