MAP Newsletter 1

8. Phase I Modelling Activities

Detlev Majewksi, DWD Zentralamt, Abt. Forschung, Postfach 10 04 65, D-63004 Offenbach a.M.

At the MAP Workshop in Zurich, the working group on Numerical Modelling agreed upon the tasks to be performed during Phase I of MAP. These include

systematic forecast evaluation,
"climate" mode numerical simulations,
case studies, and
mesoscale data assimilation.

For task (1), the four centers which perform operational meso-b-scale forecasts for the Alpine region, namely the Deutscher Wetterdienst, Meteo France, the Regional Met. Service Bologna and the Swiss Meteorological Institute, are asked to provide the following plotted charts of their daily 00 UTC forecasts for the period Sept.-Nov. for the years 1994 through 1997:

24-h precipitation (+6h up to +30 h),
12-h, 24-h forecasts of 10m winds,
12-h, 24-h forecasts of the mean sea level pressure.

These maps should also contain isolines of orographic height to indicate the shape of the Alps. As an example, the charts produced at the Deutscher wetterdienst (DWD) are included as Fig.1. The plotted charts will be collected at each of the four institutions mentioned above and later on be evaluated for precipitation events and foehn related flow structures in the Alps. These cases should finally be sent to Peter Binder at the MeteoSwiss for a detailed comparison between the four centers.

For task (3), the PYREX case (15 October 1990, 00-18 UTC) is the prime candidate for a case study since the COMPARE Project has chosen PYREX as Case II of the intercomparison exercise. Philippe Bougeault (Meteo France) will distribute the data and procedures for this case early in 1995. A participation of MAP people is strongly recommended since it will broaden the range of mesoscale models used for this COM PARE case. Two other case (flash floods in Brig, 23 September 1993, and in Vaison la Romaine, 23 September 1992) are very interesting and the author will try to get analyses and boundary data for them in 1995, so that modelling groups will have the opportunity for experimentation on these cases, too.

For tasks (2) and (4), the discussion about the procedures are still ongoing, and seri ous work in these areas will not start before mid-1995.

MAP Newsletter. October`00