hirlam-6 plan and work mou, motivations, targets data assimilation, 3d-var and 4d-var observation...
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HIRLAM-6 plan and work • MoU, Motivations, Targets
• Data assimilation, 3D-VAR and 4D-VAR
• Observation usage
• Parameterisation
• Dynamics
• System and embedding
• Lead Centre for RCR
• Météo-France agreement
HIRLAM-6 Memorandum of Understanding
• Targets– achieve highest possible accuracy for severe weather and
of wind, precipitation and temperature
– develop 3D/4D-VAR further and its use of non-conventional data
– maintain the regular analysis/forecasting cycle
– continue development of synoptic model 10-20 km
– develop meso-scale non-hydrostatic operational model with suitable physical parameterisation
– Overhaul of complete System
– develop methods for probabilistic forecasting
– continue development of verification methods
HIRLAM-6 organisation
HIRLAM CouncilAdvisory Comittee
Project Leader
Data Assimilation algorithms
Model physics System
Core group members (8)Staff (14)
Heads of Research
Model dynamics
Management Group : Project Leader : Area leaders : System ManagerData Assimilation observation usage
Overhaul leader
Module responsibles
HIRLAM strategy - synoptic• Synoptic model, 10-20 km, every 6 hours -> 2 (3) days,
4D-VAR and satellite data over a (fairly) large area– provides comprehensive set of forecast parameters for
applications and driving other models
– boundary conditions and tight coupling to meso-scale model
– covers window between ECMWF forecasts - more recent observations and boundaries (frames)
HIRLAM strategy - meso-scale• Meso-scale data assimilation and model , 2-3 km non-
hydrostatic model +3-12 (24 h)– physics for 2km, explicit convection
– turbulence and radiation non-local (later, ~ 1 km )
– rapid update cycle, vast amount of regional data available, conv/non-conv, reflectivity, precipitation ..
– 4D-VAR /3D-VAR FGAT - if in short time - spinup?
– Boundary field impact, transparent boundary cond.
Experiences and plans elsewhere:– 4D-VAR moisture and non-linear effects ECMWF
– UK Workshop Reading 2003, 4D-VAR or EnsKF at 1-3 km - no known balances at this scale !
– JMA ….
• Data Assimilation– 3D-VAR improvements
• FGAT implemented
• improved quality contr & background constraint (horizontal variation)
• flow dependency - Eady index - estimation (D. Dee)
– 4D-VAR developments• semi-Lagrangian dynamics, SETTLS, gain x 3
• incremental (and multi-) code implemented
• MF regularised physics (Buizza used mainly so far)
• Data Assimilation (cont)– Surface analysis
• tuning , new statistics)
• snow (OI)
• new data sources for physiography
• soil moisture and temperature (variational, ELDAS)
• Observation usage:– Conventional data
• Quality control and monitoring
• Tuning of observation errors
– Non-conventional data• ATOVS
– AMSU-A: bias correction, tuning
– EUMETSAT ATOVS Re-transmission Service
– land/ice, HIRS and AMSU-B
– Ts, emissitivity control variables
• Non-conventional data (cont)– Quikscat ambiguous winds
• implementation
– Radar winds assimilated• radial wind super-obs, de-aliasing, QC
• VAD winds, European exchange OPERA
– GPS ZTD prec. Water content
– Profilers -• impact study done - monitoring, blacklist needed
– SSM/I , MODIS
• Forecast model physics– Turbulence scheme
• revised stable formulation
• moist conservative scheme– total water potential temperature for the Ri
• coupling with condensation– statistical cloud scheme
• Forecast model physics (cont)– clouds and condensation
• cloud scheme - statistical - planned in turbulence
• micro physics will be worked on later
• RK or STRACO large scale condensation
– surface scheme ISBA• esat over snow
• soil freezing implemented
• new snow model to be implemented very soon
• new databases - ECOCLIMAP
Snow scheme in ISBA main modifications to original code:
• Only new snow scheme on fractions 3 and 4• Force-restore formulation replaced by heat conduction• Heat capacity of uppermost layer replaced by 1 cm moist soil.• A second soil layer (7.2 cm)• Forest area decreased so that at least 10% of area is low-vegetation• At present (temporarilly!) no soil freezing• Forest tile, no modifications
Tclim
ISBA: snow covering parts of fractions 3 and 4
Td snow
Td 3 and 4Ts2 snow
Ts2 3 and 4
Ts snow Ts 3 and 4T
snow
Thermally active layer
snow in beginning of timestep Snow change
mixing of T in soilbetween timesteps
Features of the snow scheme:
• move the snow from fractions 3 and 4 to fraction 6 every timestep
• one layer of the snow, with a thermally active layer < 15 cm
• water in the snow, which can refreeze
• varying albedo and density
• mirroring of temperature profile in the ground to assure correct memory
• Forecast model physics (cont)– Convection
• STRACO developments implemented
• Kain-Fritsch code as an option - then tested
– Radiation scheme / updates
– Sub grid scale orography• implement later - after turbulence changes
• alternative, orographic turbulence
• Model Dynamics– Time integration
• Semi-Lagrangian updates, Ritchie-Tanguay T equation
• Semi-Lagrangian and physics coupling, Wedi
– NH model• semi-Lagrangian version (Tartu)
• physics for meso-scale will be provided
• testing and compare external model (under discussion)
– Boundary conditions• Improve current boundary scheme
• Research and development of schemes for transparent boundary conditions
– Digital filter initialisation• Launching (forward), reduced spin up
• Incremental version and spin-up studies
• Blending
– Forecast probabilities• LAMEPS (ECMWF perturbations) - near real time trial
• (LAM singular vectors ?)
• System and Embedding:– implementing developments – testing of the beta-releases -> Reference
– Regular Cycle of Reference system - validation - FMI RCR
– Efficiency and Overhaul of System - limited work
– Verification methods - development - Workshop 2004
– Communication and documentation - HeXNeT
• Scientific documentation, Paper planned
Lead Centre for Regular Cycle with the Reference• FMI / HIRLAM agreement
– FMI runs the Reference System as operational model
– Is the RCR of HIRLAM-6
– Operational attention and support for RCR
– Reference system at 0.2/40, reference settings and obs
– RCR products in near real time on HeXNeT
– Not operational status but high level of support
– Full data set on HeXNeT available to all HIRLAM
– Very limited deviations (ice ,SST), available to all
– emergency changes
• Procedures for upgrades– proposed beta release tested 4x4 weeks– parallel run at FMI < 2 months– agreement between FMI and MG– Core group support for solving problems
• travel funds within the Budget
– up to 2 Reference releases per year
• Monitoring– Operational forecasters in real time on HeXNeT– Automatic near real time displays of obseravations
and fields– Monthly monitoring reports , observations, fields,
errors, diagnostics, profiles
Météo-France agreement• 3D-VAR• Observations, conventional, radar , TOVS• Surface• Turbulence• Orographic drag• Convection at intermediate scales (-)• 4D-VAR simplified physics (-)• Physics - dynamics interface • Radiation scheme ?• NH dynamics ??• Near real time intercomparisons ?• Diagnostics and verification
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