1. J. Helmert and G. Vogel Deutscher Wetterdienst
Revision of the SVAT model TERRA in the COSMO model based on the validation of TERRA standalone
J. Helmert and G. Vogel
Deutscher Wetterdienst

2. Background
Adaption of improvements in TERRA standalone (F. Ament - ZMAW University Hamburg) into COSMO code
Incorporation of enhanced external parameters (min. stom. resistance, emissivity, NDVI climatology, clim. soil temperature)
Adaptions of look-up tables (ensure backward compatibility)
Impact of adaptions in TERRA on soil moisture analysis (SMA) in COSMO-EU (DWD) has to be considered

3. Simulations with TERRA standalone

4. warm temperate, fully humid, warm summer (Cfb)
Lindenberg/D
Bondville/USA
Tongyu/China
812 mm/a
2003
375 mm/a
2003
312 mm/a
2003
snow, fully humid, hot summer (Dfa)
warm temperate, fully humid, warm summer (Cfb)
snow, winter dry, hot summer (Dwa)
CEOP sites

6. Tested options and assumptions
Reference conditions for different soil types (sand, silty sand, loamy sand, sandy loam and loam)
Impermeable lower hydrological boundary (“rigid lid”)
Ground water as lower boundary condition
Depletion of root density with depth
Bare soil evaporation according to Noilhan & Planton (1989)
Reduction of root depth (0.2m)
Revised parameterization of infiltration allowing higher infiltration rates
Moisture drainage and diffusion parameterization according to Brooks & Coorey (DWD soil types)
Soil heat conductivity does not depend on soil moisture
Satellite derived LAI and plant cover (climatolo- gical annual cycle)
Variation of surface roughness
Variation of stomatal resistance and wilting point
Tested options and assumptions
… and various combinations of them

7. CEOP Lindenberg (Falkenberg) 2003
„Rigid lid“
Soil moisture
(27- 81cm)
Routine RL GW
ke_soil_hy
ke_soil_hy
ke_soil_hy PV
CEOP Lindenberg (Falkenberg) 2003
reference run (v4.0)
measurement
experimental run

8. „Root depletion with depth“
(27- 81cm)
Soil moisture
CEOP Lindenberg (Falkenberg) 2003
reference run (v4.0)
measurement
experimental run

9. „Bare soil evaporation according to Noilhan & Planton (1989)“
(3 - 9cm)
Soil moisture
CEOP Lindenberg (Falkenberg) 2003
reference run (v4.0)
measurement
experimental run

10. CEOP Lindenberg (Falkenberg) 2003
Bowen ratio =
Sensible heat flux
Latent heat flux
Similar improvement also achieved in 2004 – 2006 !

11. Bondville (USA) 2003
Tongyu (China) 2003
Cropland site (corn)
Grassland site

12. Impact of ground water compared to rigid lid
Soil moisture (3 – 9cm)
2003
2004
2005
Constant groundwater (lowbound=3)
vs.
Rigid lid lowbound=2 (reference)
Falkenberg
2006
2007
2008
moreover
Bare soil evaporation (Noilhan & Planton)
Root depeletion with deth (rootdep=0,70m)
satbased LAI +plcov

13. Impact of ground water compared to rigid lid
Soil moisture (9 – 27cm)
2003
2004
2005
Constant groundwater (lowbound=3)
vs.
Rigid lid lowbound=2 (reference)
Falkenberg
2006
2007
2008
moreover
Bare soil evaporation (Noilhan & Planton)
Root depeletion with deth (rootdep=0,70m)
satbased LAI +plcov

14. Impact of ground water compared to rigid lid
Soil moisture (27 – 81cm)
2003
2004
2005
Constant groundwater (lowbound=3)
vs.
Rigid lid lowbound=2 (reference)
Falkenberg
2006
2007
2008
moreover
Bare soil evaporation (Noilhan & Planton)
Root depeletion with deth (rootdep=0,70m)
satbased LAI +plcov

15. Impact of ground water compared to rigid lid
Bowen ratio (09-16UTC)
2003
2004
2005
Constant groundwater (lowbound=3)
vs.
Rigid lid lowbound=2 (reference)
Falkenberg
2006
2007
2008
moreover
Bare soil evaporation (Noilhan & Planton)
Root depeletion with deth (rootdep=0,70m)
satbased LAI +plcov

16. COSMO-EU Experiments

17. COSMO-EU Experiments – Properties and Goals
Start : #6795 (w/o SMA,HeatCond); #7004 (SMA, HeatCond)
Incorporation of enhanced external parameters (min. stom. resistance, emissivity, NDVI climatology, clim. soil temperature)
Adaptions of look-up tables (ensure backward compatibility)
Impact of adaptions in TERRA on soil moisture analysis (SMA) in COSMO-EU (DWD) has to be considered
Bare soil evaporation after Noilhan and Platon, 1989 (BS) - former Dickinson, 1984
Non-uniform root distribution (RD)
Ground water with upward diffusion
HeatCond: Soil moisture dependent heat conductivity (#7004)

18. EXP 6795 Soil moisture 2009031700 Reference Soil moisture [mmH2O]
Layer 3cm-9cm
Difference: Reference – Experiment [mmH2O]

19. EXP 6795 Soil moisture 2009031700 Reference Soil moisture [mmH2O]
Layer 27cm-81cm
Difference: Reference – Experiment [mmH2O]

20. EXP 6795 2m-Temperature 2009031700 Reference 2m-Temperature [degC]
Difference: Reference – Experiment [K]

21. Verification

22. Bias 00 UTC Runs
#6795

23. Quality 00 UTC Runs
#6795

24. Bias 12 UTC Runs
#6795

25. Quality 12 UTC Runs
#6795

26. Bias 00 UTC Runs
#7004

27. Quality 00 UTC Runs
#7004

28. Bias 12 UTC Runs
#7004

29. Quality 12 UTC Runs
#7004

30. Experiments at MeteoSchweiz
Thanks to J.-M. Bettems and P. Kaufmann

31. Experiments Verification Domains 47c
Test suite (COSMO modification 47c) with improved soil model
opr
Operational analysis (COSMO modification ), reference -7
COSMO suite coarse resolution with 6.6 km grid spacing, 393 x 338 grid points -2
COSMO suite fine resolution with 2.2 km grid spacing, 520 x 350 grid points
Verification Domains
Domain
Single Versions
Comparisons
47c-7
opr-7
47c-2
opr-2 -7 -2 eu
opr/47c-7
alps
opr/47c-2 ch

32. Timeseries of T_2M and TD_2M

33. Comparison of diurnal cycle
T_2M

34. Comparison of diurnal cycle
TD_2M

35. + + better ~ neutral - worse Parameter Score 47c 7 2 eu ch alps PS ME
PS, PSML: The test versions 47c  shows a similar pressure bias as the reference version, with only few stations within the alps showing a slightly larger positive bias. The standard deviation is also almost identical. For the reduced pressure, the results are even closer between the two versions. T_2M: The temperature is generally higher in 47c, leading to a more positive bias at the vast majority of the stations, and to less negative bias only at stations north and south of the Alps. The negative bias within the Alps remains or is even more pronounced at particular stations. The standard deviation is very similar for test and reference. TD_2M: The dewpoint temperature bias is switching from an overestimation (wet bias) to an underestimation (dry bias) at most inland stations. The impact on the standard deviation is neutral  with only a moderate increase at few stations in the Alps. FF_10M: The wind speed is generally increased, increasing the positive wind speed bias at many sites but decreasing the negative bias in the mountains. The impact on the standard deviation is neutral. CLCT: The cloud coverage  bias is similar in the test version 47c as in the reference. The impact on the standard deviation is small. TOT_PREC: The positive precipitation bias of COSMO-7 is slighly reduced at few stations in the Alps only, but very similar everywhere else and also similar for COSMO-2. The standard deviation and frequency bias are all similar.
Parameter
Score
47c 7 2
 eu 
 ch 
alps PS ME ~ +
STD
T_2M -
TD_2M
FF_10M
CLCT
FBI 30%
FBI 80%
TOT_PREC
+ better
~ neutral
- worse

36. Summary & Outlook
Adaption of improvements in TERRA standalone (F. Ament - ZMAW University Hamburg) into COSMO code
Comparison and verification of experiments at DWD and MeteoSchweiz
Incorporation of enhanced external parameters (min. stom. resistance, emissivity, NDVI climatology, clim. soil temperature)
Adaptions of look-up tables (ensure backward compatibility)
Impact of adaptions in TERRA on soil moisture analysis (SMA) in COSMO-EU (DWD) has to be considered
Consideration of T_2M and TD_2M Bias – wrong effect from right reasons?