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

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

Simulations with TERRA standalone

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

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

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

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

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

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

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

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

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

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

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

COSMO-EU Experiments

COSMO-EU Experiments – Properties and Goals Start 2009030100: #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)

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

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

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

Verification

Bias 00 UTC Runs #6795

Quality 00 UTC Runs #6795

Bias 12 UTC Runs #6795

Quality 12 UTC Runs #6795

Bias 00 UTC Runs #7004

Quality 00 UTC Runs #7004

Bias 12 UTC Runs #7004

Quality 12 UTC Runs #7004

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

Experiments Verification Domains 47c Test suite (COSMO modification 47c) with improved soil model opr Operational analysis (COSMO modification 858 - 866), 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 47c-7@eu opr-7@eu opr/47c-7 alps 47c-2@alps opr-2@alps opr/47c-2 ch 47c-7@ch opr-7@ch 47c-2@ch opr-2@ch

Timeseries of T_2M and TD_2M

Comparison of diurnal cycle T_2M

Comparison of diurnal cycle TD_2M

+ + 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

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?