Relationship of tropospheric temperature anomaly with Indian southwest monsoon rainfall

The statistical relationship between the Indian southwest monsoon rainfall over all India (AIR), northwest India (NWR) and peninsular India (PIR) and tropospheric temperature (TT) anomaly over seven selected Indian stations between 300 and 850 hPa has been examined for the period 1961-1990. The study is furthered by means of sliding 15 years correlation coefficients. The results indicate that the previous May's tropospheric temperature anomaly has a strong and direct relationship with southwest monsoon rainfall, suggesting that warmer/colder tropospheric temperature in May leads to good/bad southwest monsoon rainfall over India. The correlations are stronger for AIR and NWR followed by PIR. Its stability analysis displays best correlation during 1967-1981 and 1968-1982 and again during the recent years 1975-1989 and 1976-1990 for all the regions. Significant direct correlations are also obtained with the tropospheric temperature anomaly of the previous April and spring season. The result also suggests that antecedent May tropospheric temperature anomaly may be useful in the long range prediction of the following southwest monsoon rainfall over India. (C) 1998 Royal Meteorological Society.