Summer monsoon contributes approximately 80% of annual rainfall of India: Study

Researchers from the Indian Institutes of Technology (IIT) of Madras and Bombay have discovered that summer monsoon that falls between June and September, contributes approximately 80% of annual total rainfall of the country. This rainfall plays a decisive role on the country’s agricultural output as per their findings of the study variations in Indian summer monsoon rainfall for past century.

Using recorded rainfall data and simulation studies, the research team has gained insights critical not only for understanding geographic variations in seasonal rainfall in India, but also for framing long-term water management policies of the country. Their work has been published in the reputed peer-reviewed journal PLOS.The research team include Subimal Ghosh and Subhankar Karmakar from IIT Bombay, K.S. Kasiviswanathan, K.P. Sudhir and Sachin Gunthe from IIT Madras along with their research students.

This research is supported by the Max Planck Partner Group at IIT Madras, Department of Science and Technology, Government of India, and Ministry of Earth Sciences.


About 60% of Indian agriculture depends upon monsoon rain for irrigation, which in turn decides the economy as agriculture accounts for 18% of India's gross domestic product.

Recent observations, both at the meteorological level and from local perceptions, that monsoon has grown more unpredictable than before, with events such as the floods in Kerala and the ongoing zero-water situation in the adjoining state of Tamil Nadu becoming recurrent.