1. Unified Model Developments 2002
Clive Wilson
NWP
Met Office

2. Outline Configurations & Users Global and UK Mesoscale Changes
Regional European Model
New supercomputer
Plans

3. Operational Versions & External Users
Global
38 levels, N216= 432x325 (~60km)
UK Mesoscale
38 levels, 0.11 deg (12km)
Stratospheric
42 levels 100-1hpa), N48=96x73 (~300km)
Crisis models (LAMS)
Middle East, Former Yugoslavia,SW Asia
External
CGAM UK, ICM Warsaw, Thai Met Service, New Zealand, DNMI

4. Changes Global UK Mesoscale G26 16 Oct 3dvar upgrade
Increase Observation errors for AMVs
Revise thinning of ATOVS to give preference to microwave-clear over IR-clear
Use of fractional sea-ice in ATOVS processing
G27 7 August 2002 New Dynamics and HadAM4
G28 1 Oct Introduce NOAA17
UK Mesoscale
G27 7 August 2002 New Dynamics

5. *Already operational in Mesoscale Model

6. Expected benefits of New Dynamics
Non-hydrostatic capability – ability to increase resolution in UK area.
Improved stability and accuracy - less noise in forecasts
Improved physics for global model - improved coupling to dynamics.
Unify physics between global and UK area - Better boundary conditions.
Better coupling with 3D-Var which was designed around new grid.

7. New Dynamics levels

8. Bars show the %change in RMSE (NDHadAM4 - OP/OP) for the components, which make up the NWP index. Verification is against observations. Blue signifies Northern Hemisphere, red the Tropics and Green is the Southern Hemisphere. A negative value implies NDHadAM4 is an improvement over OP.

10. Typhoon Phanfone
18 August 2002

12. Screen temperature OP ND mean forecast range forecast range rms
Shadow suite (16/1-4/2), all stations OP ND
mean
forecast range
forecast range
rms

13. 10-metre wind OP ND mean speed rms vector 0 12 24 36
Shadow suite (16/1-4/2), all UK stations OP ND
mean
speed
rms
vector

14. Relative Humidity OP ND mean forecast range rms 0 12 24 36
Shadow suite (16/1-4/2), all stations OP ND
mean
forecast range
rms

15. Visibility
Shadow suite (6/12-4/2), all stations

16. Rainfall (skill) Shadow suite (6/12-28/1)
v Nimrod 6-hourly accumulations

17. Rainfall (bias) Shadow suite (6/12-28/1)
v Nimrod 6-hourly accumulations

18. Strong summer convection

19. ND OP
T+0
French Storm Vt 12Z 27/12/1999
T+72

20. OP ND
T+0
Danish Storm Vt 12Z 03/12/1999
T+24

21. Reduced Noise in New Dynamics

22. New Dynamics Summary Benefits Problems
Reduced NH RMSE in summer and at early FC ranges in winter
Deeper extratropical cyclones
Reduced temperature biases
Improved stratospheric circulation statistics (eddy temperature fluxes)
Reduced noise in ND forecasts.
Improved radiative balance - OLR
Tropical upper level wind RMSE too large (~6-10%)
SH T+24 wind RMSE too large (vs analysis) - corrections ready
Grid point storms at N216.
Tuning of orographic and BL drag and diffusion still required.
Low cloud in UK mesoscale
Poor initial precipitation in UK Mes

23. New Regional European model
Opportunity to reorganise Operational suite
New dynamics model formulation (August 2002)
Better Global performance but double cost
2X number of processors to keep to delivery time
Mesoscale ~same as current
relatively more efficient than global
Remove duplication of Global Preliminary/Main runs

24. Resources Make full use of operational time & processors Processors
global 288, UKmes 108  factor of 2.8
Release duplicate Prelim/main
analysis +2 day forecast (=40min)
60min slot (=20 min gap + “duplicate time”)
~5X UKmes cost

25. Proposed Domain 548 320 New Euro Mes 20km resolution
Current UK mesoscale
320
New Euro Mes 20km resolution

26. Current Operational Schedule
00/12
+1:50
2 Days
Prelim Run P
00/12
Boundary Forcing
+2:40
2 Days
+3:00
Main Run
6 Days G
Ocean, wave, surge
+4:50
2 Days
+7:50
Prelim Run P

27. Proposed Operational Schedule
2 Days
Main Run part 1
00/12
+1:50
00/12
Continued Main Run
Days 2-6
+3:40
+3:00 E
2 Days
Euro Run
Boundary Forcing
2 Days
+2:40
Ocean, wave, surge
+4:50

28. Estimated Global worsening
250hPa winds

29. Estimated effect on Global Index

31. Timetable
5 November - Merge Prelim/Main model +digital filter intitialisation instead of incremental analysis update
but leave split of run until next year
12 Nov -Forecast only European Model introduced
Post November -products and downstream use developed
14 Jan - basic data assimilation
25 March- model & DA upgrade
June 03 - Declare Euromodel operational (high risk -Exeter transition)

32. New supercomputer need
Improve NWP systems:
Satellite data volumes
New Dynamics
4D-VAR
Higher resolutions
Very fine resolution mesoscale (~2km)
European Mesoscale model
Short range Ensembles
Operational Suite creaking at the seams

33. What are we getting? Initially - NEC SX-6 30 nodes
Each node has 8 CPUs sharing 64Gb of memory
Each CPU is equivalent to approx 30 T3E CPUs
Overall performance:
6x T3E’s for “performance work”
> 6x T3E’s for “throughput work”

34. And in the future In 2005 - joined by SX-6 successor: 15 nodes
Each CPU twice as powerful
Overall performance
12.5x T3Es for “performance work”
>12.5x T3Es for “throughput work”

35. Benchmark Results (N324L50)

36. The Bits IXS Met Office Networks FibreChannel NODE (8 CPUs)
IXS (Interconnect)
IXS
NODE (8 CPUs)
Gigabit Ethernet
FC Switch
Mirrored filesystems
User filesystems
FibreChannel
Front End 12xIA64
Met Office Networks

37. Timetable Installation
Bracknell SX-6
1 node system
Upgrade: 4 nodes Front end
Move to Exeter
Exeter SX-6(B)
15 node system
Exeter SX-6(A)
Acceptance tests
Sep 02 Oct 02 Nov 02 Dec 02 Jan 03 Feb 03 Mar 03 Apr 03 May 03 Jun 03 Jul 03 Aug 03 Sep 03 Oct 03 Nov 03 Dec 03
Date
T3E-A
Move to Exeter
02/09-06/10
T3E-B
17/06-22/07

38. Plans 2002- 2003 November UK Mes DA-improved covariances
December Global model & DA
January
New Dynamics in Stratospheric model
Data assimilation in Euro model
Feb-March -Global, UK mes & Euro model+DA upgrades
Transition to Exeter
Moratorium May 03 - October 03

39. Future Plans 4dVar Increased resolution Physics
Practicable global synoptic scale ready for test on new computer end 03
Inclusion physical processes 04
operational early(?) 2004
Increased resolution
40km , 50L Global; 10km , 50L Euro mesoscale
Physics
new gravity wave drag
new convection
new cloud (prognostic cloud and condensate)