Again, since the present document includes both the fourth progress report and the final one, the overall evolution along the four years of the network's life will be considered hereafter. A factual description is given here, since relevant arguments were discussed in parts A.1 and B.1.

The thematic partition of the research objectives into tasks was revised twice, at the end of the first and second years, in order to face :

The changes aimed both at more realism in data assimilation and coupling, at more ambition in non-hydrostatic dynamics and to a less extent in physics, and at an increased consistency. The new balance between teams (detailed in the part dedicated to the research effort of participants) and the delays in the recruitment of young researchers (see part B.5) were also considered.

These changes were submitted to the agreement of the EC around the mid-term review. The topical changes (in bold characters) to the initial work plan are recalled hereafter :

1. Theoretical aspects of non-hydrostatism (NH)
1a: Development of the vertical plane version of ALADIN, as a powerful and cheap tool for further studies in dynamics
1b: Refinement and test of a radiative upper boundary condition for hydrostatic and non-hydrostatic dynamics
1c: Improvement of the lower boundary condition
1d: Re-examination of the semi-implicit approach
Solving residual instability problems in the two-time-level semi-Lagrangian advection scheme (so as to enable larger time-steps and a correspondingly lower computing cost)
(moved from 2)
1f: Problems not yet identified

2. Case studies aspects
2a: Definition of the framework of experiments, choice of a set of reference situations
2b: Validation of the current physics and non-hydrostatic dynamics : comparison to hydrostatic dynamics, to observations, identifying problems
2c: Solving residual instability problems in the two-time-level semi-Lagrangian advection scheme (so as to enable larger time-steps and a correspondingly lower computing cost) (moved to 1)
2c: Validation of the new developments in dynamics or coupling
Validation of the refinements in physics, identifying feed-backs and residual problems

3. Noise control in high resolution dynamics
3a: Further damping of orographic resonance in semi-Lagrangian advection
3b: Improved use of the damping properties of a decentered semi-implicit semi-Lagrangian advection scheme
3c: Investigation of the potential of the predictor-corrector approach (new)

4. Removal of the thin layer hypothesis
4a: Analysis of the required modifications and coding
4b: Impact studies in the vertical plane model then on real cases

5. Coupling and high resolution modes
5a: Bi-directional coupling in spectral mode (delayed)
5a: Time-interpolation problems (new)
5b: Well posed lateral coupling in NH mode (changed in) Well posed (or transparent) lateral boundary conditions
5c: Problems of jump in resolution / domain sizes in modeling and data assimilation modes
5d: Design of a more precise method for spectral coupling

6. Specific coupling problems
6a: Blending of fields in data assimilation for preserving high resolution forecast details
6b: Tendency coupling for surface pressure and other technical variations around Davies' technique of field coupling in a buffer zone
6c: Coupling problems in variational data assimilation (moved to 11)

7. Reformulation of the physics-dynamics interface
7a: Study of the interactions between non-hydrostatic features and physical parametrisations
7b: Analysis of the problems related to a 1-dimensional physics, impact of an exact introduction of diabatic forcing
7c: Sensitivity of the physics/dynamics interface to vertical resolution

8. Adaptation of physics to higher resolution
8a: Parametrisation of the small-scale features of convection
8b: Test, retuning and improvement of the various physical parametrisation in the framework of a very high resolution
8c: Improved representation of boundary layer
8d: Introduction of slope effects (extended to)
Improved representation of orographic effects

9. Design of new physical parametrisations
9a: Implementation of a new parametrisation of turbulence
9b: Use of liquid water and ice as prognostic variables, implementation of a new micro-physics parametrisation
9c: New parametrisation of exchanges at lakes surface
9d: Improved representation of exchanges at sea surface
(merged in)
9c: New parametrisation of exchanges at sea and lake surface
9d: Improved representation of land surface, including the impact of vegetation and snow
9e: Refinements in the parametrisations of radiation and cloudiness

10. Use of new observations
10a : An efficient quality control and selection procedure for observations in a mesoscale LAM
10b: Yet unused SYNOP observations (extended to) A more extensive and accurate use of conventional data
10c: GPS and/or MSG observations (changed to)
A more extensive and accurate use of available satellite data
10c: Doppler radar observations (changed to)
10c :
The progressive use of some non-conventional data, particularly radar reflectivities
10d: METOP (IASI) observations (only in the framework of the PhD thesis of M. Szczech)

11. 3D-Var analysis and variational applications
11a: Definition and calculation of new background error statistics, impact of domain resolution and extension, identification of horizontal relevant scales (extended)
11b: Scientific investigation of the problem of the extension and coupling zone, analysis of the impact of initialization
11c: Management of observations in 3d-var: from academic single-observation experiments to the use of any available data
11d: Coupling problems in variational data assimilation, interaction with blending (moved from 6)
11e: Intensive scientific validation and improvement of 3D-Var
11f: Development of variational type applications (adjoint methods for sensitivity studies, singular vectors), as a project itself and to provide more insight into the coupling problem for 4d-Var (extended)

12. 4D-Var assimilation
12a : 3D-FGAT as an intermediate step between 3D and 4D-Var (new)
12b: Basic validation and tests
12c: Definition of a coupling strategy
12d: Scientific validation
12e: Improvement of the treatment of humidity in data assimilation

The main steps forward are compared to the initial and revised schedules in the table below. The initial milestones are in black, and the revised ones in red (update after one year) or blue (after two years).


Initial and revised milestones

Progress of the project (main steps)


Start of the project

§ First training course

· Prototype version of the 2d-model ready for NH studies

· Analytical study of orographic resonance, tests

· Preliminary design of predictor/corrector scheme

· Search for new time-interpolation methods for LBCs, or new coupling schemes

· Analytical study for relaxing the thin layer hypothesis

· Test of new descriptions of sea and lake surfaces


¨ Start of 3 PhD & 1 Post-Doc studies

· Scale-selection strategy for 3d-var defined


¨ Start of 1 PhD study

· First results on orographic forcing at small scales


· Identification of stability problems in semi-implicit NH

· Framework for validations at very high resolution ready; first tests

· Improvement of the 1d-model, for the validation of new developments in physics

· Prototype version of blendvar (combination of 3d-var and blending)

· Starting validation of the singular vectors computation


1st annual report

¨ Start of 1 Post-Doc study

· First proposals for new NH variables

· Operational version of blending


ä reference high resolution NH version ready
ä 3d-var analysis ready
ä first set of observation operators ready

ä reference high resolution NH ready
ä mixed 3d-var / blending assimilation ready for first parallel tests

§ Second training course

¨ Start of 2 PhD studies

· Prototype version for coupling the surface pressure tendency

· First version of a prognostic convection scheme available


¨ Start of 2 PhD & 1 Post-Doc studies

· New proposals for NH variables

· Starting the design of new validation tools

· Major changes in the description of boundary layer

· First evaluations of 3d-var assimilation on real cases


¨ Start of 1 PhD study

· Restart of the work on radiative upper boundary condition

· New description of snow cover ready

· Starting an in-depth update of radiation scheme

· Starting work on the use of standard observations at high resolution and small domains

· Evaluation of simplified physics (for use in 4d-var) at small scales, using variational tools


Mid-term review

ä reference high resolution NH version fully validated with improved coupling
ä prototype version of 4d-var ready

ä reference high resolution NH version fully validated, with an appropriate coupling strategy and an improved physics
ä development of new observation operators started.

· "Functional boxes" approach for handling liquid water and ice working


§ Third training course


· Skill of blending and blendvar demonstrated on a well-documented case study

· First use in ALADIN of "humidity bogus" observations, derived from satellite imagery


· Skill and efficiency of the ALADIN-NH dynamics demonstrated through a comparison to other "competing" choices, on academic test cases

· First parallel 3d-var suite in Budapest

· Use of raw satellite data in ALADIN

· Positive results with spectral coupling

· 4d-screening, first step of 3d-FGAT, ready but significant cost problems encountered


· New semi-implicit operator for NH dynamics, leading to an enhanced stability

· Start of an extensive use of the adjoint model for sensitivity studies, focussing on (simplified or full) physics


3rd annual report

ä operational implementation(s) of an update of the «reference version»
consistent data assimilation ensemble ready for operational implementation up to 3d-var
well defined strategy for the assimilation of humidity at fine scales available.

ä stable and efficient NH dynamics validated on academic and real case studies
ä improved surface description operational
ä new coupling strategy ready
ä pre-operational data assimilation suites including 3d-var, blending, improved O.I. for surface, and use of more observations
ä prototype version of 3d-FGAT

· First encouraging results on the new "prognostic self-adaptative" convection scheme


¨ First ALATNET PhD defense : Gianpaolo Balsamo


· The NH-version of ALADIN is chosen as the dynamical core of the future successor of ALADIN (for very high resolutions, 2-3 km). The 3d-var version of ALADIN is confirmed as data assimilation vector for the same project (before going to 3d FGAT and 4d-var).


· Proposal for a new coupling/blending strategy in 3d-var

· Emergence of a new strategy for radiation

· First use of new satellite observations at high resolution in ALADIN

· Design of a work plan for using of radar data

· Simple temporary solution for the lower boundary condition in NH dynamics


¨ Fourth ALATNET seminar

· Expression of interest of the HIRLAM consortium for the ALADIN NH dynamics

· Start of SREPS based on ALADIN and singular-vectors computations in Budapest

· New warning index to monitor coupling strategy

· First results on orographic forcing : impact of resolution on the behaviour of parametrisations, more exact representation of drag and lift effects


End of the project

ä completion of the whole programme.

ä completion of the whole programme in dynamics and coupling, of most items in physics ;

ä 3d-FGAT ready for operational application (instead of 4d-var, till at prototype level) and not with the targeted observations.


¨ Second ALATNET PhD defense : Cornel Soci


4th annual
and final reports

· Fully validated and cleaned version of NH dynamics

· Agreement for an enhanced cooperation between the ALADIN and HIRLAM consortia

The partition of the research and training effort between the five partners, as concerned raw figures, is detailed in part B.4 (assessment of network management and benefits). Their respective involvements in the main 12 research topics is summarized hereafter, while the part of networking for each scientific issue is discussed in part B.4.

Research topic

Lead centre

Other centres (1)

Contributions (2)


P3 (Prague)

P1, P4, P2, P5

P1, P3


P5 (Ljubljana)

P1, P3, P4, P2

P1, P3, P5


P3 (Prague)


P1, P3


P1 (Toulouse)




P5 (Ljubljana)

P1, P3, P4

all partners


P3 (Prague)

P1, P4, P5

all partners


P2 (Brussels)

P1, P3, P5

P1, P2, P3


P2 (Brussels)

P1, P5

P1, P2, P3, P5


P1 (Toulouse)

P2, P3, P4, P5

all partners


P1 (Toulouse)

P3, P4, P2, P5

P1, P3, P4


P4 (Budapest)

P1, P3

P1, P2, P3, P4


P1 (Toulouse)


P1, P4

(1) Partners likely to contribute in the initial proposal, ordered by decreasing participation
(2) Following the partners ordering.