Compare Observed Precipitation with that from 24 member average of ECHAM 4.5 Atmospheric Model 1976-2001 Observations and model at same resolution ~ 2.8°

Apresentação em tema: "Compare Observed Precipitation with that from 24 member average of ECHAM 4.5 Atmospheric Model 1976-2001 Observations and model at same resolution ~ 2.8°"— Transcrição da apresentação:

1 Compare Observed Precipitation with that from 24 member average of ECHAM 4.5 Atmospheric Model 1976-2001 Observations and model at same resolution ~ 2.8° x 2.8° Model: T42 horizontal; 19 vertical Onset and End of the Rainy Season in South America in Observations and the ECHAM 4.5 Atmospheric General Circulation Model Brant Liebmann Suzana J. Camargo Anji Seth Jose A. Marengo Leila M.V. Carvalho Dave Allured Rong Fu Carolina S. Vera

2 Data We wish to thank the following agencies for providing the data used in this study: Agência Nacional de Águas (Brasil) Agência Nacional Energia Elétrica (Brasil) U.T.E. Uruguay C.T.M. Salto Grande Servicio Meteorologico Nacional (Argentina, Paraguay, Uruguay) FUNCEME (Ceará, Brasil) IAPAR - SIMEPAR (Paraná, Brasil) DAEE (São Paulo, Brasil) Minesterio del Ambiente y los Recursos Naturales (Venezuela) Meteorogische Dienst Suriname METEO-France ASANA (Bolivia)

3 Annual Total Precipitation

4 Difference in Annual Total (model minus observations) What is the cause of the bias in annual totals?

5 A = ‘Anomalous Accumulation’ R = daily rainfall = Annual daily average

6 start end length

7 Jun AprMayMarFebJan Dec NovOctSepAugJul Average Onset Date

8 Length of Rainy Season

9 Model Length Minus Observed Length

10 SACZ 45W, 15S

11 Improvement or Worsening by Substitution

12 by Wet Season Length OBSERVATIONS Variance of Annual Total Explained: by Wet Season Rate

13 Conclusions Rainy season expands northward from southern Amazon ECHAM 4.5 in qualitative agreement with observations Bias in annual totals often results from differences in rain rate