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The economy of the Indian subcontinent primarily depends on the two monsoons - the southwest and the northeast. The southeast monsoon occurs in June-September bringing rainfall throughout India. The northeast monsoon brings rainfall to the southern peninsula, from October-December. The two monsoons, especially the northeast one,demand very careful study due to devastating impacts of cyclones causing loss of life and property. The authors wish to investigate the two monsoons over a few locations in India, namely Bangalore, Bhubaneswar, Kolkata, Gadanki, Chennai, Machilipatnam, Kakdwip, Karaikal, Mangalore, Mumbai, Panjim, Puri, Trivandrum, and Vishakhapatnam, in the context of the dominance of convective and stratiform rain over surface rainfall. They have analyzed the frequency of occurrence of convective/stratiform rain, and the percentage contribution of these categories to surface rainfall. The authors use the cloud liquid water (CLW) and latent heat (LH) from the surface up to 18 km to investigate the occurrence of the peak cloud liquid water level (HPCL) and the levels of the multiple evolution latent heat (MLHevol). TheCLW and LH are obtained from the data product 2A12 of the Tropical Microwave Imager (TMI) aboard the Tropical Rainfall Measuring Mission (TRMM) satellite. The selected parameters (CLW and LH) are used to estimate contributions of convective and stratiform clouds to surface rainfall. The study analyzes the above-mentioned data during 1999-2008. The paper describes the salient features of the southwest and northeast monsoon in the light of convective/stratiform dominance of surface rainfall and the occurrence of HPCL at different levels in the atmosphere. The paper also reviews a few observable climatological aspects, viz. occurrence of cyclones and floods in the two monsoons.
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