Ss. Vaidya et Ss. Singh, Applying the Betts-Miller-Janjic scheme of convection in prediction of theIndian monsoon, WEATHER FOR, 15(3), 2000, pp. 349-356
The performance of the Betts-Miller-Janjic scheme of convection has been in
vestigated for prediction of the Indian monsoons. For this purpose a limite
d area numerical weather prediction model with two schemes of convection, o
ne with the Betts-Miller scheme and other with the Betts-Miller-Janjic sche
me, is run for five cases of monsoon depression that made landfall over the
Indian coast. The results from the two schemes are compared.
Detailed analyses of mean sea level pressure, wind, and rainfall have shown
that the Betts-Miller-Janjic scheme has considerably improved the rainfall
prediction over the Indian landmass and improvement is also seen in the me
an sea level pressure Fields and cyclonic circulation associated with the d
epression at the 850-hPa level. The forecast results are further verified b
y computing the root-mean-square errors, and the difference in the skill sc
ores between the two model runs are tested for their statistical significan
ce. It is found that the Betts-Miller-Janjic scheme has a statistically sig
nificant effect on the model skill beyond 24 h, with maximum impact on mean
sea level pressure and geopotential height.