1. A. Montani. - COSMO-LEPS for Sochi 2014 Development of a LAM-EPS system for Sochi- 2014 Winter Olympics Andrea Montani C. Marsigli, T. Paccagnella ARPA-SIMC HydroMeteoClimate Regional Service of Emilia-Romagna, Bologna, Italy XIII COSMO meeting Rome (I), 5-8 September 2011

2. A. Montani. - COSMO-LEPS for Sochi 2014 Introduction After Athens (Summer 2004) and Turin (Winter 2006), for the third time in a decade the Olympic Games being hosted by a COSMO-country. Next Olympics and Paralympics Winter Games will take place in Sochi, Russia (7-23 February and 7-16 March 2014). In the past occasions, the involvement of the full consortium was limited in terms of implementation/support of new modelling products. As for Sochi-2014 Winter Olympics, Roshydromet is organizing a blended RDP/FDP (Research and Development Project / Forecast Demonstration Project) under the auspices of WMO: FROST-2014 (Forecasting and Research: the Olympic Sochi Testbed). A new COSMO PP (CORSO) is being set-up to avoid duplication of work and to better coordinate COSMO activities within this RDP/FDP.

3. A. Montani. - COSMO-LEPS for Sochi 2014 Some geography… Sochi (RU) Rome (I)

4. A. Montani. - COSMO-LEPS for Sochi 2014 Tiziana!!! Detlev!!! Andrea!!!

5. A. Montani. - COSMO-LEPS for Sochi 2014 COSMO vs FROST-2014 COSMO should perform a number of activities related to FROST-2014: a)deterministic forecasting (FDP/RDP initiatives), b)probabilistic forecasting: b1) FDP initiatives (“ clone” of COSMO-LEPS over the Sochi area), b2) RDP initiatives (development of a convective-scale COSMO LAM-EPS for the Sochi area), c)post-processing and product generation (FDP/RDP initiatives), d)verification (FDP/RDP initiatives).

6. A. Montani. - COSMO-LEPS for Sochi 2014 FDP (Forecast Demonstration Project) initiatives SOCHMEL: SOCHi-targeted Mesoscale EnsembLe system (“relocation” of COSMO-LEPS) Horizontal resolution: 7 km (  SOCHMEL7). Vertical resolution: 40 model levels. Forecast range: 72 hours. Starting time: 00UTC, 12UTC. Ensemble size: 10 members. Initial and boundary conditions: interpolated from selected ECMWF EPS members. Soil field initialisation: either using DWD Soil Moisture Analysis fields (like in COSMO-LEPS) or from hindcast COSMO run.

7. A. Montani. - COSMO-LEPS for Sochi 2014 SOCHMEL suite @ ECMWF: present prototype d+3dd+2d+1 ECMWF EPS clustering interval Cluster Analysis and RM identification 4 variables Z U V Q 3 levels 500 700 850 hPa 2 time steps Cluster Analysis and RM identification Black-Sea area Complete Linkage 10 Representative Members driving the 10 COSMO-model integrations (weighted according to the cluster populations) employing either Tiedtke or Kain-Fristch convection scheme (randomly choosen) + perturbations in turbulence scheme and in physical parameterisations SOCHMEL clustering area Δx ~ 7 km; 40 ML; fc+72h; initial time: 00UTC, 12UTC; computer time (~ 2 million BUs for 2012) provided by an ECMWF Special Project; suite managed by ARPA-SIMC; contributions from ECMWF member states could be needed in the future. SOCHMEL Integration Domain this prototype is ready!

8. A. Montani. - COSMO-LEPS for Sochi 2014 Types of perturbations As for types and values, the results from CSPERT experimentation are followed (* denotes default values for COSMO v4.12 ): convection_scheme (either Tiedtke* of Kain-Fritsch), tur_len (either 150, or 500*, or 1000), pat_len (either 500*, or 2000), crsmin (either 50, or 150*, or 200), rat_sea (either 1, or 20*, or 40), rlam_heat (either 0.1, or 1*, or 5), mu_rain (either 0.5* or 0), cloud_num (either 5x10^8* or 5x10^7).

9. convection scheme: T=Tiedtke KF=Kain-Fritsch; tur_len: maximal turbulent length scale (default 500m); this parameter is used mainly in the calculation of the characteristic length scale for vertical mixing and thus into the calculation of the vertical transport momentum coefficient; pat_len: length scale of thermal surface patterns (default 500m); this parameter is mainly used in the calculation of the large-scale part of the equation addressing the heat flux parameterisation; horizontal length; rlam_heat: scaling factor of the laminar layer depth (default 1); it defines the layer with non- turbulent characteristics (molecular diffusion effects only); rat_sea: ratio of laminar scaling factors for heat over sea (default 20); crsmin: minimal stomata resistance (default 150); Cloud_num: Cloud droplet number concentration; Mu_rain: Exponent of the raindrop size distribution; ( gscp: Switch on/off of the graupel scheme).

10. A. Montani. - COSMO-LEPS for Sochi 2014 Submitted end of April 2011!

11. A. Montani. - COSMO-LEPS for Sochi 2014 RDP (Research and Development Project) initiatives SOCHMEL28: convective-scale ensemble system (possible prototype) Horizontal resolution: 2.8 km. Vertical resolution: 50 model levels. Forecast range: 48 hours. Starting time: 00UTC, 12UTC. Ensemble size: 5 members. Boundary conditions: either from SOCHMEL7 or from deterministic systems. Initial conditions: either from SOCHMEL7 or from deterministic systems. Data assimilation: … Provision of wind-gust forecasts using different diagnostic algorithms.

12. A. Montani. - COSMO-LEPS for Sochi 2014 Important ingredients for a successful ensemble 1.Have a clear division between FDP and RDP activities / commitments. 2.Develop experience with the use of probabilities by local forecasters. 3.Need of feedback on the top-priority products to be generated / visualised. 4.Computer time. 5.Timeliness in product delivery. 6.Observations to assess the quality of the system in the development phase. 7.…

13. A. Montani. - COSMO-LEPS for Sochi 2014 Potential problems and open issues Access to real-time ECMWF data via an independent way from COSMO-LEPS time-critical application. Computer time: Special Project at ECMWF may not be enough, especially if RDP component is implemented. Timeliness of delivery: test data-flow as soon as possible, ensure solidity to the suite. Need to downscale information at local sites over complex topography. Forecasters do not always like probabilities. End-users “hate” probabilities. … Timetable (from FROST-2014) Pre-trial: 2011/12 winter. Trial: 2012/13 winter. Olympics: 2014 winter.

14. A. Montani. - COSMO-LEPS for Sochi 2014 Thank you !

15. A. Montani. - COSMO-LEPS for Sochi 2014 Outline 1)Introduction to Sochi-2014: a)What is it? b)What has to do with COSMO? 2)COSMO ensemble activities within FROST-2014: a)introduction to SOCHMEL (the SOCHi-targeted Mesoscale EnsembLe system); b)methodology; c)phases of development; d)planned activity. 3)Final remarks.

16. A. Montani. - COSMO-LEPS for Sochi 2014 COSMO-LEPS (developed at ARPA-SIMC) What is it? It is a Limited-area Ensemble Prediction System (LEPS), based on COSMO-model and implemented within COSMO (COnsortium for Small-scale Modelling, including Germany, Greece, Italy, Poland, Romania, Russia, Switzerland). Why? It was developed to combine the advantages of global-model ensembles with the high-resolution details gained by the LAMs, so as to identify the possible occurrence of high- impact and localised weather events (heavy rainfall, strong winds, temperature anomalies, snowfall, …)  generation of COSMO-LEPS to improve the forecast of high-impact weather in the short and early-medium range (up to fc+132h)

17. A. Montani. - COSMO-LEPS for Sochi 2014 EPS 00 UTC (51 members) EPS 12 UTC (51 members) Cluster Analysis 5 Representative Members BOLAM COSMO WRF EPS 00 UTC (51 members) EPS 12 UTC (51 members) Cluster Analysis 16 Representative Members COSMO LEPS Multimodel Ensemble 15 members Multianalysis Model Perturbed Ensemble 16 members BUILDING THE ENSEMBLE: SELECTION OF REPRESENTATIVE MEMBERS (3)

18. A. Montani. - COSMO-LEPS for Sochi 2014 Doubts and open issues Deterministic modelling: 1-km COSMO has never been tested in winter in the operational mode; what about support from the model developers? Are there sufficient computer resources at RosHydroMet to run the 1-km model on a reasonable-size domain (but what is the reasonable domain size for Sochi)? Downscaling from 7-km to 1 km can give rise to spin up problems at the early stage of the forecast. Verification: RosHydroMet can, most likely, provide the project partners with additional in-situ observations not normally available on the GTS. Verification: methodology and observations (the same for all models!). Ensemble modelling: Forecasters do not always like probabilities (at any scale!) End-users “hate” probabilities.

19. A. Montani. - COSMO-LEPS for Sochi 2014 Timetable Pre-trial: 2011/12 winter test data flow, products delivery Trial: 2012/13 winter Olympics: 2014 winter.