MAP D-PHASE
Marco Arpagaus and Mathias W. Rotach, MeteoSwiss, Zurich, Switzerland
The last phase of MAP after the planning, the field, and the analysis phase, respectively, is called D-PHASE, which stands for Demonstration of Probabilistic Hydrological and Atmospheric Simulation of flood Events in the Alps. From the many achievements of MAP (Volkert 2005), flood forecasting and the associated issues of orographic precipitation, high-resolution numerical weather prediction, and hydrological processes have been chosen as the topic for the forecast demonstration project. This contribution provides a short overview on the various activities and plans.
An end-to-end flood forecasting system
The MAP forecast demonstration project aims at establishing a complete forecast chain for heavy precipitation events. It will contain the following elements (Fig. 1):
- Probabilistic forecast of rain intensity and spatio-temporal distribution for lead times between 2 and 5 days. The result will be a pre-alert (including amount and probability) for a certain region. This pre-alert will be sent out to all the participants including atmospheric and hydrological modellers and end users.
- In the days following a pre-alert, the warnings may be re-iterated, corrected (in space, time, or amplitude), or deleted. They will still be based on the ensemble modelling approach.
- If a pre-alert is maintained, short-range (up to 36 hours lead time) high-resolution deterministic forecasts are performed using all the atmospheric models covering the likely impact area. Possibly (if the resources will be available) a poor man's ensemble will be constructed from these. This step is supported by time-adaptive extra soundings performed by or in collaboration with the EUCOS programme of EUMETNET. Also, analysis fields from the VERA analysis will be provided and may be assimilated in the models.
- The output of the high-resolution deterministic atmospheric models is used to drive hydrological models if the area is an impact area (i.e., if one or more end users warrant to have established a hydrological modelling system for the area). Output goes to the concerned end user(s) and is tailored towards their specific needs. Possibilities of performing hydrological ensemble predictions (based on either different atmospheric model outputs or parameter perturbation) will have to be explored.
- Nowcasting of heavy precipitation if suitable observations (e.g. radar network) are available for the area and the specific end user needs timely information.
Table 1 provides a (tentative) list of the participating atmospheric and hydrologic models and the corresponding institutions.
Demonstration period
The demonstration period has been fixed to last from June to November 2007 and covers the classical `MAP season' (fall) as well as the summer season before. The main reason for extending the demonstration phase outside the MAP season is collaboration with a related project: COPS (Convective and Orographically-induced Precipitation Study), an international research project in the framework of `Quantitative Precipitation Forecast' covering areas in southern Germany and eastern France.
As a WWRP Forecast Demonstration Project MAP D-PHASE is closely related to activities within THORPEX. Also the COST 731 action (`Uncertainty propagation within advanced meteo-hydrological forecast systems') is similar in scope and will see D-PHASE as a test bed for investigating concepts in high-resolution ensemble prediction systems and uncertainty feedbacks in various stages of hydro-meteorological modelling.
Organisation
So far D-PHASE is organised as a working group within MAP. The WG meetings have been open and with a wide (and varying) group of participants. At present the time seems to be due to reform the organisational structure by introducing a standing committee in order to guarantee a consistent and lasting work.
In addition, four 'subordinate' working groups have been formed. WG-EU (`End User'; chair: Roberto Ranzi, ranzi@bsing.ing.unibs.it) brings together the different levels of (end) users, which may be `actors' (such as forecasters, using D-PHASE products and producing forecasts for subsequent users) or `users' (such as civil protection agencies), or both. A first Italian end user workshop has been organized in Brescia in November 2004 and attracted some 25 participants. The next step will be to distribute a questionnaire to all potential users to get a better view of the interests and possible commitments of the very heterogeneous end user community, and to organize further end user workshops. WG-VER (`Verification'; chair: Manfred Dorninger, manfred.dorninger@univie.ac.at) has started to work out the basic strategy concerning evaluation protocols for the demonstration phase. The third working group, WG-DI (`Data Interface'; chair: Christian Keil, christian.keil@dlr.de) is exploring the possibilities and defining the needs with respect to data streams and storage. Finally, WG-DP (`Data Policy'; chair: Mathias Rotach, mathias.rotach@meteoswiss.ch) takes care of all the legal matters related to the exchange of data.
To support the chairman of the MAP D-PHASE working group (Mathias Rotach) in coordinating all these efforts, MeteoSwiss has opened the position of a project coordinator. The position has been filled as of July 1st, and Marco Arpagaus (marco.arpagaus@meteoswiss.ch) is happy to assist you in any matter related to MAP D-PHASE.
MAP D-PHASE gets going
After three very successful phases of the Mesoscale Alpine Programme, reflected by an extraordinary (last) MAP meeting in Zadar (Croatia) in early May this year and the edition of the present last MAP Newsletter, MAP has definitively commenced its fourth and final phase. With many activities already going on, and even more still to come, we are looking forward to an exiting and interesting period for the forecasting of heavy precipitation events in the Alps. MAP D-PHASE is on the move!
