TY - JOUR
T1 - Impact of different initial soil moisture fields on Eta model weather forecasts for South America
AU - de Goncalves, L. Gustavo Goncalves
AU - Shuttleworth, William James
AU - Chou, Sin Chan
AU - Xue, Yongkang
AU - Houser, Paul R.
AU - Toll, David L.
AU - Marengo, José
AU - Rodell, Mathew
PY - 2006/9/16
Y1 - 2006/9/16
N2 - Two 7-day weather simulations were made for South America in July 2003 and January 2004 (in the Southern Hemisphere summer and winter) to investigate the impacts of using different soil moisture initialization fields in the Eta model coupled to the Simplified Simple Biosphere (SSiB) land surface model. The alternative initial soil moisture fields were (1) the soil moisture climatology used operationally by the Centro de Previsão do Tempo e Estudos Climáticos in Brazil and (2) the soil moisture fields generated by a South American Land Data Assimilation System (SALDAS) based on SSiB. When the SALDAS soil moisture fields were used, there was an increase in the model performance relative to climatology in the equitable threat score calculated with respect to observed surface precipitation fields and a decrease (up to 53%) in the root-mean-square error relative to the NCEP analysis of the modeled geopotential height at 500 hPa and mean sea level pressure. However, there was small change in the model skill in positioning the primary South American weather systems because of a change in the upper troposphere circulation caused by SALDAS initialization, most noticeably in the South Atlantic Convergence Zone.
AB - Two 7-day weather simulations were made for South America in July 2003 and January 2004 (in the Southern Hemisphere summer and winter) to investigate the impacts of using different soil moisture initialization fields in the Eta model coupled to the Simplified Simple Biosphere (SSiB) land surface model. The alternative initial soil moisture fields were (1) the soil moisture climatology used operationally by the Centro de Previsão do Tempo e Estudos Climáticos in Brazil and (2) the soil moisture fields generated by a South American Land Data Assimilation System (SALDAS) based on SSiB. When the SALDAS soil moisture fields were used, there was an increase in the model performance relative to climatology in the equitable threat score calculated with respect to observed surface precipitation fields and a decrease (up to 53%) in the root-mean-square error relative to the NCEP analysis of the modeled geopotential height at 500 hPa and mean sea level pressure. However, there was small change in the model skill in positioning the primary South American weather systems because of a change in the upper troposphere circulation caused by SALDAS initialization, most noticeably in the South Atlantic Convergence Zone.
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U2 - 10.1029/2005JD006309
DO - 10.1029/2005JD006309
M3 - Article
AN - SCOPUS:33847010681
SN - 0148-0227
VL - 111
JO - Journal of Geophysical Research Atmospheres
JF - Journal of Geophysical Research Atmospheres
IS - 17
M1 - D17102
ER -