1. ECODAM 03/02/201 OD Natural Environment On the St Nicholas’ storm: some results and comments J. Ozer, S. Legrand and V. Duliere ECODAM – 03/02/2014

2. ECODAM 03/02/201 OD Natural Environment Structure Evaluation of the risk of flood in Belgium: who’s who The St Nicholas’ storm Operational modelling tool’s at OD Nature Analysis of HW forecast at Ostend Quality assessment of sea surface elevation in the North Sea Lessons and perspectives

3. ECODAM 03/02/201 OD Natural Environment Evaluating the risk of flood in Belgium: Who’s who

4. vv OD Nature v … … … Information flow for calm weather

5. OD Nature if 5,40m < forecast < 5,60m: Heightened vigilance MDK must inform these agencies of a high HW by phone or by SMS

6. OD Nature if 5,60m < forecast < 5,90m: Storm surge alert Telegraaf kantoor informs these agencies of a high HW by phone and by email

7. OD Nature if forecast > 5,90m: Dangerous storm surge alert Telegraaf kantoor informs these agencies of a high HW by phone and by email

8. ECODAM 03/02/201 OD Natural Environment The St Nicholas’ storm

9. ECODAM 03/02/201 OD Natural Environment The St Nicholas’ storm: December 5 th at 00:00 UTC Wind and atmospheric pressure Surge elevation (TW-TO)

10. ECODAM 03/02/201 OD Natural Environment The St Nicholas’ storm: December 5 th at 12:00 UTC Wind and atmospheric pressure Surge elevation (TW-TO) HW

11. ECODAM 03/02/201 OD Natural Environment The St Nicholas’ storm: December 6 th at 00:00 UTC Wind and atmospheric pressure Surge elevation (TW-TO) HW

12. ECODAM 03/02/201 OD Natural Environment CSM NOS BCZ 2D 5’x2.5’ (~6 km) Tide (η, U, V); P a ; W 10 3D 5’x2.5’ (~6 km); 20 layers Tide (η, U, V); P a ; W 10,T a, cloud coverage, rainfall, specific humidity 3D: ~750 m; 10 layers; OB from NOS, surf. as NOS OMNECS ADI Operational modelling tools at OD Nature: OPTOS MDK

13. ECODAM 03/02/201 OD Natural Environment Operational modelling tools: met forcing (Met. Office) OPTOSOPSYS 0.833°x0.556° 6 hours up to t 0 +72; 12 hours after 9 variables; 5 days 1.25° and 6 hours up to t 0 +36 2.50° and 12 hours up to t 0 +96 3 variables

14. ECODAM 03/02/201 OD Natural Environment Analysis of HW forecast at Ostend: Monday evening HW above alarm level (CSM and BCZ) Internal alert to model officers 1953

15. ECODAM 03/02/201 OD Natural Environment Analysis of HW forecast at Ostend: Tuesday 3 models above alarm First contacts with MDK and OMS MDK: 1 st “Gevaarlijk stormtij kust” message by SMS Add Optos_ADI

16. ECODAM 03/02/201 OD Natural Environment ADI GFS of NCEP (US) Grid: 0.25°x0.125°: 3 hourly, 5 days Download (~2 hrs) + pre-processing Analysis of HW forecast at Ostend: Tuesday Grid as for CSM and OMNECS OBC as for OMNECS Multi Model ensemble forecast; 4 runs/day

17. ECODAM 03/02/201 OD Natural Environment Analysis of HW forecast at Ostend: Wednesday 1 st results of ADI; for Wednesday runs, good agreement MDK: 1 st warning; 1 st alarm Release to the public: RMI (warning pictogram); press 21:30 MDK updates its official warning Some hardware problems (ftp; web site): SS informed

18. ECODAM 03/02/201 OD Natural Environment Analysis of HW forecast at Ostend: Thursday Morning runs: HW ↗ SS solves problems from San Diego OD Nature forecast in media 18:45: Please “speed up your forecast” Evening runs: small HW ↘ 19:30: OMS 6.30 +/- 0.20 m Exchange of mails with OMS up to … (quite late)

19. ECODAM 03/02/201 OD Natural Environment Analysis of HW forecast at Oostende: observations 6.33 6.25 6.19

20. ECODAM 03/02/201 OD Natural Environment Analysis of HW forecast at Ostend: Thursday “Whatever happens, we issued a forecast by all scientific and operational standards” (DD [OMS] 05/12 at 21:22).

21. ECODAM 03/02/201 OD Natural Environment Quality assessment of sea surface elevation

22. ECODAM 03/02/201 OD Natural Environment 1.Wick 2.Northshields 3.Sheerness 4.Ostend 5.Hoek van Holland 6.Den Helder 7.Borkum 8.Cuxhaven 9.Husum 10.Esbjerg NOOS exchange of forecast and observations

23. ECODAM 03/02/201 OD Natural Environment

24. ECODAM 03/02/201 OD Natural Environment B-NL coasts NL-DE-DK coastsUK coasts

25. ECODAM 03/02/201 OD Natural Environment Lessons and perspectives An excellent cooperation and data flow between OD Nature – OMS/RMI – MDK Quality of our forecast along UK coastline and in the southern bight of the North Sea  Quality of our forecast in the German Bight Problem with www and FTP servers

26. ECODAM 03/02/201 OD Natural Environment Lessons and perspectives Need to re-invest in storm surge forecasting:  Further calibration of optos models  Access to more meteorological forecast  Up to 4 forecast cycle / day; ensemble forecast Reinforce the link with RMI and MDK  Daniel Gellens is in favor of the creation of a RMI-OD Nature group for marine forecast  Debriefing with David Dehenauw on Wednesday Improve our visibility to the general public  Clarifying of our role in the issue of marine alerts

27. ECODAM 03/02/201 OD Natural Environment St Nicholas’ storm 5 th & 6 th Dec. 2013 W. Bruyns, tweet, 2013/12/05 9:05PM @ Port of Antwerp Dagebuell, Germany, © EPA/CARSTEN REHDER Eroded beaches between Ostend and Bredene, Belgium, © LaLibre