C-SRNWP Programme

Annual Report 2001

Prominent during the year under review have been the scientific discussions and the exchange of information between our five Consortia (ALADIN, COSMO, HIRLAM, LACE and UKMO) mainly in our Workshops and to a lesser extend also in the Consortia meetings.
The following SRNWP Workshops took place:
23-24 April in De Bilt: First Workshop on Meso-scale Verification
The first workshop of the year was simultaneously the First Workshop of the Lead Centre for Meso-scale Verification whose creation had been decided at the SRNWP Annual Meeting 2000.
The participation at this first meeting with 23 participants was modest which was unexpected as everybody agrees that we do not know how the very high resolution meso-scale models should be verified in general and more specifically how precipitations and cloudiness should be verified. Important recommendations concerning our future work have been made, the most important one concerning a free exchange between EUMETNET Members of all the SYNOPs messages (not only the 3-hourly ones).
2-3 July in Bratislava: Third Mini-workshop on Numerical Techniques
Most of the problems discussed were related to the non-hydrostatic two time level dynamics. The main points were the coupling of the physics to the dynamics when using a semi-lagrangian technique and the revival of interest in the semi-implicit technique (the choice of the prognostic variables) and in the Davies-Kallberg relaxation scheme (the dipole and aliasing problem).
It has been much regretted that the ECMWF, for the first time in this meeting series, has not sent a representative.
24-26 September in Bad-Orb (Germany): Fourth Workshop on Nonhydrostatic Modelling
Unfortunately, in the aftermath of the 11 September tragic events, it has not been possible for our US colleagues to join the meeting. But the participation retains - with the exception of the USA - its worldwide character, which is a very welcome feature of these workshops.
The main conclusion of the workshop is maybe that the split-explicit method seems today to be the most efficient method for time discretization. The trend to the two time level schemes (2TL) has been confirmed, also for the slit-up methods.
22-24 October in Madrid: Workshop on soil processes, turbulence and mountain effects
It was formally an HIRLAM Workshop which has been extended to a SRNWP Workshop.
Concerning the mountain effects, the main point is the confirmation that our traditional NWP models with terrain following vertical coordinates and same grid for everything (orography, dynamics and physics) have several problems with the orography when the horizontal resolution becomes smaller than 10 km. The remedy is everywhere the same: the orography has to be smoothed. Important was also the conclusion that meso-scale models must also parametrize the mountain gravity wave drag because of its action in the lowest part of the troposphere and at the surface.
Concerning the soil processes, the trend is to leave the ad-hoc models as the force-restore model for explicit multi-layer soil models with the same configuration (number and depth of the layers) for the hydrological and the thermal parts.

Next to these SRNWP Workshops, each Consortia has organised at least two scientific meetings. The Programme Manager participated, next to the HIRLAM Workshop mentioned above, to an ALADIN Workshop (Toulouse, June the 7th) and to the Annual COSMO Meeting (Athens, 5th of October). He could convince himself that the development works made in the different Consortia in 2001 stayed at the same high level as during the previous year. And again he can confirm that all the Consortia are at the same high level of scientific development although the directions or the emphases or the directions taken by the Consortia are not the same. For example HIRLAM devotes a lot of efforts in the variational methods for data analysis when COSMO emphasizes the very high resolution non-hydrostatic modelling.

Another 2001 mile stone concerns the document "NWP Software Exchange between the NWS participating in the EUMETNET C-SRNWP Programme". At its 12th Meeting (6th of April 2001), the EUMETNET Council has accepted our proposal. Now, we have inside EUMETNET a solid basis and a clear procedure when a Member wishes to acquire NWP software from another Member.

The Programme Manager made in 2001 in other organisations than EUMETNET two interventions on matters which will probably have a significant impact on NWP:
The initial TOUGH proposal for a EU Project complementing the activity of the COST Action 716 (Exploitation of Ground Based GPS for Climate and NWP Applications) also foresaw activities on operational issues when at the same time Working Group 4 "Planning for the operational phase" of the Action was working on the subject. The Programme Manager took the initiative to inform the NWS participating in the Action that the operational issues, which are essential for a future operational use of the GPS data, should remain in the responsibility of the COST Action and should later, in the view of the Programme Manager, be coordinated by EUMETNET in the frame of the EUCOS Programme. The initial EU project proposal has eventually been revised and limited its objectives to scientific ones, mainly to the difficult problem of the assimilation of the GPS data by variational techniques.
The "ATOVS Retransmission Service" that EUMETSAT will organise covers Southern Europe much less extensively than Northern Europe. The Programme Manager thought that this was not without a flaw coming from an intergovernmental european institution. Now, the problem is solved: EUMETSAT will implement the scheme as initially defined and in a second step, a southward extention of the coverage will be submitted to the EUMETSAT Council, probably already in 2002.

The SRNWP Annual Meeting 2001, combined as usual with the EWGLAM Meeting, has been organised by the polish Institute for Meteorology and Water Management and took place in Cracow on the 11th and 12th of October. It was a rich meeting with among others a presentation of the BALTEX Project made by Prof. Hantel of the University of Vienna who studies the convection in this Project. As we did it already for the Annual Meeting 2000, we also had a presentation of a EUMETNET Programme: the E-AMDAR Programme has been presented by its Technical Coordinator, Steward Taylor from the UKMO.

The Coordinator of the SRNWP Programme considers it as very important to know how Europe compares with other major countries of the world as the USA, Canada, Japan and Australia in the field of the NWP. To get the best possible picture, he participated to two major Conferences, one in Japan and one in the USA. Although in both Conferences there were ideas that he had not met in Europe, he received confirmation that Europe is by no means neither in model design nor in data assimilation trailing behind. On the contrary. In fields like numerics or 4D-Var, Europe is leading.

Jean Quiby
C-SRNWP Programme Manager