Development of a European Land Data Assimilation System

(ELDAS)Combined

Research/Demonstration project EU 5th framework

Motivation

• Pilot study, to combine (European) expertise on soil moisture assimilation

• Provide a European contribution to GLDAS research

• Prepare/apply use of satellite data for soil moisture assimilation – MSG: thermal/visible– SMOS: microwave

Partners

SMHI

CEH Wallingford

ECMWF

Vienna Univ

INM Madrid

KNMI

AlterraWageningen

Univ Bonn

DWD/GPCC

CNRM

Plus User Advisory Board

Design of assimilation system

precipitation

radiation

evaporation

Soil moisturecorrection scheme

Soil moisturecontent

(sub)surfacerunoff

Observations drivingsoil moisture correction

Synops dataMETEOSAT or

MSG

Land surfaceparameterizationscheme

Boundary layerscheme

Observations: precipitation

Raw radar data

Observations: precipitation

Corrected radar data

Observations: precipitation

Interpolation to ELDAS grid

Observations: precipitation

Blend with gauge data

ELDORADO LW & SW Radiation

• Simple data assimilation of METEOSAT TOA products in NWP RT model

• Verified against BSRN & local SW networks

Impact of forcings

580 585 590 595 600 605August 2000

286

288

290

292

294

296

2m te

mpe

ratu

re [K

]

OBSCTRLEKFNO FORCNO PRECNO RAD

2 7 12 17 22 27August 2000

282

284

286

288

290

2m d

ewpo

int

tem

pera

ture

[K

]

OBSCTRLEKFNO FORCNO PRECNO RAD

T

Td

Loobos, NL

Trial assimilation of surface heating rates

(Murex)

160 180 200 220 240 260 280julian day

15

20

25

30

da

ily m

ea

n r

oo

t zo

ne

so

il m

ois

ture

[%]

ObsCtrlEKF assim. T,RH,SHREKF assim. T,RHEKF assim. SHR

Corr. Bias RMS0.94 3.46 2.000.81 0.89 2.440.79 0.97 2.530.94 2.95 1.58

Soil

moi

stur

e

Days when SHR is available (50% data missing, 25% cloudy)

+ observations-- control-- only SHR assimilated-- only T & RH assimilated-- all assimilated

Assimilation of -wave data (SGP97)

170 175 180 185 190 195julian day

0.2

0.4

0.6

0.8

1.0

evap

orat

ive

frac

tion OBS

CTRL

KFTR

KFTRB

KB

T & RHAll dataTb only

Validation sites

Validation sites

Validation sites• 20yr ‘PILPS’-climatology (driven by ERA40)• 15mnth CTL with obs P & R• 15mnth DA with obs P & R

Effect of data assimilation

One of dW

Accumulated increment

Change of evaporation

Change of runoff

Change of soil water

…and for various classes

Classic Mediterranean

Frozen ground Irrigation (?)

Use of increments to change evaporation

Froze

n g

rou

nd

Classic

Mediterranean

Irri

gati

on

(Atmospheric) constraint of evaporationClassic Mediterranea

n

Frozen ground

Irrigation (?)

PrecipitationRunoffStorageEvaporation

Dealing with increments in ERA40 hydrological budget

analysis1. Subtract I from runoff2. If runoff < 0, compensate with dW

Dealing with increments in ERA40 hydrological budget

analysis1. Subtract I from runoff2. If runoff < 0, compensate with dW

Wrap up

• Infrastructural developments are involved

• Demo & Validation in progress• Analysis of analyses: fairly

inefficient in terms of changing evaporation– Calls for adjustment of E/W

instead of W

Final Workshop

• 8-11 nov 2004• ECMWF, Reading