| Summary: | Latent heat flux (LHF) over the tropical Indian Ocean (25 N to 25 S: 35 degrees E to 120 degrees E) for ten years from 1988 were computed using bulk parameterization method by making use of both monthly and weekly values of Sea Surface Temperature (Reynolds), Sea Surface Wind Speed and Integrated water vapor (from SSMI sensor onboard DMSP satellite series), mean sea level pressure (from NCEP/NCAR reanalysis data). Evaporation zones are identified over the western tropical Indian Ocean where the southwest monsoon wind forcing is active. Weekly and monthly rainfall data over the 35 meteorological subdivisions identified by the Indian Meteorological Department were used to study the relationship between LHF over the ocean and Indian summer monsoon rainfall. Rainfall represented by both coastal and central sections accounts for 70-80% of the rainfall from all 35 subdivisions. High annual rainfall years (1988,1993-95,1997) matches very well with the warm phase of ENSO. Relatively better correlation exists between the LHF (over Arabian Sea and Southern Ocean) and rainfall when there is a time lag of 4 weeks. Trends of LHF anomaly over the southern ocean for the ten year period matches very well with the rainfall anomaly over the Indian peninsula in spite of the fact that the trend closely follows the warm phase of ENSO. High rainfall anomaly in the southern sector of the Indian peninsula in 1988-89 in July provides evidence of strong moisture transport due to the shifting of the axis of LLJ which normally associated with break monsoon condition. Similar condition prevails over the northern sector of the peninsula in 1997 and the absence of rainfall in the south is an indication of a single core structure of LLJ during an active monsoon condition. The winter evaporation and the subsequent rainfall over the Indian peninsula exhibits strong association with the cold phase of ENSO.
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