Surface temperature pattern of the Indian Ocean before summer monsoon

Abstract

The surface meteorological data collected during 1963 and 1964 indicate that the northward migration of the ITCZ is associated with a shift of the warm waters to the northern Indian Ocean. The warmer waters, found in the equatorial regions during the northern winter, shift northward during spring and this shift is completed by the end of May, the beginning of the summer monsoon. The shifting of the warm water pool from winter till the beginning of the summer monsoon, during the period 1981 to 1984, suggests that the position of the warmer areas in the Bay of Bengal in May is an indicator of the subsequent summer rainfall over India. The statistical method adopted for the long range forcasting of the Indian summer monsoon gives very little consideration to the cause- effect relationships. None of the oceanic parameters is considered for this prediction. The storage and release of the thermal energy in the upper layers of the ocean is one of such parameters. For the lack of this information, a related parameter, the sea surface temperature is considered for a discussion on its relationship to the summer monsoon rainfall over India