Status report from the Lead Centre for Surface Processes and

AssimilationE. Rodríguez-Camino (INM)

and

S. Gollvik (SMHI)

Outline

• Next Workshop on Surface issues (4th):

• Activities at different centres

• Recent comparison and evaluation exercises

• New physiography: proposal of evaluation

• Preferent fields of activity for the near future

3rd SRNWP Workshop on surface processes and assimilation (Madrid, 22-24 Oct.2001):

short term recommendations

• Improvement of snow formulation

• Minimum number of predictive equations to describe snowpack evolution: T, H, LW, Alb

• Improvement of the snow depth analysis

• Implementation of satellite based vegetation properties in climate files

• Review of definition and use of roughness length for heat and momentum

3rd SRNWP Workshop on surface processes and assimilation (Madrid, 22-24 Oct.2001):

medium-term recommendations

• Increase the number of surface layers: 4-5

• Separate energy budget for the canopy

• Review roughness length averaging for momentum exchange

• Variational approach to soil moisture assimilation

• Use of SYNOP soil temperature for validation

• Use of satellite data for validation

• Improvement of run-off formulation

4th workshop on surface processes and assimilation:

SMHI, Norrköping around spring 2004 depending on HIRLAM

internal arrangements.

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Activities at different centres: ALADIN

Development of the SVA assimilation of soil moisture in the frame of ELDAS

Creation of a new physiographic database ECOCLIMAP: global, 1km res.

Externalization of surface package.

Organization of RhôneAggregation experiment: comparison and tuning of major European surface schemes: TESSEL, TERRA, ISBA_HIRLAM, ISBA_MF, MOSES.

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Activities at different centres:

HIRLAM (I)

Explicit treatment of soil water freezing/thawing Re-computation of background error statistics for

T2m and RH2m analyses New snow depth analysis based on OI Additional tile for snowed bare and low vegetation

surfaces (use of predictive equations for snowalbedo, density. Freezing/thawing of water retained by snow)

Assessment of the HIRLAM surface scheme by seasonal integrations and against field data: RhoneAggr, EFEDA

Subgrid run-off (consequence of RhoneAggr Experiment)

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Activities at different centres: HIRLAM (II)

Implementation and tests of the SVA assimilation of soil moisture (Balsamo) on the HIRLAM system

Tests with the new physiographic database ECOCLIMAP using HIRLAM system.

Surface analysis as nowcasting tool

RECENT COMPARISON AND EVALUATION EXERCISES

• Rhone AGGregation experiment (http://www.cnrm.meteo.fr/mc2/projects/rhoneagg/)

• ELDAS (http://www.knmi.nl/samenw/eldas/)

Rhone-AGG Experiment

Land Surface Schemes Intercomparison project- Offline simulations (Jul’86-Aug’89)- Atmospheric forcings provided- Coupled with a hydrological model (ISBA-MODCOU)

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* Participants:

CLASS Met. Service of CanadáI SBA CNRM/ Meteo-FranceMOSES Met Offi ceNOAH NOAA/ NCEP/ EMCECMWF ECMWFMECMWF KNMINSI PP NASADWD-MLSM DWDI SBA-HI RLAM I NM... ...... ...

www.cnrm.meteo.fr/mc2/projects/rhoneagg/index.html

•Land Surf ace Schemes’ I ntercomparison Project

precipitation

radiation

evaporation

Soil moisturecorrection scheme

Soil moisturecontent

(sub)surfacerunoff

Observations drivingsoil moisture correction

Synops data

METEOSAT or MSG

Land surfaceparameterizationscheme

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Development of a European Land Data Assimilation System to predict Floods and Droughts (ELDAS), (supported by the European Union in the context of the Fifth Framework Program (contract nr EVG1-CT-2001-00050). ELDAS is designed to develop a general data assimilation infrastructure for estimating soil moisture fields on the regional (continental)scale, and to assess the added value of these fields for the prediction of the land surface hydrology in models used for Numerical Weather Prediction (NWP) and climate studies.

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Project aimsIn brief, the project has the following goals:

•Combine current (European) expertise in soil moisture data assimilation, and design and implement a common flexible and practical data assimilation infrastructure at a number of European NWP-centres

•Validate the assimilated soil moisture fields using independent observationmaterial

•Assess the added value of soil moisture data assimilation for prediction of the seasonal hydrological cycle over land (associated with drought prediction) and for the risk of floodings

•Build a demonstration data base covering at least one seasonal cycle and the European continent

•Anticipate on the use of data expected from new satellite platforms, in particular METEOSAT Second Generation (MSG) and the ESA Soil Moisture/Ocean Salinity Mission (SMOS)

•Provide a European contribution to the Global Land Data Assimilation System(GLDAS), a US initiative for generating near-realtime information on land surface characteristics on a global scale

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3 planned experiments as HIRLAM contribution

REF (sequential SM assimilation)

ELD: same as REF but with soil moisture generated by CNRM forced by observed precipitation (rad. & hr not used)

SVA: same as REF but with SVA assimilation of soil moisture (Balsamo)

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Explore subgrid evolution

Possibly and depending on our resources, we’ll run a 4th experiment with tiling structure: same as REF, but including the same land tiles as in the HIRLAM reference system

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ECOCLIMAP

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ECOCLIMAP database(Masson et al., 2003)

Global and high resolution dataset (1-km). Detailed information over Europe coming from CORINE and

PELCOM projects. Use of full resolution maps of the vegetation index NDVI to

provide the appropiate temporal and spatial scales. 215 ecosystems allowing a better assignement of vegetation

parameter sets. (90 over Europe) Use of aggregation rules to derive surface parameters at the

desired model resolution and for mixed ecosystem pixels. Vegetation parameters (veg, lai, Zoh, Zom, alb, Rsmin, frac,

emis, ...) with monthly or decennial (10 days) frequency. It allows the tiling approach, as used by the HIRLAM surface

scheme.

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How to assess a new physiographic database?

• Introduce in a model and compare scores? Models are usually tuned to their climatic files! Some surface parameters are frequently tuned (e.g., Zo) and others not (e.g., veg).

• Compare against point measurements? Good, but restricted to certain land uses and climatic conditions.

• Compare against other databases? Good, but which one is the “truth”

• Compare data and algorithms used to classify ecosystems?• Locals have the best knowledge of landscape features

Distribute the evaluation work!

Preferent fields of activity for the near future

• Runoff description is rather crude (field capacity?). Use of soil moisture subgrid variability, subgrid topography, subgrid precipitation, ... RhoneAggr Exp.

• Soil moisture assimilation: comparison of different methods ELDAS

Preferent fields of activity for the near future

• Winter conditions are still a source of problems for surface schemes. A better snow description needed: a) ageing of albedo, density, emissivity, etc; b) snow albedo in forests and complex orography; c) effect of water retained by melting snow; d) freezing and melting of soil moisture, lakes; e) sea ice description.

Preferents fields of activity for the near future

• Substitution of land-use and look-up tables for vegetation parameters for directly measured (from satellite) vegetation parameters: veg, LAI, alb. The frequency of updating should also be reviewed (1 week?) ECOCLIMAP