Rainfall Statistics Over India

Rainfall is one of the most important parameters in climatology, agriculture, weather modification and weather monitoring. Moreover, it is of immense interest in communication and link designing as above 10 GHz it attenuates the signal giving rise to interruption in wave propagation. In addition to this rain gives rise to cross polarization effect in communication systems where frequency reuse technique in used in order to increase channel capacity. Hence study of rainfall, the attenuation and cross polarization effect needs careful study. Attenuation prediction methods like ITU-R needs rainfall rates at less integration time. The Meteorological Departments, however, supply rainfall data at hourly interval. Hence a conversion formula from hourly to less integration time, say 1- minute or 15 minutes is needed. In this paper conversion formulae have been derived between hourly and 15 minutes rainfall rate over few stations in India. The rainfall data have been collected from India Meteorological Department, Pune. Regression coefficients have been derived between hourly and 15-minutes rainfall rate data.