1. Summer Colloquium on the Physics of Weather and Climate ADAPTATION OF A HYDROLOGICAL MODEL TO ROMANIAN PLAIN MARS (Monitoring Agriculture with Remote Sensing) project cooperation with CIRAD France Elena SAVIN, Gheorghe STANCALIE, Corina ALECU National Institute of Meteorology and Hydrology Bucharest

2. Summer Colloquium on the Physics of Weather and Climate ROMANIA - geographical position East Europe - climate: temperate: annual mean temperature 10 C precipitation (400 - 700 mm/year) - cultivated surface : 20 000 ha

3. Summer Colloquium on the Physics of Weather and Climate Demand from: minister and trade - product estimation for cultivated areas for wheat and maize Solution: adaptation of a simple water balance model - BIPODE Possibilities - many models Limitations - available data steps: adaptation for station surface yield estimation

4. Summer Colloquium on the Physics of Weather and Climate INPUT DATA OUTPUT DATA meteo : mean daily temperature (C) maximum evapotraspiration (mm) relative humidity (%) real evapotraspiration (mm) sun shine duration (hours) ETR/ETM ratio (%) wind speed (m/s) water amount for irrigation plant: type (white, maize) phenological phases duration sowing date crop coefficient root growing rate (cm/day) soil: type ADAPTATION : field capacity at 1 m- crop coefficient water content at sowing date at 1 m - root growing rate - ETP daily values

5. Summer Colloquium on the Physics of Weather and Climate Algorithm used by BIPODE 1. Ru = 0 if P<Pth Ru = Kr *Pth ifP>Pth 2. Peff = P-Ru 3. Dr = 0 if Peff+Wa z-1 <AWC Dr = AWC - (Peff+AWC z-1 ) SOIL reservoir 1m 4,5,9 DR 3 RU, 1 ETR, 8 ETM, 7 ETP, Kc P Kr, Pth AWC 5 AWCr Z, RGR Peff, 2 HR, 6 input data output data 4. WAz = Peff - Dr + WAz-1 on entire profile 5. Knowing the day (z) and the root growth rate (RGR) AWCr and War were determined 6. HR = Awrz/AWCr 7. ETM = Kc*ETP 8. ETR = f(ETM,HR) 9. Awz = Peff - Dr - ETR + Awz-1

6. Summer Colloquium on the Physics of Weather and Climate CROP COEFICIENTS Phenological phases - mean from 170 data sets for wheat and 101 for maize

7. Summer Colloquium on the Physics of Weather and Climate The best correlation yield - IR (obtained from 60 data sets - wheat 30 data sets - maize) IR=(ETR/ETM) flowering *(ETR) vegetative period Estimation of yield after flowering (ETR/ETM) from model (ETR) vegetative period - mean from 10 years

8. Summer Colloquium on the Physics of Weather and Climate Models Vs. observation for wheat (29 data sets)

9. Summer Colloquium on the Physics of Weather and Climate - Romanian plain was classified in 6 homogenous zones (soil, climate, agro) - for 4 zones the correlation coefficient increases - for 2 zones the correlation coefficient decreases (hills zones) - temperature influence - yield was estimated for station and integrated for cultivated surface

10. Summer Colloquium on the Physics of Weather and Climate Data Spatialisation grid 20 km x 20km - data set associated (interpolation of missing input data) - use of data estimated from NOAA-AVHRR satellite images - spatial data - repetivity (4 images / day)

11. Summer Colloquium on the Physics of Weather and Climate NOAA - AVHRR images channel 1(visible) channel 2(NIR) channel 3(MIR) channel 4 channel 5 (IR thermal) =0.58-0.98  m =0.72-1  m =3.55-3.9  m =10.3-11.3  m =11.5-12.5  m

12. Summer Colloquium on the Physics of Weather and Climate Image reception hrp format Image import ERDAS Imagine:  Data calibration for AVHRR channels 1, 2, 3 in radiance or albedo values 4, 5 in temperature  geometric corrections Image Process ERDAS Imagine:  Reprojection NDVI Surface temperature actual evapotranspiration surface emissivity albedo

13. Summer Colloquium on the Physics of Weather and Climate NORMALISED DIFFERENCE VEGETATION INDEX CHANEL 2 - CHANEL 1 NDVI = --------------------------------- CHANEL 2 + CHANEL 1 CANAL 2 - near infrared radiation CANAL 1 - visible radiation LEGEND < 1 0.1 0.2 0.3 0.4 0.5 0.53 NDVI 12 June 2000 Reflectance for green leafs wavelength (um) Reflectance for vegetation and soil wavelength (um) 0.4 0.5 0.6 0.7 0.8 0.9 0.4 0.6 0.8 1.2 1.4 1.6 1.8 2 2.2 2.4 2.6 2.8 soil green grass dry grass blue greenred near infrared visible near infrared

14. Summer Colloquium on the Physics of Weather and Climate NORMALISED DIFFERENCE VEGETATION INDEX - daily values NORMALISED DIFFERENCE VEGETATION INDEX - daily values 22 June - 26 June 2000 and 5 days value obtained by MAXIMUM VALUE COMPOSITE

15. Summer Colloquium on the Physics of Weather and Climate Broad band ALBEDO obtained from the combination of albedo values for channels 1 and 2 Broad band ALBEDO obtained from the combination of albedo values for channels 1 and 2 6 June 2000 d = bo+b1*a1 + b2*a2 where: a1,a2 albedo values for channels 1,2 bo, b1 si b2 coefficients b1 = 0.494*NDVI 2 - 0.329*NDVI + 0.372 b2 = -1.437*NDVI 2 + 1.209*NDVI + 0.587 0.05-0.1 0.1-0.2 0.2-0.3 0.3-0.4 clouds Legend

16. Summer Colloquium on the Physics of Weather and Climate SURFACE EMISSIVITY 12 June 2000

17. Summer Colloquium on the Physics of Weather and Climate SURFACE TEMPERATURE 6 June 2000 split window method

18. Summer Colloquium on the Physics of Weather and Climate ACTUAL EVAPOTRASPIRATION 1 2 3 4 5 5.2 FOREST ETR (mm) ACTUAL EVAPOTRANSPIRATION ESTIMATED FROM NOAA-AVHRR image 12 June 2000

19. Summer Colloquium on the Physics of Weather and Climate SURFACE TEMPERATURE (covered with vegetation) split-windows method 20 June 1999 22 June 2000

20. Summer Colloquium on the Physics of Weather and Climate NDVI - 4 April 2001 Surface emissivity 4 April 2001

21. Summer Colloquium on the Physics of Weather and Climate Surface temperature (covered with vegetation) 4 April 2001 Actual evapotranspiration 4 April 2001

22. Summer Colloquium on the Physics of Weather and Climate CONCLUSION 1. For 3 years estimated yield was  200 kg/ha to the real yield 2. Adaptation of the improved water balance model for yield forecast 3. Validation of data obtained from NOAA-AVHRR images using measured data 4. Estimation of : LAI (leaf area index) FPAR (photosinteticaly active radiation) 5. Use of data obtained from NOAA-AVHRR images in the model